“...all the past is but a beginning of a beginning, and that all that is and has been is but the twilight of dawn.”

— H.G. Wells
1902

Universe Today

Syndicate content Universe Today
Space and astronomy news
Updated: 4 hours 34 min ago

Astronomers Map the Shape of a Black Hole's Corona for the First Time

Thu, 11/14/2024 - 11:24am

If you were lucky enough to observe a total eclipse, you are certain to remember the halo of brilliant light around the Moon during totality. It’s known as the corona, and it is the diffuse outer atmosphere of the Sun. Although it is so thin we’d consider it a vacuum on Earth, it has a temperature of millions of degrees, which is why it’s visible during a total eclipse. According to our understanding of black hole dynamics black holes should also have a corona. And like the Sun’s corona, it is usually difficult to observe. Now a study in The Astrophysical Journal has made observations of this elusive region.

For an active black hole, it’s generally thought that there is a donut-shaped torus of gas and dust surrounding the black hole, in which there is an accretion disk of heated material aligned along the rotational plane of the black hole. Streaming from the polar regions of the black hole are jets of ionized gas speeding away at nearly the speed of light. This model would explain the various types of active galactic nuclei (AGNs) we observe, since the orientation of the black hole relative to us changes the appearance of the AGN.

According to the model, the innermost region of the accretion disk should be a superheated region at near vacuum density, which streams into the black hole. It is a corona like the Sun’s, but instead of millions of degrees, it has a temperature of billions of degrees. But because it’s so diffuse, its light is overwhelmed by the light of the accretion disk.

Diagram of the polarization behavior of obscured black holes. Credit: Saade, et al

In this new study, the team used a trick similar to observing the Sun’s corona during a total eclipse. The orientation of a black hole relative to us means that for some black holes the torus of gas and dust obscures our view of the accretion disk region, while for other black holes we can see the disk directly. These are known as obscured and unobscured black holes. The obscured black holes are similar to an eclipsed Sun, since the light of the accretion disk is blocked from view. Unfortunately, so is the black hole’s corona. But the corona is so hot that it emits extremely high-energy X-rays. These X-rays can scatter off material in the torus and reflect into our line of site.

Using data from NASA’s Imaging X-ray Polarimetry Explorer (IPXE), the team gathered data on a dozen obscured black holes, including Cygnus X-1 and X-3 in the Milky Way, and LMG X-1 and X-3 in the Large Magellanic Cloud. They were not only able to observe scattered X-rays from the coronas of these black holes, they were also able to detect a pattern among them. Based on the data, the corona surrounds the black hole in a disk similar to the accretion disk, rather than surrounding the black hole in a sphere similar to the Sun’s corona.

Research such as this will help astronomers refine our models of black holes. It will also help us better understand how black holes consume matter and power the AGNs we observe in distant galaxies.

Reference: Saade, M. Lynne, et al. “A Comparison of the X-Ray Polarimetric Properties of Stellar and Supermassive Black Holes.” The Astrophysical Journal 974.1 (2024): 101.

The post Astronomers Map the Shape of a Black Hole's Corona for the First Time appeared first on Universe Today.

Categories: Astronomy

Yes, Virginia, The Universe is Still Making Galaxies

Thu, 11/14/2024 - 9:21am

Despite the fact that our universe is old, cold, and well past its prime, it’s not done making new galaxies yet.

Galaxy formation first got started when our universe was only a few hundred million years old. In those dark ages the first stars gathered enough material to trigger nuclear fusion and ignite. Slowly over time those clumps of stars found each other and began to build the first young protogalaxies. 

Over time those protogalaxies accumulated more material and merged together to quickly grow to become the massive galaxies that sprinkle throughout the universe today.

But galaxies are more than clumps of stars and gas. They are also deep wells of dark matter, which is the invisible substance that makes up the most of the mass of every object in the universe. To make a galaxy you really start with an accumulation of dark matter. That forms the gravitational bedrock for normal matter to gather onto and start forming stars.

The accumulation of dark matter really only happened in the very early universe, and long ago shut off. But those concentrations of dark matter remain today. Evidence from simulations and observations tells us that normal matter is still finding those pockets and triggering fresh rounds of star formation. That means while the seeds of galaxies were only laid down once, new accumulations of matter are still lighting up in the present day cosmos.

It is true that we are well past the peak of star formation and the heyday of galaxy assembly. That epoch came and went over 10 billion years ago. And far into the future our universe will expand so much that this process will slow down and eventually stop. But the universe isn’t done yet. For now, we can still enjoy a universe full of galaxies and knowing that new ones are still coming on the scene.

The post Yes, Virginia, The Universe is Still Making Galaxies appeared first on Universe Today.

Categories: Astronomy

Our Breathtaking Cosmos: New Zealand Astrophotography Winners Announced

Thu, 11/14/2024 - 9:06am

The New Zealand Astrophotography Competition showcases and recognizes some of the most stunning images of the southern hemisphere’s night sky. This year, photographers from across New Zealand have captured some incredibly breathtaking skyscapes such as amazing auroras, stunning images of our Solar System, and deep-sky marvels.

Universe Today was proud to be part of this year’s competition, as our own Fraser Cain was one of the judges.

The overall winner in the competition is a gorgeous view of the Aurora Australis, above, by photographer Tom Rae. Rae said he captured this image during the “once in a lifetime” geomagnetic storm in May of 2024, showing the Milky Way arching over the dramatic landscape of Aoraki Mount Cook National Park. This image also won the “Aurora” category.

The other categories in the competition include Deep Sky, Solar System, Dark-Sky Places, Timelapse, and new this year are Smartphone Images and a People’s Choice Award, chosen by the public.

There’s also a Nightscape category, and the winner –again — for this category is Tom Rae, showing the bowed Milky Way over a sharp ridge in Aoraki Mount Cook National Park.

“The Ridge” by Tom Rae, winner of the Artistic/Nightscape category of the 2024 New Zealand Astrophotography Competition. Credit and copyright: Tom Rae.

“This image is one of my biggest astrophotography accomplishments to date,” Rae explained on NZ Astrophotography Competition website, “and the largest panorama I’ve ever captured, with the full resolution image containing over a billion pixels from 62 images stitched together.”

Deep Sky “First Amateur Detection of Light Echoes from 19th-Century Great Eruption of Eta Carinae” by Rolf Wahl Olsen in the Deep Sky category of the 2024 New Zealand Astrophotography Competition. Credit and copyright: Rolf Wahl Olsen.

NZ astrophotographer Rolf Wahl Olsen is no stranger to Universe Today readers, as we’ve featured several of his photos for years. Olsen outdid himself with this deep sky photo of Eta Carinae.

“This is the first amateur image of light echoes from the 19th-century Great Eruption of Eta Carinae,” Olsen explained. “These light echoes have been detected by the Hubble Space Telescope and from large observatories such as the CTIO 4m telescope, but this is the first time that amateur images reveal these transient features.

Olson said his other first amateur detection of light echoes from supernova SN1987a inspired an attempt to try looking for the fainter echoes near Eta Carinae. You can read more about this effort on the NZ Astrophotography website and also at Olsen’s website.

Solar System “Solar Fury” by Navaneeth Unnikrishnan won the Solar System Category of the 2024 New Zealand Astrophotgraphy Competition. Credit and copyright: Navaneeth Unnikrishnan.

Navaneeth Unnikrishnan captured this stunning view of the full disk of the Sun. Using an H-alpha filter reveals the Sun’s dynamic surface and massive prominences. “A reminder of the incredible power and beauty just beyond our skies,” said Unnikrishnan.

Dark Sky “Endurance” by Abby Keith won the Dark Sky Places category of the 2024 New Zealand Astrophotgraphy Competition. Credit and copyright: Abby Keith.

Abby Keith captured this stunning dark sky photo while on a five-day hike in New Zealand’s in Fiordland National Park. The view shows Lake Mackenzie, a sub-alpine lake on the Routeburn Track, which is one of New Zealand’s Great Walks.  

This panoramic image consists of 16 images for the foreground and 38 images for the sky.

“This image is the hardest one I’ve had to work for,” Keith explained. Carrying a 20-plus kg pack was worth it, however, as there were perfect conditions to capture this view.

Smartphone “Lake Aviemore aurora” by Ian Griffin won the Smartphone category in the 2024 New Zealand Astrophotgraphy Competition. Credit and copyright: Iam Griffin.

This image was was also taken during the famous geomagnetic storm of May 12, 2024. Griffin called it “one of the most epic auroral storms I have ever seen. As my main digital cameras snapped away, I decided to see what my Iphone could do; I was blown away by the results!”

So are we! For more great astrophotos, check out Griffin’s website.

People’s Choice “Father and Son Magic” by Grant Birley won the People’s Choice Award in the 2024 New Zealand Astrophotgraphy Competition. Credit and copyright: Grant Birley.

New this year for this competition is the People’s Choice Award, where after short-list winners were announced, online voting was opened for the public to choose their favorite images. This beautiful and heartfelt image is definitely worthy of being a favorite. You can see more of Birley’s images on Instagram.

Timelapse

This breathtaking timelapse shows mountains rotating against the backdrop of the stars, instead of the usual view of the stars moving. This work was submitted by Last Quarter Photography on YouTube.

You can see all the winners, runners-up and highly commended images and videos at the NZ Astrophotography Competition website.

New Zealand Astrophotography Competition This is New Zealand’s leading annual astrophotography competition and it is run jointly by the Royal Astronomy Society of New Zealand (RASNZ) and the Auckland Astronomical Society. Along with Fraser Cain, the other judges this year were Judy Schmidt  — another name well-known to Universe Today readers for her imaging editing and cosmic creativity, and Dylan O’Donnell who operates the YouTube channel “Star Stuff.” 

Below is a video of all the short-list entries from this year’s competition.

The post Our Breathtaking Cosmos: New Zealand Astrophotography Winners Announced appeared first on Universe Today.

Categories: Astronomy

Why are Some Quasars So Lonely?

Thu, 11/14/2024 - 7:08am

At the centre of most galaxies are supermassive black holes. When they are ‘feeding’ they blast out jets of material with associated radiation that can outshine the rest of the galaxy. These are known as quasars and they are usually found in regions where huge quantities of gas exist. However, a recent study found a higher than expected number of quasars that are alone in the Universe. These loners are not surrounded by galaxies nor a supply of gas. The question therefore remains, how are they shining so brightly. 

A quasar or ‘quasi-stellar’ object as they are more formally known are among the most powerful and energetic objects in the Universe. They are usually powered by a supermassive black hole at the centre of a galaxy. Matter gets drawn toward the black hole by gravity and as it does, it spirals in forming an accretion disk. It is here that friction and gravitational forces heat material to extremely high temperatures emitting intense light and radiation that can outshine the light from all the stars in the galaxy put together. 

This is an artist’s illustration of a supermassive black hole that is inside the dust-shrouded core of a vigorously star-forming “starburst” galaxy. It will eventually become an extremely bright quasar once the dust is gone. New research shows that the object, discovered in a Hubble deep-sky survey, could be the evolutionary “missing link” between quasars and starburst galaxies. The dusty black hole dates back to only 750 million years after the big bang. NASA, ESA, N. Bartmann

The team of astronomers used NASA’s James Webb Space Telescope to explore 5 distant ancient quasars. They are thought to have formed between 600 and 700 million years after the Big Bang and are a billion times more massive than the Sun. They punt out so much energy that they are more than a trillion times brighter than our local star! 

The objects are 13 billion light years away but due to their extreme luminosity their light can be detected across the cosmos. The real surprise though is that they have been found in an unexpected variety of different environments. The ‘quasar fields’ as they are known include areas of space  crowded with galaxies as the models forecast. The others though seem to be isolated, drifting through space with only a few stray galaxies nearby. 

Using the James Webb Space Telescope between August 2022 and June 2023 multiple images were taken of each quasar field to produce a mosaic. The images were captured in multiple wavelengths and were stitched together provided a complete picture of the region of space around each quasar. Using this approach, the team could determine if the light was from a neighbouring galaxy or from the central quasar. 

Artist impression of the James Webb Space Telescope

The discovery flies in the face of quasar models that usually places them in host galaxies with a plentiful supply of gas and dust to keep them fed. Finding quasars floating in voids has left astronomers scratching their heads to understand and modify the theories. It is of course possible the host galaxies are just not visible, perhaps they are just shrouded by dust. 

When the quasars formed, the Universe would have been full of filaments of dark matter. The presence of the matter would attract gas and dust through gravitational interactions. It is from this material that the studied quasars would have formed. However the curiosity is that they would have had to grow at an incredible rate through accretion to achieve the luminosity seen just a few hundred years after the Big Bang. Further observations are needed of the quasar fields to try and identify the true nature of the area they exist within to truly understand their nature. 

Source : Astronomers detect ancient lonely quasars with murky origins

The post Why are Some Quasars So Lonely? appeared first on Universe Today.

Categories: Astronomy

Congressional Hearing Fuels Fresh Debate About UFOs

Wed, 11/13/2024 - 9:35pm

An 11-page document that’s attributed to a Pentagon whistleblower has provided new cases in the controversy over unidentified anomalous phenomena — also known as UAPs, unidentified flying objects or UFOs.

The document, released today in conjunction with a House subcommittee hearing on UAPs, lays out details about what’s said to be a special access program called Immaculate Constellation. It accuses officials in the federal government’s executive branch of a “criminal conspiracy” that has been managing issues surrounding UAPs and evidence for non-human intelligence “without congressional knowledge, oversight or authorization for some time, quite possibly decades.”

Over the past few years, the Department of Defense has become more open to discussing UAP reports publicly, while insisting that there have been no substantiated reports of alien visitations. During today’s hearing, lawmakers called on the Pentagon to be more transparent in its investigations.

“It is clear, from my experience and what I’ve seen, that there is something out there,” said Rep. Andy Ogles, R-Tenn. “The question is, is it ours? Is it someone else’s? Or is it otherworldly? … We must know, and anyone who prevents us from gaining access to that information, I would consider that criminality, because we have U.S. personnel who may very well be in harm’s way.”

The document claims that the Immaculate Constellation program has imagery and other data relating to encounters with a variety of anomalous objects. “From 1991 to 2022, the most common UAP shapes reported in this [U.S. government] dataset were spheres/orbs, discs/saucers, ovals/tic-tacs, triangles, boomerang/arrowhead, and irregular/organic,” it said. The irregular objects were described as having a “floating brain” or “jellyfish” appearance.

Michael Shellenberger, an author and journalist who received the document from the purported whistleblower, said he verified the source’s credentials and assured lawmakers that the document was authentic. He also said he’s continuing to gather reports from other sources.

“Since my reporting on this Immaculate Constellation last month, another source came forward,” Shellenberger said. “He told me that they saw a roughly 13-minute-long, high-definition, full-color video of a white orb UAP coming out of the ocean approximately 20 miles off the coast of Kuwait. It was filmed from a helicopter. Then halfway through the video, the person said, the orb is joined by another orb that briefly comes into the frame from the left before rapidly moving again out of the frame.”

Shellenberger said there may be “hundreds, maybe thousands” of UAP reports in the Immaculate Constellation database.

Mick West, a retired software engineer who specializes in analyzing UAP reports, was generally skeptical of the claims made during the hearing, which was conducted jointly by two subcommittees under the aegis of the House Oversight Committee. Nevertheless, West was intrigued by the purported whistleblower report — and said the Pentagon’s All-Domain Anomaly Resolution Office, or AARO, should follow up.

“The UFO document discussed in congressional testimony today contains descriptions of some interesting-sounding videos,” West said in a posting to the X social-media platform. “If these exist, I urge @DoD_AARO to make as many of these videos public as possible and share their analysis so we can get some clarity ASAP.”

In addition to Shellenberger, the witnesses at today’s hearing included retired Navy Rear Adm. Tim Gallaudet, who served as the acting administrator of the National Oceanic and Atmospheric Administration during the Trump administration; Luis Elizondo, a former intelligence official who is now an advocate for UAP disclosure; and Mike Gold, a former NASA associate administrator who was a member of NASA’s independent UAP study panel and is now chief growth officer at Redwire.

Witnesses at the UAP hearing included, from left, Tim Gallaudet, Luis Elizondo, Michael Shellenberger and Mike Gold. (Credit: House Oversight Committee via YouTube)

In advance of the hearing, Gallaudet came in for some strong criticism from Sean Kirkpatrick, who was in charge of AARO in 2022-2023 and is now chief technology officer for defense and intelligence programs at Oak Ridge National Laboratory in Tennessee. “Mr. Gallaudet is clearly still bitter that I didn’t hire him into AARO when he came looking for a job,” Kirkpatrick said in a statement distributed on X. “His predisposed tendencies for conspiracies without evidence made him unsuitable for a job that required objectivity and evidence-based reason.”

Kirkpatrick and others involved in the UAP debate have suggested that the likeliest explanations for anomalous aerial sighting have to do with advanced technologies that are being secretly employed by rival nations, including Russia and China. But questions about potential alien intrusions, secret crash retrievals and exotic technologies repeatedly came up during the hearing.

In response to such questions, Gallaudet said he believed some of the reports about UAPs could be attributed to non-human higher intelligence. Elizondo agreed. “Although much of my government work on the UAP subject still remains classified, excessive secrecy has led to grave misdeeds against loyal civil servants, military personnel and the public — all to hide the fact that we are not alone in the cosmos,” Elizondo said.

In contrast, Gold declined to weigh in definitively on questions about extraterrestrials. “I just don’t know,” he said. “I think we must be modest in our assumptions that we’re looking for intelligence that could be biological. It might not.”

For example, Gold said, some UAPs may be controlled by artificial intelligence. “We assume that all intelligence would be like us, and every time we look out in the universe, we are humbled relative to what we don’t know, in terms of the forms of intelligence and what it may take,” he said. “l probably can’t answer your question, but I think the ultimate answer is going to surprise us all.”

The witnesses and the lawmakers seemed unanimous in their support for greater transparency about UAP sightings. Congress is currently considering legislation that would strengthen current requirements for UAP disclosure and whistleblower protection.

Rep. Jared Moskowitz, D-Fla., hinted that more information may be forthcoming when Donald Trump returns to the White House. “This has been bipartisan, bicameral,” Moskowitz said. “As we get into a new administration, the president-elect has talked about opportunities to declassify information on UAPs, and I hope he lives up to that promise.”

The post Congressional Hearing Fuels Fresh Debate About UFOs appeared first on Universe Today.

Categories: Astronomy

New Study Examines How Extraterrestrial Civilizations Could Become “Stellarvores.”

Wed, 11/13/2024 - 8:20pm

One of the most challenging aspects of astrobiology and the Search for Extraterrestrial Intelligence (SETI) is anticipating what life and extraterrestrial civilizations will look like. Invariably, we have only one example of a planet that supports life (Earth) and one example of a technologically advanced civilization (humanity) upon which to base our theories. As for more advanced civilizations, which statistically seems more likely, scientists are limited to projections of our own development. However, these same projections offer constraints on what SETI researchers should search for and provide hints about our future development.

In a series of papers led by the Blue Marble Space Institute of Science (BMSIS), a team of researchers examines what Earth’s level of technological development (aka. “technosphere”) will look like in the future. In the most recent installment, they offer a reinterpretation of the Kardashev Scale, which suggests that civilizations expand to harness greater levels of energy (planet, host star, and galaxy). Instead, they suggest that the Kardashev Scale establishes upper limits on the amount of stellar energy a civilization can harness (a “luminosity limit”) and that civilizations might circumvent this by harnessing stellar mass directly.

As with the previous study in this series, the research was led by Jacob Haqq-Misra, the Senior Research Investigator at the Blue Marble Space Institute of Science. He was joined by George Profitiliotis, an Affiliate Research Scientist at the BMSIS and a Research Member of the Working Group on SETI and Law at the International Institute of Space Law (IISL), and Clement Vidalb, a researcher with the Center Leo Apostel (CLEO) at the Free University of Brussels. The paper “Projections of Earth’s Technosphere: Luminosity and Mass as Limits to Growth” is being reviewed for publication in Acta Astronautica.

Energy consumption estimated in three types of civilizations defined by the Kardashev Scale. Credit: Wikimedia Commons

The Kardashev Scale, named after Soviet-Russian astrophysicist and radio astronomer Nikolai Kardashev (1932 – 2019), was first proposed in his seminal paper, “Transmission of Information by Extraterrestrial Civilizations,” released in 1964. In it, Kardashev suggested what types of radio frequencies (and at what energies) scientists should search for to discern possible transmissions of an extraterrestrial civilization (ETC). In keeping with the idea that there may be civilizations billions of years older than humanity, he reasoned that these civilizations could harness levels of energy beyond human capabilities.

To characterize the level of an ETC’s development, Kardashev proposed a three-level scale based on the amount of energy they could harness. This included:

  • Type I – Planetary Civilizations: ETCs that have developed the means to harness and store all of their home planet’s energy, an estimated 4×1019 erg/sec.
  • Type II – Stellar Civilizations: ETCs that have evolved to the point where they can harvest all the energy emitted by their star – 4×10³³ erg/sec.
  • Type III – Galactic Civilizations: ETCs able to harness the energy of an entire galaxy 4×1044 erg/sec.

However, this scale reflected the assumption that civilizations and their energy needs will grow exponentially. This is in keeping with observations of humanity’s own “technosphere,” which refers to the human-made infrastructure, machinery, communications, and other indications of technological activity (aka “technosignatures”). Basically, it reflects our limited perspective when it comes to the kinds of behaviors advanced ETCs would exhibit. As Haqq-Misra told Universe Today via email:

“Earth is our only known example of a planet with technology, so the search for extraterrestrial civilizations must begin by thinking about how to search for analogs to Earth’s technosignatures today and possible technosignatures that could arise in Earth’s future. We should also try to stretch our minds to consider other, non-terrestrial, and more exotic possibilities, but even such imaginative possibilities will always either begin with (or contrast with) what we know is possible based on existing or known physics on Earth.”

Artist’s impression of a Dyson Sphere, a proposed alien megastructure that is the target of SETI surveys. Finding one of these qualifies in a “first contact” scenario. Credit: Breakthrough Listen/Danielle Futselaar

Traditional applications of the Kardashev Scale predict that growth will be exponential and have even considered how this could give rise to a civilization capable of utilizing the energy output of all stars in the Universe – a Type IV Cosmic Civilization! This application has motivated many searches for civilizations that have reached these scales of vast energy utilization, as indicated by megastructures (e.g., Dyson Spheres, Clarke Bands, etc.) and other advanced technospheres. For their study, Haqq-Misra and his colleagues took a different approach:

“Our study re-examines these assumptions by noting that civilizations can follow different trajectories for their expansion in space and their energy consumption. This involves tradeoffs between ‘exploration’ and ‘exploitation,’ and there are many possibilities for how a civilization might develop along these two dimensions. Some civilizations may prioritize exploration in physical distance without ever needing to expand their energy consumption to Kardashev Type I or Type II scales. Other civilizations may focus on exploitation and increase their energy use more locally. Some civilizations may attempt to find an optimal balance between exploration and exploitation.

“We also point out that the Kardashev scale is better considered as a theoretical limit to a civilization that utilizes stellar energy (luminosity). Rather than describing a trajectory that advanced civilizations will follow, the Kardashev scale is the uppermost limit for a civilization’s energy use, as it relates to expansion in physical distance, but a limit that may never actually be achieved due to thermodynamic efficiency limits. In other words, the Kardashev scale describes an upper-limit to the tradeoffs between exploration and exploitation, and a civilization that is dependent on stellar luminosity for its energy needs will always fall below the energetic and spatial limits described by the Kardashev scale.”

The scenario Haqq-Misra and his colleagues proposed presents some new and interesting possibilities for advanced civilizations. For example, suppose humanity ever reaches the limit of how much energy it can harness from our Sun. In that case, it may not choose to explore and settle other star systems (with the intent of harnessing the energy of more planets and more stars). Instead, they may turn to harvesting stellar mass itself.

Illustration of a white dwarf accreting mass by stripping its non-degenerate companion. Credit: ESO/Kornmesser

“Civilizations like this that consume stars, which we call ‘stellivores,’ would be able to expand in energy use beyond the luminosity limits of the Kardashev scale,” said Haqq-Misra. “We are not at this level as a civilization on Earth yet, but we can at least think about the possibility that harvesting mass and converting it into energy (as Einstein’s famous equation describes) provides a way for a civilization to reach energy use scales beyond those envisioned by the Kardashev scale.”

Like all projections on humanity’s future development, this study also has implications for future SETI surveys. This is in keeping with the assumption that ETCs in our galaxy would be older and more advanced than humanity at this point. It’s also consistent with the principle that “if we can conceive of it, someone else has probably done it already.” As Haqq-Misra explained, future SETI surveys should examine “accreting binaries,” closely orbiting binary stars with mass flowing from one star to another.

Maqq-Misra and his colleagues recommend that scientists observe accreting binaries to search for abnormal behavior, which could indicate technological activity:

“If some civilizations actually do evolve into stellivores, then some of these may look like such accreting binary star systems. We cannot claim that all, or even most, accreting binaries are actually technological civilizations, but we also cannot rule out the possibility that some of them could in fact be technological. It is worth keeping our minds open and actually searching for such evidence of advanced and exotic civilizations rather than ruling them out before we look.”

Further Reading: arXiv

The post New Study Examines How Extraterrestrial Civilizations Could Become “Stellarvores.” appeared first on Universe Today.

Categories: Astronomy

A Screw-Driven Robot Could Autonomously Mine Rocky Worlds

Wed, 11/13/2024 - 6:11pm

Navigating the harsh terrain of other rocky worlds has consistently been challenging. The Free Spirit campaign unfortunately failed in its goal to will the plucky Martian rover out of the morass it found itself in, despite two years of continual effort from some of the world’s best engineers. To combat this difficulty, other engineers have turned to alternative propulsion methods, and a team of researchers in the EU have done just that for their work on an autonomous mining robot. They decided to use an Archimedes screw as their primary propulsion method.

The team has already successfully tested various prototype iterations of their miniaturized mining robot. More recently have released a paper that detailed a mobility platform based on four individually controlled Archimedes screws that could be useful for more than just mining underground.

As with most engineering projects, they started with a computer model, which resulted in a CAD model that the team tested on different terrain. They weren’t the first ones to think of using an Archimedes screw as a driving mechanism. Existing research has pointed out that it is not the most efficient on some terrains. However, it can navigate almost all terrains to at least some degree.

The work described in the paper was part of the ROBOMINERS project, supported by the EU.
Credit – ROBOMINERS YouTube Channel

Kinematics models are critical to the development of any robot, and one with a relatively obscure propulsion system is no exception. Since Archimedes screws can be modeled from any observational angle, coordinating the operation of each of the four independent screws to align correctly to the desired direction required some complex modeling that was eventually hosted as part of the control algorithm on board a computer seated on top of the mobile platform.

Another part of the control algorithm required the robot to understand how it was orientated, and to do that, the team developed an integrated network of sensors. These ranged from time of flight positioning systems, which allowed the robot to gauge the distance to an object, to force sensors on the screws themselves that would ensure they wouldn’t over-torque and burn out their drive motors.

Once the sensors were selected and the preliminary control code was written, it was time to put it to a real environmental test. The team built a physical prototype, partly out of 3D-printed parts, and set about moving it about on various surfaces. The drive system worked well on snow, sand, frozen ground, and mud. However, it was mainly used to traverse level surfaces rather than the more complicated slopes that it might encounter in some environments, such as Mars. 

Fraser discusses how we might use robots to explore the Moon.

That is not to say the system cannot adapt to slopes – just that there is more work to be done. ROBOMINERS, the EU project focused on building an autonomous mining robot, is looking to complete its final prototype soon, and the results of the drive platform testing shown in this latest paper will help contribute to that. Someday, it might contribute to a similar robot on the moon or Mars.

Learn More:
Gkliva et al – A Multi-Terrain Robot Prototype With Archimedean Screw Actuators: Design, Realization, Modeling, and Control
UT – NASA Tests a Robotic Snake That Could Explore Other Worlds
UT – Snake Rovers Might be the Best Way to Explore the Surface and Tunnels on Mars
UT – NASA Redoubling Efforts to Contact Spirit

Lead Image:
Prototype of the screw-driven robot on leafy ground.
Credit – Gkliva et al.

The post A Screw-Driven Robot Could Autonomously Mine Rocky Worlds appeared first on Universe Today.

Categories: Astronomy

How Life Could Live Under the Ice on Mars

Wed, 11/13/2024 - 5:58pm

Mars has been a fascination to us for centuries. Early observations falsely gave impressions of an intelligent civilisation but early visiting probes revealed a stark, desolate world. Underneath the surface is a few metres of water ice and a recent study by NASA suggests sunlight could reach the layer. If it does, it may allow photosynthesis in the meltwater. On Earth this actually happened and biologists have found similar pools teeming with life. 

The exploration of Mars by space probes began in the 1960’s. It began with the Soviet Union Mars 1 and NASA’s Mariner mission and was soon followed by the well known Viking landers in 1976. They were the first missions to test surface material for signs of life. The Mars Pathfinder mission took along the Sojourner rover and was followed by Spirit and Opportunity rovers after the turn of the century. Curiosity rover was among the latest of the visitors along with Perseverance and China’s Tianwen-1. The focus of later missions has been the hunt for water and analysis of the climate and geology of the planet. This was not only to understand the conditions as the planet evolved but to pave the way for human exploration. 

The Viking 1 lander was the first to capture a real selfie. This is a mosaic of high-resolution images of Viking 1 at Chryse Planitia. Image Credit: NASA/JPL.

To date, there has been no evidence of life on Mars. The question has intrigued us for decades though. Of all the planets in the Solar System, Mars is the most likely place to have once harboured primitive life, chiefly due to the discovery of liquid water in the distant past. Evidence of ancient dried river beds has been found across the planet with mineral deposits indicating that Mars was once warmer, wetter and potentially far more habitable. Even organic molecules have been discovered by the Curiosity and Perseverance rovers but researchers continue to hunt for evidence (past or present) of microbial life. 

Mars, Credit NASA

A team of researchers from NASA have published a paper articulating their use of computer modelling to help the search. They have shown that sunlight can shine through the Martian water ice, perhaps even enough for photosynthesis to occur in shallow pools of meltwater. 

There are two types of ice on Mars, frozen water and frozen carbon dioxide. The study explored water ice which had mostly formed as snow had fallen on the surface during a Martian ice age millions of years ago. The team believe that the key to the study are the dust particles that obscure light reaching the deeper layers of ice. They suggest that sunlight will warm the dark dust more than surrounding ice and then cause ice to warm and melt. Some scientists believe that ice at the surface cannot melt due to the thin dry atmosphere causing it to turn straight to a gas. This won’t apply to the ice deeper in the surface layer. 

Almost pure water ice is seen in the ejecta surrounding this impact crater (8 meters in diameter), which formed in 2008. The only reason we can see ice at the surface here is because this crater is so young. As time passes, the ice will all sublimate and no longer be present at the surface. Image Credit: High Resolution Imaging Science Experiment camera, NASA/JPL-Caltech/University of Arizona.

Such a process has been observed on Earth where dust heats ice, melts and allows the dust to sink. Over time, the dust particles will stop sinking through the ice but still generate enough heat to melt the ice and create tiny voids. It is here that thriving ecosystems have been found hosting simple forms of life. 

The paper published in Nature Communications Earth & Environment, suggests the dusty ice can produce enough light at depths up to 3 metres to allow photosynthesis to occur. The subsurface pools of meltwater are protected from evaporating by the ice above. It also provides some protection from radiation too providing a possibly habitable environment for simple forms of life. The authors suggest the areas would likely form in the Martian tropics between 30 and 60 degrees latitude in both hemispheres. 

Source : Could Life Exist Below Mars Ice? NASA Study Proposes Possibilities

The post How Life Could Live Under the Ice on Mars appeared first on Universe Today.

Categories: Astronomy

NASA’s JPL Lays Off Another 325 People

Wed, 11/13/2024 - 4:00pm

NASA’s Jet Propulsion Lab has announced a second round of layoffs for 2024, this time laying off 325 people – about 5% of its workforce. The announcement was made on Nov. 12 in a memo sent to employees, which notes the layoffs could have been even larger. The last cut was made this past February, when 530 employees were let go. Part of the issues which forced the layoffs comes from the the possible cancelation of the Mars Sample Return mission. With the October 2024 launch of Europa Clipper, JPL doesn’t have a flagship mission in the pipeline right now.

As with the layoffs in February, the cuts have nothing to do with the individual performance; it’s all budget-related and an attempt to balance the books. NASA Headquarters passed on funding constraints in the current budget to JPL, and while JPL has tried to manage them, the results are the two rounds of difficult layoffs.  

“This is a message I had hoped not to have to write,” JPL Director Laurie Leshin said in the memo sent to all staff members. “Despite this being incredibly difficult for our community, this number [of layoffs] is lower than projected a few months ago thanks in part to the hard work of so many people across JPL.”

Dr. Laurie Leshin has been the director of the Jet Propulsion Laboratory since May 2022. Credit: JPL.

Leshin said the lab’s leadership has had to deal with “continued funding challenges” and an uncertain future as NASA has been juggling and reconsidering its priorities for deep space exploration. She noted that the reduction was spread across nearly all areas of JPL, including technical, project, business, and support areas to meet the available funding for Fiscal Year 2025. Leshin said that the outcome of the presidential election last week did not have any bearing on the layoffs.

“We have taken seriously the need to re-size our workforce, whether direct-funded (project) or funded on overhead (burden). With lower budgets and based on the forecasted work ahead, we had to tighten our belts across the board, and you will see that reflected in the layoff impacts,” Leshin wrote.

All employees were told to work from home today (Nov. 13) and everyone would receive an email whether their position was being eliminated or not. Leshin said JPL would offer “personalized support to our laid-off colleagues who are part of the workforce reduction, including offering dedicated time to discuss their benefits, and several other forms of assistance.”

Artist’s concept of a Europa Clipper mission. Credit: NASA/JPL

This second round of layoffs were not a surprise. During a recent town hall with employees, Leshin discussed the continued funding challenges and projections of what the potential impact on the JPL workforce could look like. She indicated her team had been working through multiple workforce scenarios to address the changes in funding, with the goal of minimizing adverse effects on JPL’s capabilities and workers. But despite their efforts, the conclusion was that this additional workforce reduction was inevitable.

After the layoffs today, JPL will be left with about 5,500 regular employees.

“These are painful but necessary adjustments that will enable us to adhere to our budget while continuing our important work for NASA and our nation,” JPL said in a statement.

On social media, JPL employees called the news “devastating,” and “awful.” Another said, “Can’t imagine the stress this will produce.”

But Leshin also said she believed this would be the last workforce reduction needed for the foreseeable future and that staffing levels at this point are now “stable and supportable.”

“While we can never be 100 percent certain of the future budget, we will be well positioned for the work ahead,” Leshin wrote. “This may not help much in this difficult moment, but I do want to be crystal clear with my thoughts and perspective. If we hold strong together, we will come through this, just as we have done during other turbulent times in JPL’s nearly 90-year history.”

Dare Mighty Things The “Dare Mighty Things” sign at JPL. Image by Nancy Atkinson.

JPL has a long and storied history — “Dare Mighty Things” is the Lab’s motto — with the Lab’s origins dating back to the 1930s, when Caltech professor Theodore von Kármán oversaw pioneering work in rocket propulsion. In the 1960s, JPL began to develop robotic spacecraft to explore other worlds, beginning with the Ranger and Surveyor missions to the Moon, quickly followed by Mariner missions to Mercury, Venus and Mars. Now, missions and instruments built or managed by JPL have visited every planet in our Solar System as well as studying the Sun. The iconic Voyager missions have now entered interstellar space.

Despite the difficult layoffs, Leshin was hopeful for what’s to come for JPL.

“We are an incredibly strong organization—our dazzling history, current achievements, and relentless commitment to exploration and discovery position us well for the future,” she wrote.

The post NASA’s JPL Lays Off Another 325 People appeared first on Universe Today.

Categories: Astronomy

Lessons From Ancient Earth’s Atmosphere: From Hostile to Hospitable

Wed, 11/13/2024 - 2:12pm

Will we ever understand how life got started on Earth? We’ve learned much about Earth’s long, multi-billion-year history, but a detailed understanding of how the planet’s atmospheric chemistry evolved still eludes us. At one time, Earth was atmospherically hostile, and its transition from that state to a planet teeming with life followed a complex path.

What made Earth so special? Research shows that while Earth is completely different from its neighbouring planets now, in the past, it shared many atmospheric characteristics with modern-day Venus and Mars. How did Earth turn out so different?

A better understanding of Earth’s atmospheric journey can help us understand some of the distant exoplanets we’ve detected. In the near future, new telescopes will be revealing more details of exoplanet atmospheres. Many puzzles await, and some of the solutions to understanding them could be found on ancient Earth.

Ancient Earth had a reducing atmosphere, which means that there was a lack of free oxygen. The atmosphere contained reducing gases like hydrogen and methane. These gases quickly react with oxygen and remove it from the atmosphere. Some of those same molecules also react with UV light, and the chemical reactions produce organic molecules.

While that’s a general outline of some aspects of ancient Earth’s atmosphere, there’s a lot of detail that needs to be constrained before a clearer picture emerges of Earth’s transformation.

Researchers at Tohoku University, the University of Tokyo, and Hokkaido University have developed a new model of atmospheric chemical reactions that sheds light on how Earth’s atmosphere evolved and how the first life may have arisen.

The research is “Self-Shielding Enhanced Organics Synthesis in an Early Reduced Earth’s Atmosphere.” It’s published in the journal Astrobiology, and Tatsuya Yoshida from Tohoku University is the lead author.

Before life could appear, Earth needed a good supply of important prebiotic molecules like formaldehyde (H2CO) and poisonous hydrogen cyanide (HCN). These molecules are critical because they can undergo a wide variety of reactions to produce the more complex molecules life requires. They produce amino acids, sugars, and nucleobases, which are the building blocks for DNA and RNA.

Research shows that a highly reduced atmosphere like ancient Earth’s is a candidate for producing these important prebiotic molecules, especially if it’s above a primordial ocean. Earth’s primordial ocean, or proto-ocean, was also much different from the modern ocean. Among other things, it was acidic because of volcanic gases. It was also hot.

Ancient Earth had hot, acidic oceans and a reducing atmosphere that lacked free oxygen. Image Credit: NASA/T.Pyle

“Ancient Earth was nothing like our current home,” explains co-author Shungo Koyama, also from Tohoku University. “It was a much more hostile place; rich in metallic iron with an atmosphere containing hydrogen and methane.”

The Sun’s UV radiation bombarded ancient Earth unimpeded by an ozone layer, driving chemical reactions in the ancient Earth’s atmosphere, oceans, and crust.

That much is understood. But what scientists desire is a better understanding of all of the details. “However, the branching ratio between organic matter formation and oxidation remains unknown despite its significance on the abiotic chemical evolution of early Earth,” the authors explain.

The researchers developed a photochemical model for a reduced Earth’s atmosphere primarily containing H2 and CH4. Their model is based on one that’s been successfully applied to Jupiter’s atmosphere, the atmospheres of ancient and modern Mars, and runaway greenhouse atmospheres. The model considers 342 separate chemical reactions and also includes atmospheric hydrogen escape and atmospheric mixing.

The young Sun emitted more intense UV radiation than the modern Sun. The UV broke water molecules down into hydrogen and oxygen radicals. Radicals have one unpaired electron, which makes them chemically reactive. Much of the hydrogen escaped to space, while the oxygen did not.

Illustration of what the Sun may have been like 4 billion years ago. Scientists think that overall, the young Sun was fainter than it is now. But it was also more active and had a higher level of magnetic activity. That activity made the Sun emit more UV than it does now. Credit: NASA’s Goddard Space Flight Center/Conceptual Image Lab

The oxygen radicals combined with methane led to the creation of organic molecules like HCN and H2CO.

Hydrocarbons, such as acetylene (C2H2) and methylacetylene (C3H4), were also present in the atmosphere. These chemicals absorbed some UV, shielding the lower atmosphere from photodissociation. “According to our results, UV absorptions by gaseous hydrocarbons such as C2H2 and C3H4 significantly suppress the H2O photolysis and following CH4 oxidation,” the authors explain. The atmospheric methane helped drive the production of organics.

That allowed organic molecules to accumulate into a prebiotic soup, which could’ve provided the building blocks for life.

“Accordingly, nearly half of initial CH4 possibly becomes converted to heavier organics along with deposition of prebiotically essential molecules such as HCN and H2CO on the surface of a primordial ocean for a geological timescale order of 10-100 Myr,” the authors write.

This diagram shows the evolution of Earth’s ancient atmosphere estimated by this study. Earth initially had a reducing atmosphere with lots of H2 and some CH4. Intense UV energy from the Sun split water into hydrogen and oxygen radicals, with much of the hydrogen escaping into space. CH4 that remains in the atmosphere is converted into organics. Earth loses its ancient CH4 and H2-rich atmosphere, the CH4 decomposes, and a layer of organics several hundred meters thick accumulates. Image Credit: Yoshida et al. 2024

As time went on and the reduced atmosphere evolved, H2CO and HCN were continuously synthesized and accumulated in the ocean. H2CO and HCN are considered to be critical in prebiotic chemistry. According to these results, Earth’s early atmosphere was a major source of these important prebiotic molecules. They didn’t need to come from meteorites or comets.

The authors calculate that a layer of organic several hundred meters thick may have covered the ocean. “The continuous supply of these prebiotically important molecules could potentially lead to the synthesis of amino acids, nucleobases, sugars, and their polymers,” the researchers write.

“There may have been an accumulation of organics that created what was like an enriched soup of important building blocks. That could have been the source from which living things first emerged on Earth,” said lead author Yoshida.

The model shows that Earth’s early atmosphere was eerily similar to modern-day Mars and Venus. However, Earth evolved into a completely different world. How?

This research doesn’t explain it all. But it does deepen our understanding of the evolutionary track Earth followed.

The question becomes, is Earth unique? Or is it a common path that exoplanets in other Solar Systems can follow?

The post Lessons From Ancient Earth’s Atmosphere: From Hostile to Hospitable appeared first on Universe Today.

Categories: Astronomy

Astronomers Defy the Zone of Avoidance to Find Hundreds of New Galaxies

Wed, 11/13/2024 - 10:23am

There is a region of the sky where astronomers fear to look. Filled with dark clouds of dust, it hides an unseen mass. A mass so large it is pulling the Milky Way and other galaxies toward it…

Okay, maybe that’s overdramatic, but it is true. The region is known as the Zone of Avoidance, and it happens to be in the general direction of the galactic center. Our view of the Universe isn’t as perfect as we’d like. The Sun is located within the galactic plane of the Milky Way, about 30,000 light-years from its center. So if we look to the north or south of the galactic plane, we get a pretty normal view of the cosmos. We can peer deep into the sky and see distant galaxies. But if we look toward the galactic center, we don’t have a clear view. Instead, we see a bunch of stars, gas, and dust. This is fine if you want to study stars, gas, and dust, but it means our view of the distant Universe is obscured in that direction. So if you want to make an unbiased view of the cosmos, you avoid that region, hence the term.

It’s also true that we’re being pulled in that direction. There happens to be a supercluster of galaxies that way, called the Great Attractor. We can map it out a bit by studying the relative motion of nearby galaxies, and we can observe X-rays from the supercluster, so we know it’s out there. But with all the gas and dust in the Zone of Avoidance, we can’t study it in the optical. One thing we know so far is that the Great Attractor actually consists of multiple clusters. The closest one is known as the Norma cluster, while a larger and more distant one is called the Vela supercluster. Still, there is much we don’t know about the region.

Fortunately, radio light can penetrate the dust of the Zone, so radio astronomers have tried to map the region. One downside is that radio telescopes often don’t have a large field of view, so it’s difficult to map the region. But a new work is making progress.

Observed galaxies within the Vela supercluster. Credit: Sambatriniaina H. A. Rajohnson, et al

The new study uses data from the MeerKAT array telescope in South Africa. MeerKAT is particularly sensitive to the radio emissions of neutral hydrogen, known as the HI or [21-centimeter line.](https://briankoberlein.com/blog/dark-line/) Since hydrogen is so abundant in the Universe, the distribution of hydrogen tells us the distribution of galaxies and clusters. The study mapped the region of the Zone in the direction of the Vela supercluster with enough resolution to distinguish individual pockets of neutral hydrogen, each surrounding a galaxy. In this way, the team was able to discover 719 galaxies within the Vela cluster. Less than a third of them had been known previously.

This was just the first detailed survey of the Vela supercluster by MeerKAT, and it shows the real power of this relatively new observatory. Future studies should give us an even better understanding of the zone astronomers so often avoid.

Reference: Sambatriniaina H. A. Rajohnson, et al. “Revealing hidden structures in the Zone of Avoidance — a blind MeerKAT HI Survey of the Vela Supercluster.arXiv preprint arXiv:2411.07084 (2024).

The post Astronomers Defy the Zone of Avoidance to Find Hundreds of New Galaxies appeared first on Universe Today.

Categories: Astronomy

An Otherworldly Cloud Over New Zealand

Tue, 11/12/2024 - 6:41pm

Filmmakers love New Zealand. Its landscapes evoke other worlds, which explains why so much of The Lord of the Rings was filmed there. The country has everything from long, subtropical sandy beaches to active volcanoes.

The country’s otherworldliness extends into its atmosphere, where a cloud nicknamed the “Taieri Pet” forms when conditions are right.

The Taieri Pet is a lenticular cloud, a stationary type of cloud that forms in certain circumstances. They form in the troposphere when the wind blows over an obstacle, typically a mountain range. There are three types: altocumulus standing lenticular (ACSL), stratocumulus standing lenticular (SCSL), and cirrocumulus standing lenticular (CCSL). Each type forms at a different altitude.

When the wind is forced to move up and over an obstacle, it creates a lower-pressure zone on the leeward side. As the wind moves, it creates standing waves. If conditions are right, these waves become visible when the moisture condenses.

The Taieri Pet forms over New Zealand’s Rock and Pillar Range in the Strath-Taieri region of Otago on New Zealand’s South Island.

The Otago region on New Zealand’s South Island is home to the Taieri Pet. Image Credit: Peetel, (Creative Commons Attribution-Share Alike 4.0 International.)

The cloud is a common feature near the town of Middlemarch. It’s mentioned in newspapers as far back as the 1890s. Locals sometimes took Taieri Pet’s appearance as a signal that a storm was coming.

This page is from the Otago Witness, Issue 2226, 29 October 1896. It describes the Taieri Pet as “our old prognosticator,” because it forms before a wind storm. Image Credit: No Known Copyright.

The Operational Land Image (OLI) on Landsat 8 captured this stunning image of the Taieri Pet in September. Landsat 8 follows a polar orbit that allows it to observe the entire surface of the Earth every 16 days.

This zoomed-in image shows the cloud and the surface in more detail. The image shows the Macraes Mine, New Zealand’s largest gold mine. Image Credit: NASA/Lauren Dauphin; USGS

The Landsat satellites have been monitoring Earth for over 50 years from their orbit 705 km above us. The images and data are widely used by scientists, but they’re also beautiful portraits of our extraordinary, once-in-a-solar-system planet.

Anybody can enjoy the Landsat galleries, found here.

The post An Otherworldly Cloud Over New Zealand appeared first on Universe Today.

Categories: Astronomy

Early Black Holes Fed 40x Faster than Should Be Possible

Tue, 11/12/2024 - 6:28pm

The theory goes that black holes accrete material, often from nearby stars. However the theory also suggests there is a limit to how big a black hole can grow due to accretion and certainly shouldn’t be as large as they are seen to be in the early Universe. Black holes it seems, are fighting back and don’t care about those limits! A recent study shows that supermassive black holes are growing at rates that defy the limits of current theory. Astronomers just need to figure out how they’re doing it! 

Black holes usually form from the collapse of a massive star. The origin of their larger cousins, the supermassive black holes found at the centre of most galaxies, remains a mystery. Theories suggest they grew over billions of years by consuming stars, gas and maybe even other black holes. Others suggest they formed from the primordial conditions of the early Universe or maybe from dense clusters of hot young early stars. The immense gravity from them plays a significant part in shaping stellar formation and the evolution of their host galaxy. If a supermassive black hole is actively accreting material, they are often seen as quasars, extremely luminous objects that are visible across million, even billions of light years. 

Illustration of a powerful black hole and its magnetic field. Credit: L. Calçada/ESO

A recent discovery by a team of astronomers revealed a low-mass supermassive black hole that was devouring material at an extreme rate. The black hole is at a distance that means we are seeing light as it was 1.5 billion years after the Big Bang. This means we can learn about the processes that govern these objects when the Universe was a lot younger. 

The black hole known as LID-568 was detected by a team of astronomers led by the International Gemini Observatory/NSF NOIRLab astronomer Hyewon Suh. It was detected in images from the James Webb Space Telescope following on from assessment of galaxies from the Chandra X-ray Observatory’s COSMOS legacy survey. The galaxies observed are bright X-ray sources but not visible in optical or near-infrared surveys. The team used JWST’s NIRSpec instrument that is capable of getting a spectrum off each individual pixel in its field of view. 

The Gemini North telescope on the summit of Mauna Kea (Gemini Observatory/AURA)

The study allowed the team to make the rather unexpected discovery of immense flows of gas out from the region around the centre of the black hole.  Suh and team could infer from this that a significant fraction of the growth of LID-568  may well have occurred in one single rapid accretion event. They calculated that it must be feeding on matter at a rate which is 40 times the Eddington limit. The limit relates to the maximum luminosity it can achieve acknowledging there is a balance between the outward force of radiation and the inward force of gravity. When the two forces balance, it is known as hydrostatic equilibrium. If an object exceeds the limit then an immense outward force will result in it losing mass. When the luminosity of LID-568 was calculated it was much higher then should be theoretically possible. 

The discovery provides an excellent opportunity for astronomers to study black holes in the early Universe and in particular those that challenge the Eddington limit theory. It would however suggest that the outflows of energy are acting to release energy that has built up during extreme accretion periods. Follow up observations are required. 

Source : NSF NOIRLab Astronomers Discover the Fastest-Feeding Black Hole in the Early Universe

The post Early Black Holes Fed 40x Faster than Should Be Possible appeared first on Universe Today.

Categories: Astronomy

A Spider Stellar Engine Could Move Binary Stars Halfway Across a Galaxy

Tue, 11/12/2024 - 5:33pm

Eventually, every stellar civilization will have to migrate to a different star. The habitable zone around all stars changes as they age. If long-lived technological civilizations are even plausible in our Universe, migration will be necessary, eventually.

Could Extraterrestrial Intelligences (ETIs) use stars themselves as stellar engines in their migrations?

In broad terms, a stellar engine uses a star to generate work. A simple example is solar panels, which use the Sun’s radiation to generate electricity that we use to perform work. But the scaled-up idea is to use the star to produce thrust. That thrust could be used to move the star itself. An ETI capable of doing that would be a Type II civilization on the Kardashev Scale.

To most of us, it seems like a wildly improbable idea. But who knows what’s out there? If an ETI can survive long enough, it may become a Type II civ.

The stellar engine idea dates back to science fiction author Olaf Stapledon. A couple of decades after Stapledon, astronomer Fritz Zwicky also discussed manipulating stars with advanced technology, even turning them into spacecraft. In the decades since, the idea has persisted, and other researchers have delved into it. In 1988, Leonid Shakdov developed the first detailed stellar engine model called the Shakdov Thruster.

In new research, Clement Vidal, from Vrije Universiteit in Brussels, Belgium, examines how an advanced civilization could use a binary star as a stellar engine. The paper is titled “The Spider Stellar Engine: a Fully Steerable Extraterrestrial Design?

“Since about half the stars in our galaxy are in binary systems where life might develop too, we introduce a model of a binary stellar engine,” Vidal writes. “We apply the model to candidate systems, spider pulsars, which are binary stars composed of one millisecond pulsar and a very low-mass companion star that is heavily irradiated by the pulsar wind.”

Vidal is concerned with stellar engine technosignatures. Research has focused on hypervelocity stars as potential stellar engine technosignatures because they’re easily observable. Other researchers have also proposed other stellar engine concepts, but according to Vidal, they’re “poorly linked to observable technosignatures. ”

Vidal’s main goal in this work is to determine what types of technosignatures a binary stellar engine would emit. He discusses what potential signatures might be emitted by acceleration, deceleration, steering, and maneuvers such as gravitational assists or captures. However, unlike some other researchers, he focuses on a specific type of binary system: spider pulsars, which are a subclass of binary millisecond pulsars.

Pulsars are what remains of some massive stars. At the end of their lives, some massive stars collapse to form neutron stars. When these neutron stars spin rapidly, they produce beams of radiation from their poles. If the radiation is aimed at Earth, then we can observe the pulses of energy. These pulses have exquisitely precise timing, and astronomers use them to determine cosmic distances.

A spider pulsar is a pulsar with a companion, usually a red dwarf, a brown dwarf, or even a planetary-mass object. They’re called spider pulsars because it’s as if the pulsar spins a web of powerful beams of radiation that strips away the companion’s mass, eventually destroying it.

Artist’s impression of a so-called “Black Widow” pulsar PSR B1957+20 (seen in the background) through the cloud of gas enveloping its brown dwarf star companion. Credit: Dr. Mark A. Garlick; Dunlap Institute for Astronomy & Astrophysics, University of Toronto

Vidal’s paper describes the payload as a pulsar with about 1.8 solar masses and the propellant as its low-mass companion star with between 0.01 and 0.7 solar masses.

In essence, the gravitationally bound binary system is the vehicle, and the smaller companion star is the propellant. The spider pulsar generates thrust by expelling propellant out of the gravitational system, and the propellant is the matter stripped from the companion.

The binary pair orbits a common center of gravity. The idea behind this binary stellar engine (BSE) is that as they orbit, the pulsar’s radiation strikes the companion or propellant star. A close binary is more effective because the closer the pulsar is to the propellant, the more thrust is generated. The assumption is that a Type II civilization would have the technology to moderate this thrust to serve their purposes by timing the radiation and heating the outer layers of the propellant star with X-ray or gamma radiation.

To decelerate, the BSE would produce active thrust in the opposite direction of travel. It could also use a passive magnetic sail deployed from the pulsar to transfer momentum to the interstellar medium.

The BSE steers by selectively evaporating the star during different orbital phases. “To choose a direction, it suffices to evaporate the companion star once per orbit, at a specific orbital phase, in order to create consistent thrust in one direction,” Vidal explains.

The top panels show the BSE in different configurations, with the top being the direction of travel. (a) The BSE is in acceleration mode. (b) the BSE is steering to the left. (c) the BSE is decelerating. (d) is a side view that shows changes in the orbital plane by asymmetric heating of the companion, which creates a lifting
force in relation to the orbital plane. The binary separation is not to scale. Image Credit: Vidal et al. 2024.

These various maneuvers and manipulations with the BSE would emit technosignatures. Have astronomers observed any candidate BSEs in the Milky Way? Possibly.

“Could our galaxy host a kind of fully steerable binary stellar engine that we proposed? This is a plausible hypothesis in the context of the stellivore hypothesis, which reinterprets some observed accreting binary stars as advanced civilizations feeding on stars,” Vidal writes.

A stellivore is a hypothesized type of civilization first proposed by Vidal that has the technology to consume its home star via accretion. They use the star’s energy to sustain their existence. Vidal writes that rather than consume the energy, they could use it to migrate to a more favourable location in the galaxy.

“For most of its time, a stellivore civilization would eat its home star via accretion. However, energy is never eternal, and instead of eating its star until the end and dying, a stellivore civilization would use its low-mass companion star as fuel not to be accreted but to be evaporated in order to create thrust and travel towards a nearby star,” Vidal explains.

This brings us to spider pulsars. Rather than accreting material, a spider pulsar appears to be evaporating its propellant companion.

There are two types of spider pulsars: Black Widows and Redblacks. The distinction is in the mass of the companion. In a black widow (BW), the companion is less than 0.1 stellar masses. In a redblack, the companion is between 0.1 and 0.7 stellar masses. Spider pulsars are different from other pulsar binaries because they evaporate their companions rather than accrete them. When pulsars accrete too much material, they can form black holes. Spider pulsars don’t tempt the same fate. Vidal calls these spider stellar engines (SSEs) rather than binary stellar engines (BSEs).

The panels in this figure show PSR J1959+2048, the original Black Widow pulsar. Left: the BW pulsar (in blue) is plotted in the RA-DEC plane, and its proper motion vector is displayed until it reaches a close encounter with a target star, in orange. Middle: a Chandra X-ray view of the BW pulsar, displaying a comet-like tail; the candidate target star is also visible in the bottom right (visualization with ESASky). Right: The composite image on the right shows the X-ray tail (in red/white) and a bow shock visible in the optical (green). Credit: X-ray: NASA/CXC/ASTRON/B. Stappers et al.; Optical: AAO/J.Bland-Hawthorn & H. Jones.

Previous researchers have studied the original BW, and Vidal writes, “… the 3D motion of the system appears to be nearly aligned with the spin axis of the MSP.” This fits in with the SSE interpretation because this perfect alignment is necessary to produce maximum thrust. A stellivore civilization would have a destination in mind, and Vidal says that he’s found a potential destination for the original Black Widow pulsar. He says that the pulsar will reach this target star in about 420 years while also acknowledging the uncertainty in this determination.

PSR J1959+2048, the original BW, also modulates itself, which could be interpreted as steering. However, it also displays other characteristics and moderation that call into question the ‘steering’ interpretation.

Ultimately, Vidal’s SSE may have a shorter duty cycle than other proposed stellar engines, limiting its usefulness. However, it has advantages in steering over others. “Transposing it on a smaller scale, it might also be an inspirational design for advanced propulsion solutions, or for planetary defence purposes such
as deflecting asteroids,” Vidal writes.

The idea may seem preposterous to some, but that’s incidental. Many ideas in history seemed preposterous until they weren’t.

Vidal isn’t claiming that we’re seeing the technosignatures of stellar engines. He’s arguing that it’s worth pursuing the idea of observing them. He sees these candidates and predictions of what their signals might look like as clues and as starting points for further investigation.

“Spider pulsars thus offer observable stellar engine technosignature candidates, with decades of data, active studies that discover, model and monitor these dazzling systems,” he concludes.

The post A Spider Stellar Engine Could Move Binary Stars Halfway Across a Galaxy appeared first on Universe Today.

Categories: Astronomy

Scaling Propellant Production on Mars is Hard

Tue, 11/12/2024 - 12:12pm

Putting humans on Mars has been one of NASA’s driving missions for years, but they are still in the early stages of deciding what exactly that mission architecture will look like. One major factor is where to get the propellant to send the astronauts back to Earth. Advocates of space exploration often suggest harvesting the necessary propellant from Mars itself – some materials can be used to create liquid oxygen and methane, two commonly used propellants. To support this effort, a group from NASA’s COMPASS team detailed several scenarios of the infrastructure and technologies it would take to make an in-situ resource utilization (ISRU) system that could provide enough propellant to get astronauts back to a Mars orbit where they could meet up with an Earth return vehicle. However, there are significant challenges to implementing such a system, and they must be addressed before the 8-9-year process of getting the system up and running can begin.

To understand these challenges, it’s first essential to understand some of the requirements the team was trying to meet. The goal was to provide 300 tons of liquid oxygen and liquid methane to a Mars Ascent and Landing Vehicle (MALV) being developed at other parts of NASA. That much propellant is necessary to get a crew of astronauts back into orbit, where they can be met by an orbiting Earth return vehicle.

Creating liquid oxygen and methane requires many ISRU systems, such as pumps, electrolyzers, dryers, scrubbers, and significant power systems, to run all these machines. Some raw materials, such as CO2, can be pulled from the Martian atmosphere. However, the system will also require 150 tons of water, which could be trucked in from Earth or harvested from Mars.

Fraser discusses how ISRU can provide resources to use for exploration.

Designing the overall system architecture is the first step in determining the best method for getting enough propellant to get the astronauts back off of Mars. A paper from the group compares five different approaches to solving that problem and details three of them, focusing on three different methods of getting water to use in the creation of liquid propellants on the surface of Mars.

Let’s first look at the two options for extracting water locally on Mars. One architecture uses a borehole drill to melt subsurface ice and pump it back to the surface, which can be used in electrolysis. The other architecture uses surface harvesting techniques, where soil with a high frozen water content can be sorted, and the water itself melted to provide sufficient stockpiles for creating propellant.

Drilling a borehole deep enough to access subsurface ice has never been done before. It does have some advantages over other water collection methods, including taking less time and requiring one less MALV delivery of equipment (i.e., making it lower cost). However, it does require more power plants and some specialized equipment to be developed. 

Fraser speculates on how a real Mars mission could play out.

Collecting water from surface regolith utilizes some technologies already being developed at NASA – including the RAZZOR surface mining system that could be used on the Moon or Mars. However, it requires as much time and as many launches as shipping water from Earth, with many possible unknown failure points in the architecture. 

By comparison, sending 150 tons of water directly from Earth, while it might be expensive in terms of launch costs, simplifies the overall architecture significantly. There would still technically be ISRU in this scenario, as the water would still be used to create propellant from local Martian resources. However, the added step of getting that water locally would be eliminated.

Even that is a more complicated process than the other two options the team considered, without as much detail in the paper as the actual ISRU setups. Mission designers could send either the methane or both the methane and oxygen from Earth directly, bypassing the need for any ISRU to happen. While these options require potentially more MALV landers, their overall risk is minimized, as the necessary chemicals would be available for use at any point the astronauts would need them. However, they would take longer to set up – especially the option of sending all of the propellants directly from Earth, which could take upwards of 10 years to get set up.

Fraser interviews Dr. Michael Hecht, an expert in ISRU on Mars.

Other challenges abound for utilizing Martian resources to create propellants – including limited locations where the necessary water may be found. This geographical restriction might not overlap with where astronauts might be needed to do exciting science, so the architects would have to prioritize either scientific discovery or derisking the ISRU equipment – they likely couldn’t do both.

So, all things considered, if the purpose is to send people to Mars and back safely, it seems like the best, most reliable option is to send the total amount of propellant from Earth. However, in the long run, if humanity plans to make a sustainable presence on Mars, we will need to utilize local resources. The paper from the COMPASS team clearly defines a few strategies that could do that, and someday, it will become the better option – just maybe not quite yet.

Learn More:
Oleson et al – Kiloton Class ISRU Systems for LO2/LCH4 Propellant Production on the Mars Surface
UT – A Single Robot Could Provide a Mission To Mars With Enough Water and Oxygen
UT – Resources on Mars Could Support Human Explorers
UT – Mars Explorers are Going to Need air, and Lots of it. Here’s a Technology That Might Help Them Breath Easy

Lead Image:
Architecture Design of the water from Earth delivery option.
Credit – Oleson et al. / NASA

The post Scaling Propellant Production on Mars is Hard appeared first on Universe Today.

Categories: Astronomy

Is an ‘Off-Year’ Leonid Outburst in the Cards For November?

Tue, 11/12/2024 - 11:44am

There are good reasons to keep an eye on the Leonid meteors this year.

It’s still one of the coolest things I ever saw. I was in the U.S. Air Force in the 90s, and November 1998 saw me deployed to the dark skies of Kuwait. That trip provided an unexpected treat, as the Leonid meteors hit dramatic storm levels on the morning of the 17th. Meteor came fast and furious towards local sunrise, often lighting up the desert floor like celestial photoflashes in the sky.

Once every 33 years or so, the ‘lion roars,’ as Leonid meteors seem to rain down from the Sickle asterism of the constellation Leo. And while the last outbreak was centered around the years surrounding 1999, there’s some interesting discussion about possible encounters with past Leonid streams in 2024.

The Leonids in 2024

To be sure, 2024 is otherwise slated to be an off year for the shower. The normal annual maximum for 2024 is expected to occur on Sunday, November 17th at around ~4:00 Universal Time (UT), with an expected Zenithal Hourly Rate (ZHR) of 15-20 meteors per hour seen under ideal conditions. This favors Europe in the early dawn hours.

The Leonid radiant, looking east at 2AM local. Credit: Stellarium. A Leonid Outburst in 2024?

But there are also a few other streams that may arrive earlier this week and are worth watching for. Jérémie Vaubaillon of the Paris Observatory IMCCE notes that Earth may encounter three older streams from periodic comet 55P/Tempel-Tuttle. The comet is the source of the Leonids. On a 33.8 year orbit, a meteor shower occurs when the Earth plows headlong into the stream of dust and debris laid down by the comet.

The three suspect trails are:

-A trail laid down in 1633 (the source of the 2001 meteor storm). Earth is near this trail on November 14th at 16:37 UT, favoring northwestern North America in the early morning hours.

-A dust trail from 1733, peaking on November 19/20th at 23:53 to 00:54 UT, favoring north/central Asia.

-And finally, an encounter with a string of older (more than a millennium old) streams on November 14th at 16:37 UT, (the same time as the 1633 stream). It is worth noting that the 1733 stream was the suspected source of the 1866 Leonid meteor storm.

A bright green Leonid from 2023. Credit: Frankie Lucena.

Watching this Thursday morning on the 14th could be a harbinger as to whether or not we’re in for a show. Unfortunately, the Moon is waxing gibbous and headed towards Full this week on November 15th, meaning that it with provide increasing illumination and cut down observed meteor rates.

The Leonids on past recent years have held steady at predicted rates of about or so 20 per hour. It’s worth noting that another encounter with the 1699 stream and possible outburst is predicted for next year, 2025.

Leonid TEFF (Total Effective observation time) rate versus meteors over the years. Credit: the International Meteor Organization (IMO). Meteor Shower… or Storm?

Meteor storms occur when the zenithal hourly rate tops 500 or more per hour. Keep in mind, a ZHR of a thousand or higher means that you’re seeing a meteor every few seconds. The October Draconids and the December Andromedids are also prone to great outbursts, but the Leonids are the most notorious and well-known. The 1966 shower seen over the U.S. southwest topped an amazing ZHR of up to 150,000 per hour (!)

A depiction of the 1833 outburst over Niagara Falls. Credit: Mechanic’s Magazine/Popular Domain. Observing and Imaging the Leonids

Early morning hours are best to see meteors, as you’re standing on the swath of the surface of the Earth that’s turned forward in to the stream. Pinpoint meteors will occur near the shower radiant, while long streaks will stand out out in stark profile about 45 to 90 degrees away on either side of the radiant. I like to aim my tripod-mounted DSLR at these regions, set the lens to the widest field of view possible, and simply let it run taking auto-exposures and see what turns up. An intervalometer is a great device to automate this process. This allows me to just sit back with a steaming hot cup of tea (a must for cold November mornings) and simply watch the show, as meteors slide by.

A Leonid pierces the night sky over southern Arizona. Credit: Eliot Herman.

Perhaps, we’ll simply have to wait for 2030s to see strong activity from the Leonids again. But do you really want to risk missing a surprise show? To quote hockey player Wayne Gretzky: “You miss 100% of the shots you don’t take.” The same holds true for missing versus catching meteor storms: you just have to show up and watch.

The post Is an ‘Off-Year’ Leonid Outburst in the Cards For November? appeared first on Universe Today.

Categories: Astronomy

Reaction Engines Goes Into Bankruptcy, Taking the Hypersonic SABRE Engine With it

Tue, 11/12/2024 - 6:33am

Rarely does something get developed which is a real game changer in space exploration. One example is the Skylon reusable single-stage-to-orbit spaceplane. Powered by the hypersonic SABRE engine it operates like a jet engine at low altitude and more like a conventional rocket at high altitude. Sadly, ‘Reaction Engines’ the company that designs the engines has filed for bankruptcy.

Launching rockets into space is an expensive business and it has often been a significant barrier in space exploration. This is largely because traditional rockets include a significant proportion of expendable elements. A typical launch into low Earth orbit for example can cost anything from tens to hundreds of millions of dollars due to those single use components. Movement has however been seen with reusable rocket technology like the Falcon 9 and Starship rockets which are refurbished and reused for multiple launches. This has helped to drive down the cost of a rocket launch but still about $2,000 per kilogram there is still much to do to drive down the cost of space exploration. 

A SpaceX Falcon 9 rocket sends the European Space Agency’s Hera spacecraft into space from its Florida launch pad. (Credit: SpaceX)

The idea for a fully reusable single-stage-to-orbit (SSTO) spaceplane is one such development and was the brainchild of Reaction Engines Limited. The Skylon spaceplane was designed to take off and land like a conventional aircraft significantly reducing the launch costs. Instead of relying upon multiple expendable stages during ascent, Skylon’s Synergetic Air-Breathing Rocket Engine (SABRE) combines jet and rocket propulsion technology to reach orbit. Instead of being fuelled by conventional rocket propellant carried aloft, it utilises atmospheric oxygen reducing the need to carry heavy oxygen and therefore drastically improves fuel efficiency. Once at sufficient altitude, the SABRE engine switches to rocket mode and only then starts to use onboard oxygen to reach final orbit. 

An artist’s conception of Reaction Engines’ Skylon spacecraft. Credit: Reaction Engines

Reaction Engines Limited was formed in the UK back in 1989 and focussed its attention on propulsion technology. In particular to address access issues to space and hypersonic flight. The SABRE engine they developed showed successfully that a dual-mode rocket could efficiently transition between high speed flight within the atmosphere to rocket powered flight in space. It relies upon a pre-cooler system that cools incoming air from over 1,000°C to room temperature in fractions of a second to drive high speeds without the engine over heating. 

The company is based in Oxfordshire and has to date, secured significant investments including BAE Systems, Boeing and the European Space Agency. Unfortunately, the company has been struggling to source funding to continue operations so formally entered administration on 31 October 2024. An eight week process is now underway to develop plans to restructure, sell the company or liquidate its assets. Most of its 200 employees have now been laid off. 

Source : Reaction Engines Limited

The post Reaction Engines Goes Into Bankruptcy, Taking the Hypersonic SABRE Engine With it appeared first on Universe Today.

Categories: Astronomy

Project Hyperion is Seeking Ideas for Building Humanity’s First Generation Ship

Mon, 11/11/2024 - 9:11pm

The dream of traversing the depths of space and planting the seed of human civilization on another planet has existed for generations. For long as we’ve known that most stars in the Universe are likely to have their own system of planets, there have been those who advocated that we explore them (and even settle on them). With the dawn of the Space Age, this idea was no longer just the stuff of science fiction and became a matter of scientific study. Unfortunately, the challenges of venturing beyond Earth and reaching another star system are myriad.

When it comes down to it, there are only two ways to send crewed missions to exoplanets. The first is to develop advanced propulsion systems that can achieve relativistic speeds (a fraction of the speed of light). The second involves building spacecraft that can sustain crews for generations – aka. a Generation Ship (or Worldship). On November 1st, 2024, Project Hyperion launched a design competition for crewed interstellar travel via generation ships that would rely on current and near-future technologies. The competition is open to the public and will award a total of $10,000 (USD) for innovative concepts.

Project Hyperion is an international, interdisciplinary team composed of architects, engineers, anthropologists, and urban planners. Many of them have worked with agencies and institutes like NASA, the ESA, and the Massachusetts Institute of Technology (MIT). Their competition is sponsored by the Initiative for Interstellar Studies (i4is), a non-profit organization incorporated in the UK dedicated to research that will enable robotic and human exploration and the settlement of exoplanets around nearby stars.

Artist’s concept of a generation ship. Credit: Maciej Rebisz/Michel Lamontagne

While concepts for an interstellar spacecraft go back to the early Space Age, interest in the field has grown considerably in the past two decades. This is largely due to the recent explosion in the number of known exoplanets in our galaxy, which currently stands at 5,787 confirmed planets in 4,325 star systems. This is illustrated by concepts like Breakthrough Starshot, Swarming Proxima Centauri, and the Genesis Project. These concepts leverage gram-scale spacecraft, directed energy (lasers), and lightsails to achieve speeds of up to 20% of the speed of light, allowing them to make the journey in decades rather than centuries or millennia.

However, sending crewed spacecraft to other star systems with enough passengers to settle on another planet is far more challenging. As addressed in a previous article, a spacecraft relying on known or technically feasible propulsion methods would take between 1,000 and 81,000 years to reach even the nearest star (Proxima Centauri). While some advanced concepts like Project Orion, Daedalus, and Icarus could theoretically reach Proxima Centauri in 36 to 85 years, the costs and amount of propellant needed are prohibitive.

The alternative to these “go fast” concepts is to settle in for the long ride, which may last centuries or even millennia. This necessitates a spacecraft of sufficient size capable of accommodating hundreds (or thousands) of human beings over multiple generations. To save room and reduce the mass of cargo space, the crews will need to grow much of their food and rely on life support systems that are bioregenerative in nature. In short, the ship would need to be self-sustaining so the passengers could live comfortable, healthy lives until they reached their destination.

Andreas Hein, an Associate Professor of Aerospace Engineering at the University of Luxembourg and the Chief Scientist at the Interdisciplinary Centre for Security, Reliability and Trust, is part of the Hyperion Project’s Organizing Committee. As he told Universe Today via email:

“Think about the difference between a drone and an ocean liner. Previous designs for interstellar spacecraft, such as Orion, Daedalus, and Icarus, focused on uncrewed probes with the primary objective of gathering scientific data from target star systems, including searching for signs of life. In contrast, generation ships are designed to transport a crew, with the primary goal of settling an exoplanet or other celestial body in the target star system. They also tend to be much larger than interstellar probes, though they would likely use similar propulsion systems, such as fusion-based propulsion.”

Generation Ships

The first known description of a generation ship was made by rocketry engineer Robert H. Goddard, one of the “forefathers of modern rocketry,” for whom NASA’s Goddard Space Flight Center is named. In his 1918 essay, “The Ultimate Migration,” he described an “interstellar ark” leaving the Solar System in the distant future after the Sun reached the end of its life cycle. The passengers would cryogenically frozen or in a state of induced torpor for much of the journey except for the pilot, who would be awakened periodically to steer the ship.

Goddard recommended that the ship be powered by atomic energy if the technology were realized. If not, a combination of hydrogen, oxygen, and solar energy would suffice. Goddard calculated that these power sources would allow the vessel to achieve velocities of 4.8 to 16 km/s (3 to 10 mi/s), or roughly 57,936 km/h (36,000 mph). This was followed by famed Russian rocket scientist and cosmologist Konstantin E. Tsiolkovsky, also recognized as one of the “forefathers of modern rocketry.” In 1928, he wrote an essay titled “The Future of Earth and Mankind” that described an interstellar “Noah’s Ark.”

In Tsiolkovsky’s version, the spaceship would be self-sufficient, and the crew would be awake for the journey, which would last for thousands of years. In 1964, NASA scientist Dr. Robert Enzmann proposed the most detailed concept to date for a generation ship, known as an “Enzmann Starship.“ The proposal called for a ship measuring 600 meters (2,000 feet) in length powered by a fusion thruster that uses deuterium as a propellant. According to Enzmann, this ship would house an initial crew of 200 people with room for expansion along the way.

In recent years, the concept has been explored from various angles, from biological and psychological to ethical. This included a series of studies (2017-2019) conducted by Dr. Frederic Marin of the Astronomical Observatory of Strasbourg using tailor-made numerical software (called HERITAGE). In the first two studies, Dr. Marin and colleagues conducted simulations that showed that a minimum crew of 98 (max. 500) would need to be coupled with a cryogenic bank of sperm, eggs, and embryos to ensure genetic diversity and good health upon arrival.

In the third study, Dr. Marin and another group of scientists determined that the ship carrying them would need to measure 320 meters (1050 feet) in length, 224 meters (735 feet) in radius, and contain 450 m² (~4,850 ft²) of artificial land to grow enough food to sustain them. In short, these proposals and studies establish that a generation ship and its crew must bring “Earth with them” and rely on bioregenerative systems to replenish their food, water, and air throughout generations.

Credit: Midjourney/Yazgi Demirbas Pech

As noted, most studies regarding interstellar exploration have focused on probes or ships and tended to emphasize speed over ensuring passengers could make the journey. As Hein explained, this makes the Hyperion Project the first competition to focus on generation ships and ensuring the interstellar voyagers remain healthy and safe until they arrive in a nearby star system:

“This competition is unprecedented—a true first. To our knowledge, it marks the first time a design competition specifically focused on generation ships has been launched. It builds on our team’s prior research, conducted since 2011, which addresses fundamental questions such as the required population size. This competition uniquely explores the complex interplay between generation ship technologies and the dynamics of a highly resource-constrained society.

“Most studies have focused on the technological aspects, such as propulsion and life support, while often treating the ship’s technology and onboard society as separate issues. This approach is understandable given the challenge of analyzing these interdependencies. We even got the advice to stay away. Our goal is to take an initial step toward exploring and envisioning these interdependencies. We aim to be Cayley instead of Da Vinci. Da Vinci imagined aircraft, but Cayley conceived their basic design principles, which paved the way for the Wright Brothers.”

The Competition

Registration for the competition will remain open until December 15th, 2024, and all participating teams must pay a $20 registration fee. The top three winning entries will be announced on June 2nd, 2025, and awarded $5000 for first place, $3000 for second, and $2000 for third. In addition, ten teams will receive honorary mentions for creative and innovative ideas. For more information, check out Project Hyperion’s website and the Mission Brief.

Per their mission statement, Project Hyperion is a preliminary study and feasibility assessment for crewed interstellar flight using current and near-future technologies. The goal is to inform the public about the future possibility of interstellar space travel and to guide future research and technology development. As they state on their website, the competition has the following theme:

“Humanity has overcome the great sustainability crisis in the 21st century and has transitioned into an era of sustainable abundance, both on Earth and in space. Humanity has now reached the capacity to develop a generation ship without major sacrifices. An Interstellar Starship flies by an icy planet in a nearby solar system. Going beyond the classical examination of the problem of Interstellar propulsion and structural design for a voyage lasting multiple centuries, what might be the ideal type of habitat architecture and society in order to ensure a successful trip?”

Credit: Midjourney/Yazgi Demirbas Pech

Participants will be tasked with designing the ship, its habitat, and its subsystems, including details on its architecture and society. The Project Brief describes other important Boundary Conditions, including the duration of the mission, its destination, and other important considerations. The mission duration is 250 years from launch to arrival at the target star system, consistent with the ship having advanced propulsion capable of achieving a fraction of the speed of light.

To ensure the health and safety of the crew, the ship’s habitat must have atmospheric conditions similar to Earth, protection from galactic rays, micrometeorites, and interstellar dust (necessary for relativistic space travel). The ship must also provide artificial gravity via rotating sections, but “parts of the habitat can have reduced gravity.” The habitat must also provide accommodation and decent living conditions for 1000 plus or minus 500 people throughout the trip. The habitat will also need to be designed in such a way that it can be modified to meet changing needs.

The society’s structure must allow for cultural variations, including language, ethics, family structure, beliefs, aesthetics, family structure, and other social factors. The competition also considers knowledge retention and loss relative to Earth, which they describe as “almost inevitable.” Cameron Smith, an anthropologist at Portland State University and the University of Arizona’s Center for Human Space Exploration (CHaSE), is also a member of Project Hyperion’s Organizing Committee. As he explained to Universe Today:

“[T]he situation of a population, let’s say thousands or even 1500 people, traveling in isolation for centuries would be unique to the human experience. So just as we plan for the health of the architecture and the hardware, maintaining them to keep them in a good state over this time span, we can plan for the health and maintenance of both biology and culture. And we have an excellent guide which is evolution.

“Evolution is at the heart of all life sciences, and it also, in many ways, applies to cultural change through time. Biology evolves, and cultures evolve. And we have learned how to manage our cultures on Earth to fit a wide variety of situations.”

“The idea, however, is to get people thinking about how culture might be adjusted for the unusual conditions I’ve outlined. Separation from Earth, separation from other populations of humans, except by radio or video communication – which will become less and less as they get farther from Earth – what could change through time of the voyage that would require cultural adjustment?”

Credit: Midjourney/Yazgi Demirbas Pech

Throughout the trip, the population must also have access to basic products (clothing, shelter, etc.). The mass of the habitat is to be as low as possible, reliable over the entire duration of the journey, and include redundant systems. The generation ship’s target destination is a rocky planet in a nearby star system (like Proxima b). In an interesting twist, the competition stresses that this planet will have an artificial ecosystem created by a precursor probe, à la Project Genesis. As a result, the crews will not require any significant genetic or biological adaptations to survive in that ecosystem. As Hein explained:

“250 years in a tin can and staying happy, aka. can a society thrive in a severely resource-constrained environment? Answering this question is essential for designing a generation ship and may also offer insights into sustainable futures on Earth. From my perspective, there has been a significant lack of imaginative solutions to this challenge.’250 years in a tin can and staying happy, aka, can a society thrive in a severely resource-constrained environment?’

Answering this question is essential for designing a generation ship and may also offer insights into sustainable futures on Earth. From my perspective, there has been a significant lack of imaginative solutions to this challenge.”

“We also hope to raise awareness of the complexities underlying today’s technologies. Which technologies could or should be preserved on a generation ship, and which may be lost? Research shows that a society’s population size affects the diversity and complexity of its technologies. Most modern technologies require intricate supply chains involving numerous companies, infrastructure, and regulatory systems. Therefore, a generation ship will likely rely on low-tech solutions unless disruptive technologies, like molecular manufacturing or Standard Template Constructs (as depicted in Warhammer 40k), become feasible.”

An Interdisciplinary Approach

A major focus of the competition is interdisciplinary research, reflective of the organizing committee itself. This has become a trend in space research, thanks in large part to the rise of the commercial space industry. For many companies and non-profits today, traditional research is expanding beyond aerospace engineering and incorporating architecture and interior design, biology, sociology, psychology, agriculture, and other disciplines to create concepts that will allow for healthy and sustainable living in space.

Credit: Midjourney/Yazgi Demirbas Pech

Per the rules, teams must consist of at least one architectural designer, engineer, and social scientist (a sociologist, anthropologist, etc.). As Yazgi Demirbas Pech, an architect and designer with the Organizing Committee, explained:

“We hope this competition will inspire greater interdisciplinary collaboration, emphasizing the value of fields such as architecture and social sciences—especially critical in planning for long-duration, long-distance missions. A holistic approach that integrates these diverse fields can contribute to more sustainable and human-centered solutions for space exploration.

“Unlike traditional architectural practices on Earth, space architecture requires a delicate balance between strict technical constraints—such as limited physical space, extreme environmental conditions, and restricted resources—and the essential human needs for comfort, safety, and psychological well-being. Here, architecture becomes a life-sustaining element, enabling people to live, work, and thrive across vast distances and timescales.

“Through this competition, we invite teams to challenge conventional design principles and redefine what “home” means among the stars. Including architects or architecture students on teams will undoubtedly add fresh perspectives to this thought-provoking competition.”

Solving for Space Solves for Earth

Another important aspect of the competition is the desire to inspire ideas that will also have applications and benefits here on Earth. This is another crucial aspect of the future of space exploration, which includes plans for creating outposts on the Moon, Mars, and beyond. Like a generation ship, missions operating farther from Earth cannot rely on regular resupply missions sent from Earth. This means that habitats must be as self-sufficient as possible and ensure that inhabitants have enough air, water, and food to live comfortably.

For decades, scientists and planners have looked to Earth’s natural environment for inspiration. This was the purpose of the Biosphere 2 project, which conducted two experiments between 1991 and 1994 in which volunteers lived in a sealed biome that mimics Earth’s many environments. Since 2007, the University of Arizona has used the facility to conduct research through its CHaSE program while remaining open to the public.

Credit: Midjourney/Yazgi Demirbas Pech

“Since the 1990s, [Biosphere 2] has been a research center for closed ecosystems as though on a starship, and the research here continues. [I am] actually residing at the biosphere until January, and I am looking at the stars and engaged in all of this right now,” said Smith, who wrote to Universe Today from the facility. As he went on to note, research from this experiment and similar studies have significant applications for life here on Earth, mainly because there is no margin for error in space:

“[T]he planning and preparation going into the starship in terms of its culture and biological protections for the offspring would be very carefully designed to give the greatest protections to them, perhaps in ways more specifically tailored to their survival and good health than in any culture ever on Earth. On the interstellar voyage, things must go just right to survive over multiple generations in the closed ecosystem, so planning and preparation would have to be very thorough.”

Since failure in space often means death, especially when people are stationed far from Earth where rescue missions would take too long to reach them, the technologies future explorers and settlers rely on must be regenerative, fail-proof, and sustainable over time. This research and development will have direct benefits when it comes to the most pressing problems we face here on Earth: climate change, overpopulation, poverty and hunger, and the need for sustainable living. As Pech emphasized:

“I believe that thinking beyond Earth can offer valuable insights into how we might improve life here on ‘spaceship Earth.’ Just as in space, where we face numerous challenges, our planet requires innovative approaches to foster harmony and resilience amidst current global conflicts and challenges.”

There’s also the added benefit of stimulating questions about life in the Universe and where extraterrestrial civilizations (ETCs) could already be traveling among the stars. For decades, scientists have explored these questions as part of the Fermi Paradox. As Hein explained:

“Finally, just as Project Daedalus demonstrated the theoretical feasibility of interstellar travel, we aim to establish a similar ‘existence proof’ for human travel to the stars. Achieving this will add new perspectives to the Fermi Paradox: if we can envision crewed interstellar travel today, a more advanced civilization should have achieved it already. So, where are they?”

Those interested in the competition or have more questions are encouraged to contact the Initiative for Interstellar Studies at info@i4is.org. The i4is will remain open to Q&A until December 1st, 2024.

Further Reading: Project Hyperion

The post Project Hyperion is Seeking Ideas for Building Humanity’s First Generation Ship appeared first on Universe Today.

Categories: Astronomy

How Did Supermassive Black Holes Get So Big, So Early? They Might Have Had a Head Start

Mon, 11/11/2024 - 4:23pm

Supermassive Black Holes (SMBHs) can have billions of solar masses, and observational evidence suggests that all large galaxies have one at their centres. However, the JWST has revealed a foundational cosmic mystery. The powerful space telescope, with its ability to observe ancient galaxies in the first billion years after the Big Bang, has shown us that SMBHs were extremely massive even then. This contradicts our scientific models explaining how these behemoths became so huge.

How did they get so massive so early?

Black holes of all masses are somewhat mysterious. We know that massive stars can collapse and form stellar-mass black holes late in their lives. We also know that pairs of stellar-mass black holes can merge, and we’ve detected the gravitational waves from those mergers. So, it’s tempting to think that SMBHs also grow through mergers when galaxies merge together.

The problem is, in the early Universe, there wasn’t enough time for black holes to grow large enough and merge often enough to produce the SMBHs. The JWST has shown us the errors in our models of black hole growth by finding quasars powered by black holes of 1-10 billion solar masses less than 700 million years after the Big Bang.

Astrophysicists are busy trying to understand how SMBHs became so massive so soon in the Universe. New research titled “Primordial black holes as supermassive black holes seeds” attempts to fill in the gap in our understanding. The lead author is Francesco Ziparo from the Scuola Normale Superiore di Pisa, a public university in Italy.

This artist’s conception illustrates a supermassive black hole (central black dot) at the core of a young, star-rich galaxy. Observational evidence suggests all large galaxies have one. Image credit: NASA/JPL-Caltech

There are three types of black holes: Stellar-mass black holes, intermediate-mass black holes (IMBHs), and SMBHs. Stellar-mass black holes have masses ranging from about five solar masses up to several tens of solar masses. SMBHs have masses ranging from hundreds of thousands of solar masses up to millions or billions of solar masses. IMBHs are in between, with masses ranging from about one hundred to one hundred thousand solar masses. Researchers have wondered if IMBHs could be the missing link between stellar-mass black holes and SMBHs. However, we only have indirect evidence that they exist.

This is Omega Centauri, the largest and brightest globular cluster that we know of in the Milky Way. An international team of astronomers used more than 500 images from the NASA/ESA Hubble Space Telescope spanning two decades to detect seven fast-moving stars in the innermost region of Omega Centauri. These stars provide compelling new evidence for the presence of an intermediate-mass black hole. Image Credit: ESA/Hubble & NASA, M. Häberle (MPIA)

There’s a fourth type of black hole that is largely theoretical, and some researchers think they can help explain how the early SMBHs were so massive. They’re called primordial black holes (PBHs.) Conditions in the very early Universe were much different than they are now, and astrophysicists think that PBHs could’ve formed by the direct collapse of dense pockets of subatomic matter. PBHs formed before there were any stars, so aren’t limited to the rather narrow mass range of stellar-mass black holes.

Artist illustration of primordial black holes. NASA’s Goddard Space Flight Center

“The presence of supermassive black holes in the first cosmic Gyr (gigayear) challenges current models of BH formation and evolution,” the researchers write. “We propose a novel mechanism for the formation of early SMBH seeds based on primordial black holes (PBHs).”

Ziparo and his co-authors explain that in the early Universe, PBHs would’ve clustered and formed in high-density regions, the same regions where dark matter halos originated. Their model takes into account PBH accretion and feedback, the growth of dark matter halos, and dynamical gas friction.

In this model, the PBHs are about 30 solar masses and are in the central region of dark matter (DM) halos. As the halos grow, baryonic matter settles in their wells as cooled gas. “PBHs both accrete baryons and lose angular momentum as a consequence of the dynamical friction on the gas, thus gathering in the central region of the potential well and forming a dense core,” the authors explain. Once clustered together, a runaway collapse occurs that ends up as a massive black hole. Its mass depends on the initial conditions.

Planted soon enough, these seeds can explain the early SMBHs the JWST has observed.

This figure from the research illustrates how PBHs could form the seeds for SMBHs. (Left) As the gas cools, it settles into the center of the dark matter gravitational potential, and the PBHs become embedded at the center. (Middle) The PBHs lose angular momentum due to the gas’s dynamic friction and concentrate in the core of the DM halo. (Right) PBH binaries form and merge rapidly because of their high density. The end result is a runaway merger process that creates the seeds of SMBHs. Image Credit: Ziparo et al. 2024.

There’s a way to test this model, according to the authors.

“During the runaway phase of the proposed seed formation process, PBH-PBH mergers are expected to copiously emit gravitational waves. These predictions can be tested through future Einstein Telescope observations and used to constrain inflationary models,” they explain.

The Einstein Telescope or Einstein Observatory is a proposal from several European research agencies and institutions for an underground gravitational wave (GW) observatory that would build on the success of the laser-interferometric detectors Advanced Virgo and Advanced LIGO. The Einstein Telescope would also be a laser interferometer but with much longer arms. While LIGO has arms four km long, Einstein would have arms 10 km long. Those longer arms, combined with new technologies, would make the Telescope much more sensitive to GWs.

The Einstein Telescope should open up a GW window into the entire population of stellar and intermediate-mass black holes over the entire history of the Universe. “The Einstein Telescope will make it possible, for the first time, to explore the Universe through gravitational waves along its cosmic history up to the cosmological dark ages, shedding light on open questions of fundamental physics and cosmology,” the Einstein website says.

A thorough understanding of SMBHs is a ways away, but it’s important to understand them because of their role in the Universe. They help explain the universe’s large-scale structure by influencing the distribution of matter on large scales. The fact that they appeared so much earlier in the Universe than we thought possible shows that we have a lot to learn about SMBHs and how the Universe has evolved to the state it’s in now.

The post How Did Supermassive Black Holes Get So Big, So Early? They Might Have Had a Head Start appeared first on Universe Today.

Categories: Astronomy

A Mission to Triton and Neptune Would Unlock Their Mysteries

Mon, 11/11/2024 - 3:10pm

A town in the Austrian Alps might not seem like the most conducive place to come up with daring space missions. But, for the last 40 years, students and professors have been gathering to do just that in Alpbach, just north of the Lichtenstein/Austrian border. One outcome of the Alpbach Summer School this year was an idea for a combined Neptune / Triton explorer mission to take advantage of existing technology developed for the JUICE missions. Before we get into the technical details of the mission, though, let’s dive into why scientists should care about the Neptunian system in the first place.

The last time we visited Neptune was with Voyager 2 back in 1989, and it was launched 12 years before that in 1977. Technology has advanced significantly since then, and the limited amount of data Voyager collected at Neptune provided exciting insights into the planet. For example, its magnetosphere is tilted by 47 degrees. Also, Neptune’s interior remains opaque, with our best guess being that it differs from the other gas giants. However, a lack of data makes further speculation difficult.

Triton, Neptune’s moon, is also interesting in its own right. It has a retrograde orbit, which implies that it is a captured Trans-Neptunian Object rather than a moon that formed from some violent event on Neptune itself. It shows a significant amount of geological activity and shot a series of dark plumes into space during Voyager’s flyby, whose composition remains unknown.

There are plenty of mission ideas for visiting Neptune and Triton – including the Trident mission at NASA.

Visiting these faraway worlds requires plenty of foresight, and many missions have been proposed. The “Blue” team at the Alpbach summer school developed a two-pronged approach for this mission design – the Triton Unveiler & Neptune Explorer (TUNE). This orbiter would hold most of the mission’s primary instrumentation and the Probe for Inner Atmospheric Neptune Observations (PIANO). One of the classes at the Summer School was space exploration acronym training.

TUNE, the orbiter, will be placed into a trajectory allowing it to orbit Neptune 600 times while using Triton to course-correct during its 40 flybys of the smaller moon. Its payload would include a standard suite of sensors, including a radiometer, spectrometer, altimeter, and many other meters. These instruments would help it complete its nine science objectives, which range from measuring temperature and pressure differences in Neptune’s atmosphere to determining Triton’s surface composition.

A second craft will help with several of those missions. PIANO has its own suite of meters, including a Nephelometer and helium sensor. It is designed to be shot into Neptune and send data back to TUNE during its descent, allowing scientists to get a first glimpse into the interior of this enigmatic world.

Fraser discusses the Voyager’s collected data on Neptune.

Thanks to the Jupiter Icy Moons Explorer (JUICE) mission from ESA, most of the mission’s technologies already exist and have been flight-proven. While that lowers the overall development cost of the mission, other factors play into a sense of urgency for launch. In the 2070s, the part of Triton that emits those dark plumes will enter a night phase that it will not leave for years, making it necessary to get there before that nuance of orbital mechanics makes the mission goals more difficult.

Given the long development time for some missions and the decade-plus journey to reach the last planet in the solar system, the sooner scientists and engineers start working toward the mission, the better. But so far, none of the big space agencies have picked up the idea as a fully-fledged mission concept. Though we will eventually send another probe to Neptune at some point, unless one of them does pick up this mission, TUNE-PIANO might remain only a dream of one summer in the Austrian Alps.

Learn More:
M. Acurcio et al – The TUNE & PIANO Mission
UT – 10 Interesting Facts About Neptune
UT – What Is The Surface of Neptune Like?
UT – An Ambitious Mission to Neptune Could Study Both the Planet and Triton

Lead Image:
Global color mosaic of Neptune’s largest moon, Triton, taken by NASA’s Voyager 2 in 1989.
Credit: NASA/JPL-Caltech/USGS

The post A Mission to Triton and Neptune Would Unlock Their Mysteries appeared first on Universe Today.

Categories: Astronomy