Astronomy

The Proba-3 mission consists of two spacecraft that will fly in close formation to study the sun, with the shadow of one creating an artificial solar eclipse from the perspective of the other

The Proba-3 mission consists of two spacecraft that will fly in close formation to study the sun, with the shadow of one creating an artificial solar eclipse from the perspective of the other

Pluto may have been downgraded from full-planet status, but that doesn’t mean it doesn’t hold a special place in scientist’s hearts. There are practical and sentimental reasons for that – Pluto has tantalizing mysteries to unlock that New Horizons, the most recent spacecraft to visit the system, only added to. To research those mysteries, a multidisciplinary team from dozens of universities and research institutes has proposed Persephone – a mission to the Pluto system that could last 50 years.

New Horizons rocketed past the Pluto system in 2015, which is now technically considered part of the Kuiper Belt. The mission collected data on the dwarf planet and its unique moon, Charon. Scientists have now had time to analyze the data from that mission, and it left them wanting more—in particular, data about some of the surface features that they observed.

Persephone has four main scientific questions it is designed to answer, according to a paper published back in 2021:

1) “How has the population of the Kuiper Belt evolved?”
2) “What are the particle and magnetic field environments of the Kuiper Belt?”
3) “How have the surfaces of both Pluto and Charon changed?”
4) “What are the internal structures of Pluto and Charon?”

Fraser discusses what we learned about Pluto from New Horizons

That last one might be the most intriguing, as the answer for Pluto’s internal structure might be that it has a subsurface ocean despite being so far away from the Sun. There is already some evidence for this, as Pluto appears to have an active surface, and an ice sheet called Sputnik Planitia could potentially be caused by a subsurface ocean. We don’t have enough data yet to prove it.

That is what Persephone is designed to provide. Unfortunately, with the unforgiving logic of orbital mechanics and current constraints on propulsion technology, any such mission would take multiple decades, even with a gravity assist from Jupiter. The mission design for Persephone has been operational for almost 31 years, including a 28-year cruise phase and a three-year orbit period around Pluto and Charon. It could then have an extended operational mission to visit other Kuiper belt objects to help constrain the variance in the different kinds of objects in that massive section of space.

That travel time could be helped by the development of a more effective nuclear electric propulsion system, which could shave up to 2 years off it even with a heavier payload than currently planned for Persephone. Such a system has been described but might not be available for the planned 2031 launch date for Persephone on board an SLS rocket.

Fraser discusses the longevity of spacecraft, which will definitely be a consideration for any future missions to Pluto.

Persephone will take a suite of sensors, no matter its propulsion system, which can be “brought to bear on any and every object encountered during the mission,”. According to the flight plan, that would include Jupiter and its moons. These sensors include cameras, spectrometers, radar, magnetometers, and altimeters to meet the mission’s necessary science objectives.

A critical differentiator for the mission is that it is designed to be an orbiter rather than a flyby. According to the authors, much of the data needed to be collected would be infeasible with the short period a flyby would provide with the system. An orbiter would be able to stick around and collect data over the three-year period about both Pluto and Charon, including their active surface dynamics.

This proposal is just one of many mission proposals to the outer planets seeking further funding, and a preliminary estimate of $3bn puts it in the higher range of those missions. But if it is funded in some capacity, it could provide answers to the questions that New Horizons posed, even if it would take several decades to reach them.

Learn More:
Howett et al – Persephone: A Pluto-system Orbiter and Kuiper Belt Explorer
UT – The (Dwarf) Planet Pluto
UT – NASA’s New Horizons Mission Still Threatened
UT – New Horizons is Funded Through the Decade. Enough to Explore Another Kuiper Belt Object

Lead Image:
Graphic of Pluto being visited by Persephone and all the different questions the mission could answer.
Credit – Howett et al.

The post A New Mission To Pluto Could Answer the Questions Raised by New Horizons appeared first on Universe Today.

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.

Readers give higher ratings to AI-generated poetry than the works of poets such as William Shakespeare, Walt Whitman and Emily Dickinson – perhaps because they often have more straightforward themes and simpler structure

Readers give higher ratings to AI-generated poetry than the works of poets such as William Shakespeare, Walt Whitman and Emily Dickinson – perhaps because they often have more straightforward themes and simpler structure

Visual artist Anna Von Mertens looks to astronomer Henrietta Swan Leavitt and her vision of the universe for inspiration

The crew of the U.S.S. Cerritos visits a "cursed" Starbase in 'Star Trek: Lower Decks' Season 5 episode 5.

With the help of a ruby cube and two laser beams, researchers made one ray of light cast a shadow when illuminated by the other

With the help of a ruby cube and two laser beams, researchers made one ray of light cast a shadow when illuminated by the other

Primordial black holes may be exploding throughout the universe. If we can catch them in the act, it could pave the way to new physics, a study suggests.

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.

Grab one of the coolest droids from the Phantom Menace for your Lego Star Wars collection, now at its lowest price this year.

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.

Generative AI could saddle the planet with heaps more hazardous waste

Today, an altitude chamber. Next year, the moon.

Blue Origin showed off its New Glenn rocket after its two stages were mated in the company's Florida facility. The new rocket could take off on its maiden flight as soon as November.

Thawing ice, from the high peaks to the poles, is producing extraordinarily expensive floods, infrastructure damage and losses to tourism and fishing

Today, the European Space Agency signed six contracts that will help position Greece as a key player in the field of Earth observation.

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

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