Astronomy

The universe is being revealed in exquisite detail with the current generation of large optical telescopes.

Interview with NASA/JPL's systems engineer Bobak Ferdowsi on his "3 Body Problem" cameo.

Black hole singularities defy the laws of physics. New research presents a bold solution to this puzzle: Black holes may actually be a theoretical type of star called a 'gravastar,' filled with universe-expanding dark energy.

It seemed like night, but part of the sky glowed purple.

NASA is actively working to return surface samples from Mars in the next few years, which they hope will help us better understand whether ancient life once existed on the Red Planet’s surface billions of years ago. But what about atmospheric samples? Could these provide scientists with better information pertaining to the history of Mars? This is what a recent study presented at the 55th Lunar and Planetary Science Conference hopes to address as a team of international researchers investigated the significance of returning atmospheric samples from Mars and how these could teach us about the formation and evolution of the Red Planet.

Here, Universe Today discusses this research with the study’s lead author, Dr. Edward Young, who is a professor in the Department of Earth, Planetary, and Space Sciences at UCLA, and study co-author, Dr. Timothy Swindle, who is a Professor Emeritus in the Lunar & Planetary Laboratory at the University of Arizona, regarding the motivation behind the study, how atmospheric samples would be obtained, current or proposed missions, follow-up studies, and whether they think life ever existed on the Red Planet. Therefore, what was the motivation for the study?

Dr. Young tells Universe Today, “We learn a lot about the origin of a planet from its atmosphere as well as its rocks. In particular, isotope ratios of certain elements can constrain the processes leading to the formation of the planet.”

Credit: European Space Agency

Dr. Swindle follows this with, “There are two basic types of motivation. One is that we’re planning on bringing all these rock samples, and we’re going to be interested in knowing how they’ve interacted with the atmosphere, but we can’t figure that out without knowing the composition of the atmosphere in detail. So, we need an atmospheric sample to know what the rocks might have been exchanging elements and isotopes with. But we’d also like to have a sample of the Martian atmosphere to answer some basic questions about processes that have occurred, or are occurring, on Mars. For example, Martian meteorites contain trapped atmospheric noble gases, like krypton and xenon. But it appears that there are at least two different “atmospheric” components in those meteorites.”

For the study, the researchers proposed several benefits of returning a Mars atmospheric sample to Earth, including atmospheric samples being among the NASA Perseverance (Percy) rover sample tubes, gaining insight into potential solar gar within the Martian interior, evolutionary trends in atmospheric compositions, nitrogen cycling, and sources of methane on Mars. For the Percy atmospheric sample, also known as Sample No.1 “Roubion”, the study notes how this sample was obtained after Percy tried to collect a rock core sample but ended up collecting atmospheric gases instead. Additionally, the study proposes the lack of leakage the sample tube will experience while awaiting its return to Earth and the gases present within the sample are ideal for analysis once returned to Earth, as well. But aside from the Percy rover sample, how else could a Martian atmosphere sample be obtained?

“At least two other ideas for collecting a sample of Martian atmosphere have been suggested,” Dr. Swindle tells Universe Today. “One is to fly a spacecraft through the Martian atmosphere, collect a sample as it goes through, then return it to Earth. The other is to have a sample return “cannister” (it doesn’t have to be any bigger than a Perseverance tube) that has valves and a (Martian) air compressor. You could land it on the surface of Mars, open the valve to the atmosphere, turn on the compressor, and get a sample that has hundreds or thousands of times as much Martian atmosphere as a volume that is just sealed without compression, as Perseverance has done, and hopefully will do again.”

Dr. Swindle and Dr. Young both mention the Sample Collection for Investigation of Mars (SCIM) mission, which was proposed in 2002 by a team of NASA and academic researchers with the goal of collecting atmospheric samples at an altitude of 40 kilometers (25 miles) above the Martian surface and return them to Earth for further analysis. While SCIM was selected as a semi-finalist for the 2007 Mars Scout Program, it was unfortunately not selected for further development, and both Dr. Young and Dr. Swindle tell Universe Today there are currently no atmospheric sample missions being planned aside from the Percy rover sample. Therefore, what follow-up studies from this research are currently underway or being planned?

Dr. Swindle and Dr. Young both mention how efforts are being made to collect small quantities of atmospheric gas due to the small size of the sample tubes, with Dr. Swindle telling Universe Today, “A big set of questions right now is how good a sealed Perseverance tube would be at containing an atmospheric sample. How good is the seal? Might the tube spring a leak on a hard landing? Would some molecules in the Martian atmosphere stick to the coatings of the tubes? There’s been some activity on all of these questions, and so far, the answers have all been good – it looks like those Perseverance tubes may do well, even though they weren’t really designed with atmospheric sampling in mind.”

As noted, the purpose of obtaining and returning an atmospheric sample from Mars could help scientists better understand the formation and evolution of the Red Planet. While present-day Mars is a very cold and dry world with an atmosphere that is a fraction of the Earth’s atmosphere, with liquid water being unable to exist on the surface, along with no active volcanism, as well. However, significant evidence obtained from landers, rovers, and orbiters over the last several decades point to a much different Mars billions of years ago after it first formed. This included an active interior that produced a magnetic field that shielded the surface from harmful solar and cosmic radiation, a much thicker atmosphere being replenished from active volcanism, and flowing liquid water, all of which potentially led to the existence of some forms of life on the surface.

However, given Mars’ small size (half of Earth), this means its internal heat cooled off much faster (possibly over millions of years), resulting in volcanism becoming inactive and the dissipation of the magnetic field the interior activity was driving, the latter of which led to harmful solar and cosmic radiation stripping the atmosphere, with the surface liquid water evaporating to space along with it. Therefore, do Dr. Young and Dr. Swindle believe life ever existed on Mars, and will we ever find it?

Dr. Young tells Universe Today, “I really don’t know.  I think microbial life sometime in the past, or even now, is a reasonable hypothesis but we don’t have enough information.”

Dr. Swindle also echoes his uncertainty whether life ever existed on Mars, but elaborates by telling Universe Today, “If there hasn’t, why did life start so early on Earth, but didn’t start on Mars, which had a similar climate at the time. If there has been, how similar is it to life on Earth? Since Earth and Mars are always exchanging rocks because of impacts, is life on Earth related to life on Mars? If it has existed, it will be tough to find. But an atmospheric sample could help. For instance, there seems to be methane in the Martian atmosphere. Most, but not all, of the methane in Earth’s atmosphere is biological, and analyzing the relative ratios of the isotopes of carbon or hydrogen is one of the best ways to figure that out.”

When will we obtain an atmospheric sample of Mars and what will it teach us about the formation and evolution of the Red Planet in the coming years and decades? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

The post Could Martian atmospheric samples teach us more about the Red Planet than surface samples? appeared first on Universe Today.

Black holes seem to provide endless fascination to astronomers. This is at least partly due to the extreme physics that takes place in and around them, but sometimes, it might harken back to cultural touchpoints that made them interested in astronomy in the first place. That seems to be the case for the authors of a new paper on the movement of jets coming out of black holes. Dubbing them “Death Star” black holes, researchers used data from the Very Long Baseline Array (VLBA) and the Chandra X-ray Observatory to look at where these black holes fired jets of superheated particles. And over time the found they did something the fiction Death Star could also do – move.

The black holes at the center of the study were supermassive ones at the centers of galaxies. Importantly, they were all surrounded by hot gases that were visible to Chandra’s X-ray sensors. The jets themselves were clearly visible in the data, but there was other important information hiding in it—namely, pockets free from gas, which had been pushed away by the jets.

Each black hole has particle jets in two opposing directions. As those jets push away gas and dust, they open up a pocket in space surrounding the black hole. These are visible in the X-ray data due to a lack of signal from those regions. The researchers hypothesized that the jets should align with the pockets of free space they create.

Black holes have been known to spin for a while – as Fraser discusses.

However, they found that, in at least 6 of the 16 black holes they were studying, the beams had completely changed direction such that the pockets of missing gas no longer aligned with the jets currently emitted from the black hole. In some cases, these changes added up to a 90-degree shift in the direction the jets were facing. What’s even more impressive, they seemed to move on a relatively small time scale, with estimates ranging from 1 to 10 million years. That is a blink of an eye for a black hole over 10 billion years old.

So why is this important? Cosmologists theorize that these disruptive jets put an upper limit on the number of stars that form in the host galaxy of the black holes. They don’t let the gas and dust surrounding them cool down enough to start to form stars and rocky planets. So, while it isn’t clear if the jets of particles themselves are roasting any formed planets like the actual Death Star, it is clear that moving the jets around would cause an even more massive disruption in the star-forming process. In theory, this would mean that galaxies containing these moving jets would have fewer stars, but that is a study for another paper.

Understanding exactly why this is happening might also need to be researched in another paper, but the authors have a few theories. Matter orbiting around the black hole and falling into it could cause the black hole to rotate, causing the jets it emits to move with it. 

How a black hole forms could hold the key to understanding why its jets move over time. Fraser discusses how that happens.

Another explanation is that the gas is moving around the galaxy without being impacted by the beams. In essence, the “cavities” of no gas in a galaxy are remnants of other cosmological forces and have nothing to do with the black hole beams. However, the authors don’t think this is likely because the galaxy mergers that could be one source of causing the “sloshing” happened in the galaxies that had the moving beams and those that didn’t. One would expect the cavities to be present in both types if they were caused by galaxies merging rather than moving jets of particles.

As always, there is more science to do. Thanks to the wonderful world of video streaming, a whole generation of new scientists inspired by the same Death Star could do it.

Learn More:
Chandra – Spotted: ‘Death Star’ Black Holes in Action
Ubertosi et al. – Jet reorientation in central galaxies of clusters and groups: insights from VLBA and Chandra data
UT – It’s Confirmed. M87’s Black Hole is Actually Spinning
UT – The Milky Way’s Black Hole is Spinning as Fast as it Can

Lead Image:
Image from Chandra’s X-Ray and VLBA’s radio data set of a black hole’s jets with “cavities” surrounding it.
Credit: X-ray: NASA/CXC/Univ. of Bologna/F. Ubertosi; Inset Radio: NSF/NRAO/VLBA; Image Processing: NASA/CXC/SAO/N. Wolk

The post Black Holes are Firing Beams of Particles, Changing Targets Over Time appeared first on Universe Today.

Skywatchers who plan to rise early and step outside on June 3 expecting to see a stunning display of visible planets will be quite disappointed, at the very least.

Here's what it was like seeing Ridley Scott's "Alien" on opening day in 1979, in honor of the iconic sci-fi horror film's 45th anniversary.

Two countries—Slovenia and Venezuela—have lost all of their glaciers. It is a grim benchmark showing the progression of climate change

On Episode 112 of This Week In Space, Rod and Tariq talk with Rob Manning, Chief Engineer Emeritus of NASA's Jet Propulsion Laboratory, about Mars exploration and, in particular, Mars Sample Return.

An explanation of Towel Day and its meaning in the world of Douglas Adams' "The Hitchhiker's Guide to the Galaxy."

The most common test of statistical significance originated from the Guinness brewery. Here’s how it works

Jared Isaacman, the billionaire funder and commander of the Polaris Program missions, spoke on social media recently about why he wants a Hubble Space Telescope mission.

North Celestial Aurora

On May 20th, 2024, an iceberg measuring 380 square kilometers (~147 mi2) broke off the Brunt Ice Shelf in Antarctica. This event (A-83) is this region’s third significant iceberg calving in the past four years. The first came In 2021, when A-74 broke off the ice sheet, while an even larger berg named A-81 followed in 2023. The separation of this iceberg was captured by two Earth Observation satellites – the ESA’s Copernicus Sentinel-1 and NASA’s Landsat 8 satellites – which provided radar imaging and thermal data, respectively.

The iceberg has been officially designated A-83 by the U.S. National Ice Center, which assigns names based on the Antarctic quadrant where the iceberg was first sighted. Since Brunt is located in the eastern Weddell Sea, its bergs receive an ‘A’ designation while the numbers are assigned sequentially. Routine monitoring of ice shelves by satellites allows scientists to track the effects of Climate Change in remote regions like Antarctica. In particular, scientists can monitor how ice shelves retain their structural integrity in response to changing ice dynamics and increases in atmospheric and ocean temperatures.

Brightness temperature data from the U.S. Landsat 8 mission. Credit: ESA/USGS

This calving event (like its predecessors) was caused by the weakening of the ice at the McDonald Ice Rumples and the extension of the ‘Halloween Crack’ into the ice shelf. The Copernicus Sentinel-1 mission relies on radar imaging to return images throughout the year, regardless of whether it’s day or night. This is especially important during the winter when there is virtually no sunlight for six months (known as Antarctic Night). Missions like Landsat 8 rely on thermal imaging to help scientists characterize ice sheet thickness.

As the image above shows, the thinner ice appears warmer since it is closer in temperature to open water, while thicker continental ice appears darker. The temperature differences between the ocean and ice sheets also help scientists identify where the calving line is. Fortunately, the iceberg does not threaten the British Antarctic Survey’s Halley VI Research Station, an international research platform that observes Earth, atmospheric, and space weather. While it is still located on the Brunt Ice Shelf, the station was relocated in 2017 to the Caird coast after the outer ice shelf was deemed unstable.

The ongoing loss of Antarctic ice is one of the clearest indications of rising global temperatures and a dire warning. In addition to contributing to rising sea levels, coastal flooding, and extreme weather, the loss of polar ice leads to additional solar radiation being absorbed by Earth’s oceans, causing temperatures to rise further. Monitoring the polar ice sheets is vital to adaptation and mitigation strategies, as spelled out in the IPCC’s Sixth Assessment Report (AR6).

Further Reading: ESA

The post Another Giant Antarctic Iceberg Breaks Free appeared first on Universe Today.

The James Webb Space Telescope has found three of the universe's earliest galaxies, and they could reveal a lot about galactic dynamics. Here's how.

NASA and Boeing are still working through "complicated" issues arising from a small Starliner spacecraft helium leak. Launch is June 1, but that's pending a flight readiness review.

Four zebrafish are alive and well after nearly a month in space aboard China’s Tiangong space station. As part of an experiment testing the development of vertebrates in microgravity, the fish live and swim within a small habitat aboard the station.

While the zebrafish have thus far survived, they are showing some signs of disorientation. The taikonauts aboard Tiangong – Ye Guangfu, Li Cong, and Li Guangsu – have reported instances of swimming upside down, backward, and in circular motions, suggesting that microgravity is having an effect on their spatial awareness.

The zebrafish were launched aboard Shenzhou-18, which carried them, as well as a batch of hornwort, to orbit on April 25, 2024. The aim of the project is to create a self-sustaining ecosystem, studying the effects of both microgravity and radiation on the development and growth of these species.

As a test subject, zebrafish have several advantages. Their short reproductive and development cycle, and transparent eggs, allow scientists to study their growth quickly and effectively, and their genetic makeup shares similarities with humans, potentially offering insights that are relevant to human health. The zebrafish genome has been fully sequenced, and for these reasons zebrafish are commonly used in scientific experiments on Earth. Seeing how these well-studied creatures behave in such an extreme environment may have a lot to tell us about the life and development of vertebrates across species while exposed to microgravity.

The developmental stages of a zebrafish (danio rerio). Ed Hendel, Wikimedia Commons.

The taikonauts aboard Tiangong perform feeding and water sampling at regular intervals, and cameras allow scientists on the ground to monitor the aquarium.

This is not the first time fish have been to space. Starting in 2012, a Japanese research project brought medaka and zebrafish to the International Space Station for study in a similar aquatic habitat. The results of those studies revealed a decrease in bone density in the fish within just ten days. Human astronauts experience similar effects in orbit, though not on such quick time scales, and they can be mitigated somewhat through rigorous exercise routines.

Earlier fish in space include a mummichog aboard Skylab 3 in 1973 (and again in 1975 aboard Apollo-Soyuz), and zebrafish aboard the Soviet space station Salyut 5 in 1976. A variety of fish reached orbit aboard space shuttles in the 1990s, too.

The health and sustainability of animal life in space is a key area of research for human spaceflight efforts. If humans are to travel on long-term space missions, like those required to reach Mars, then understanding the biological implications of space travel is vital. These zebrafish are the latest in a long line of experiments undertaken in this pressing area of research.  

Learn More:

Gong Zhe “Aquatic antics: Fish exhibit disorientation in China Space Station.” CGTN.

The post Fish are Adapting to Weightlessness on the Chinese Space Station appeared first on Universe Today.

A new catalog of the masses and widths of 126 new exoplanets showcases the extreme and exotic nature of worlds beyond the solar system.