Daily Archives: July 10, 2021

Using AI driven data analysis to peel back the noise and find the actual shape of the Universe. Credit: The Institute of Statistical Mathematics

Japanese astronomers have developed a new artificial intelligence (AI) technique to remove noise in astronomical data due to random variations in galaxy shapes. After extensive training and testing on large mock data created by supercomputer simulations, they then applied this new tool to actual data from Japans Subaru Telescope and found that the mass distribution derived from using this method is consistent with the currently accepted models of the Universe. This is a powerful new tool for analyzing big data from current and planned astronomy surveys.

Wide area survey data can be used to study the large-scale structure of the Universe through measurements of gravitational lensing patterns. In gravitational lensing, the gravity of a foreground object, like a cluster of galaxies, can distort the image of a background object, such as a more distant galaxy. Some examples of gravitational lensing are obvious, such as the Eye of Horus. The large-scale structure, consisting mostly of mysterious dark matter, can distort the shapes of distant galaxies as well, but the expected lensing effect is subtle. Averaging over many galaxies in an area is required to create a map of foreground dark matter distributions.

But this technique of looking at many galaxy images runs into a problem; some galaxies are just innately a little funny looking. It is difficult to distinguish between a galaxy image distorted by gravitational lensing and a galaxy that is actually distorted. This is referred to as shape noise and is one of the limiting factors in research studying the large-scale structure of the Universe.

To compensate for shape noise, a team of Japanese astronomers first used ATERUI II, the worlds most powerful supercomputer dedicated to astronomy, to generate 25,000 mock galaxy catalogs based on real data from the Subaru Telescope. They then added realist noise to these perfectly known artificial data sets, and trained an AI to statistically recover the lensing dark matter from the mock data.

After training, the AI was able to recover previously unobservable fine details, helping to improve our understanding of the cosmic dark matter. Then using this AI on real data covering 21 square degrees of the sky, the team found a distribution of foreground mass consistent with the standard cosmological model.

This research shows the benefits of combining different types of research: observations, simulations, and AI data analysis. comments Masato Shirasaki, the leader of the team, In this era of big data, we need to step across traditional boundaries between specialties and use all available tools to understand the data. If we can do this, it will open new fields in astronomy and other sciences.

Reference: Noise reduction for weak lensing mass mapping: an application of generative adversarial networks to Subaru Hyper Suprime-Cam first-year data by Masato Shirasaki, Kana Moriwaki, Taira Oogi, Naoki Yoshida, Shiro Ikeda and Takahiro Nishimichi, 9 April 2021, Monthly Notices of the Royal Astronomical Society.DOI: 10.1093/mnras/stab982

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Astronomers Use Artificial Intelligence to Reveal the Actual Shape of the Universe - SciTechDaily

100 black holes

The globular star cluster Palomar 5 has always been strange. The cluster is one of the fluffiest known, Its less massive than other globulars and has a greater distance between its stars. It also has two long streamers of stars flowing away from the cluster. And now astronomers have found a new quirk of Palomar 5: its hiding more than 100 black holes at its center. A team of astronomers announced July 1, 2021, that this unusual globular cluster has about three times as many black holes as expected. Some 20% of the clusters mass comes from black holes. These astronomers said that, one day, the stars will be gone, and nothing will remain but the black holes.

The scientists published their study on July 5, 2021, in the peer-reviewed journal Nature Astronomy.

Palomar 5 is a globular cluster, a huge ball of stars that orbits in the halo of the Milky Way. Discovered by Walter Baade in 1950, Palomar 5 lies 65,000 light-years away from us in the direction of the constellation Serpens. This globular cluster is ancient more than 10 billion years old because it formed at the same time as the galaxy. The globular cluster is in the process of dissipating, and long streamers of stars are flowing away from it out into space.

Palomar 5 has an unusual number of black holes for a globular cluster. Mark Gieles of the University of Barcelona and lead author of the paper said:

The number of black holes is roughly three times larger than expected from the number of stars in the cluster, and it means that more than 20% of the total cluster mass is made up of black holes. They each have a mass of about 20 times the mass of the sun, and they formed in supernova explosions at the end of the lives of massive stars, when the cluster was still very young.

The black-hole heavy cluster is losing stars as they flow away from the cluster out into space, leaving long tails visible in deep-sky surveys. Tidal streams, as they are called, are made up of stars that were ejected from disrupting star clusters or dwarf galaxies. Palomar 5 is the only globular star cluster displaying tidal streams. But in the last few years, astronomers have discovered almost 30 thin tidal streams unconnected to clusters in the Milky Ways halo. As Gieles said:

We do not know how these streams form, but one idea is that they are disrupted star clusters. However, none of the recently discovered streams have a star cluster associated with them, hence we cannot be sure. So, to understand how these streams formed, we need to study one with a stellar system associated with it. Palomar 5 is the only case, making it a Rosetta stone for understanding stream formation and that is why we studied it in detail.

The higher black hole concentration may play a key in the formation of tidal streams. He continued:

We have shown that the presence of a large black hole population may have been common in all the clusters that formed the streams.

Using computer modeling, the scientists ran different simulations until they found one that matched the properties of Palomar 5. They found that Palomar 5 likely formed with a lower concentration of black holes. Then stars escaped more easily than black holes, so that the fraction of black holes to stars in the cluster increased. The black hole interactions with the stars created gravitational slingshots, which helped create its fluffy appearance and led to more stars escaping and fueling the exiting tidal stream. The scientists said that a billion years from now, just before the cluster completely dissolves, it will consist entirely of black holes.

The scientists study gives us a more complete picture for understanding globular cluster formation, the initial masses of stars and the evolution of massive stars, and has important implications for gravitational waves.

Bottom line: Scientists have discovered that the globular cluster known as Palomar 5 has a large proportion of black holes and will one day lose all its stars and be made entirely of black holes.

Source: A supra-massive population of stellar-mass black holes in the globular cluster Palomar 5

Via the University of Barcelona

Kelly Kizer Whitt has been a science writer specializing in astronomy for more than two decades. She began her career at Astronomy Magazine, and she has made regular contributions to AstronomyToday and the Sierra Club, among other outlets. Her childrens picture book, Solar System Forecast, was published in 2012. She has also written a young adult dystopian novel titled A Different Sky. When she is not reading or writing about astronomy and staring up at the stars, she enjoys traveling to the national parks, creating crossword puzzles, running, tennis, and paddleboarding. Kelly lives with her family in Wisconsin.

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Astronomers find 100 black holes in Palomar 5 - EarthSky

Not all of us have a billionaire brother who can let us hitch a ride into space, so we rely on talented photographers to give us a glimpse into the beyond.

London's Royal Museums Greenwich has unveiled the finalists for the Astronomy Photographer of the Year 2021. The astrophotography competition, which has been running for 13 years, received over 4,500 entries taken from 75 countries.

Below, you'll find a collection of the incredible finalists, with the full shortlist available on the RMG website. The winners will be announced Sept. 16 before an exhibition of the images opens at London's National Maritime Museum from Sept. 18.

From magical views of the Milky Way over French lavender fields to a truly hardcore looking sunspot, this year's finalists literally light up the skies and space around our planet. There are nine categories including skyscapes, aurorae, people and space, our sun, our moon, stars and nebulae, galaxies, and planets, comets, and asteroids.

If you're keen for more otherworldly looks into the stars, here are last year's winners.

Iceland Vortex by Larryn RaeCredit:

"Harmony" by Stefan Liebermann. A panorama of the Milky Way over lavender fields in Valensole, France.Credit: Stefan Liebermann

"Milky Way rising over Durdle Door" byAnthony Sullivan. Taken in Dorset in England.Credit: Anthony Sullivan

"Bicolour Veil Nebula" by Peter Feltoti.Credit: Peter Feltoti

"The Soul of Space (Close-up of the Soul Nebula)" by Kush Chandari (who is 13!).Credit: Kush Chandari

"Dolphin Head Nebula" by Yovin YahathugodaCredit: Yovin Yahathugoda

"Flame Nebula" by Steven-Mohr.Credit: Steven Mohr

"NGC 6188 SHOrgb" by Cielaustral team Jean-Claude Canonne, Didier Chaplain, Georges Chassaigne, Philippe Bernhard, Laurent Bourgon, and Nicolas Outters.Credit: Cielaustral team

"Sunspot Looking Out Into Space" by Siu Fone Tang.Credit: Siu Fone Tang

"Star Fall" by Wang Zheng.Credit: Wang Zheng

"The Cave" by Markus van Hauten.Credit: Markus van Hauten

"The Star Observer" by Antoni Cladera Barcelo.Credit: Antoni Cladera Barcelo

"NGC 6723, NGC 6726, NGC 6727 and NGC 6729 Dark Molecular Cloud in Corona Australis" by Steven MohrCredit: Steven Mohr

"The Milky Way on the Ancient Village by Zhang Xiao.Credit: Zhang Xiao

"Star Watcher" by Yang Sutie.Credit: Yang Sutie

"Pleiades Sisters" by Jashanpreet Singh Dingra.Credit: Jashanpreet Singh Dingra

"The Exceptionally Active Ion Tail of Comet-2020F8-SWAN" by Gerald Rhemann.Credit: Gerald Rhemann

"Waterfall" by Anna Dobrovolskaya-Mints.Credit: Anna Dobrovolskaya-Mints

"Glory of Damavand and Milky-Way" by Masoud GhadiriCredit: Masoud Ghadiri

"Chateau de Chambord" by Benjamin Barakat.Credit: Benjamin Barakat

"Dugi Otok - Variant A" by Ivan Vucetic.Credit: Ivan Vucetic

"The Tumult of the Sun" by Hassan Hatami.Credit: Hassan Hatami

"The Rose" by Josep Drudis.Credit: Josep Drudis

"The Magnetic Field of our Active Sun" by Andrew McCarthy.Credit: Andrew McCarthy

"Sunrise of the Magic City" by Jiajun Hua.Credit: Jiajun Hua

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25 ethereal astronomy photos that literally light up the skies - Mashable

Waterfall by Anna Dobrovolskaya-Mints (Israel)This waterfall is in the middle of nowhere in Lapland, but the closest city is Arvidsjaur. It was very cold and while the photographer was waiting for the aurora to start, she put the camera outside to capture the star trails. The last few frames caught the start of Northern Lights and the photographer decided to merge all the frames and got this exceptional result.

Exceptional images of the stars are on full display at the Royal Observatory Greenwich announced its shortlist for the thirteenth Astronomy Photographer of the Year contest. From the Northern Lights reflecting in the waters of remote Sweden to incredible views of spiral galaxies, the finalist images are an inspiring view into the world of astronomy.

While the overall winner, which will be announced in mid-September, will take home a 10,000 cash prize, there are many other categories that will also be rewarded. This includes Aurorae, People and Space, Our Sun, and Galaxies. There is also the Young Astronomy Photographer of the Year, which will be awarded to a talented photographer under the age of 16.

A quick scroll through some of the shortlist shows just how much there is to see and explore within our universe. Some images are clearly rooted on Earth, while others, like Damian Peach's portrait of Saturn, bring us far into the solar system. The finalists hail from around the globe and include familiar names like Andrew McCarthy, who is known for his impressive backyard astrophotography.

Chteau de Chambord by Benjamin Barakat (UK)This magnificent chteau in Chambord, Centre-Val de Loire, France was an amazing location chosen by the photographers best friend and mentor Ralf Rohner, but it proved to be a challenging one as the castle had intervals of illumination with a minutes pause every 15 minutes. During the pauses, the photographer shot away trying to get as many images as possible and while processing it he had to try to mimic the reflection due to the time delay caused by the castle lights.

The Soul of Space (Close-up of the Soul Nebula) by Kush Chandaria (UK), aged 13The Soul Nebula is one of those incredible targets that no matter where you point your telescope, there are always some incredible structures and details to be uncovered. This was the case with this image. With 14 hours of exposure, faint details and structures deep within the nebula began to emerge. The photographer chose to use narrowband filters to image this target and created a Hubble Palette composite.

Saturn at its Best by Damian Peach (UK)In this image, Saturn is shown near its best for 2020, displaying a wealth of details across the globe and ring system. The famous polar hexagon can be seen around the pole at bottom, while many other belts and zones are seen across the planet. The famous Cassini and Encke divisions dominate the view of the rings.

Star Watcher by Yang Sutie (China)As the photographer was driving on the mountain road late at night and turned the corner, he saw a mound on the right side of the road. The mountains lined up and the Milky Way was lined-up in front of the photographer, so he stopped and climbed up the side of the road, set the camera to shoot automatically, and then drove back and forth in this curve. Then he climbed up the hillside and integrated himself into the picture.

The Magnetic Field of our Active Sun by Andrew McCarthy (USA)This image shows how the magnetic field of the Sun pulls up portions of the chromosphere following a large solar flare, with the magnetic field lines on crystal clear display along the limb in hydrogen-alpha light. This also happened while a particularly large active region was along the face of the solar disc. This was captured in black and white and processed partially inverted to highlight the contrast on the surface as well as the atmospheric features on the limb, presented in false color for the aesthetic. This was one of the most interesting features on the Sun in all of 2020 and represents the first major activity since the start of the new solar cycle. The photographer is pleased with the way the processing shows the nature of the Sun in a naturally blue sky while preserving close to the proper hydrogen-alpha tones.

NGC 2024 Flame Nebula by Steven Mohr (Australia)The Flame Nebula, designated as NGC 2024 and Sh2-277, is an emission nebula in the constellation Orion, lying some 900 to 1,500 light-years away from Earth. The bright star Alnitak (just outside the field of view at the top of this image), the easternmost star in the Belt of Orion, shines energetic ultraviolet light into the Flame and this knocks electrons away from the great clouds of hydrogen gas that reside there. Much of the glow results when the electrons and ionized hydrogen recombine. Additional dark gas and dust lies in front of the bright part of the nebula, and this is what causes the dark network that appears in the centre of the glowing gas. The Flame Nebula is part of the Orion Molecular Cloud Complex, a star-forming region that includes the famous Horsehead Nebula.

Pleiades Sisters by Jashanpreet Singh Dingra (India), aged 14This is an outstanding image of shining stars over the photographers region in winter. The Pleiades, also known as the Seven Sisters and Messier 45, is an open star cluster containing middle-aged, hot B-type stars in the north-west of the constellation Taurus. It is the nearest star cluster and Messier object to Earth and it is the cluster most obvious to the naked eye in the night sky. The data of this image was processed in Deep Sky Stacker, Photoshop CC 17 and Gimps.

The Star Observer by Antoni Cladera Barcel (Spain).Menorca was declared a Biosphere Reserve by UNESCO in 1993 and credited as a Starlight Reserve in 2019. The photographer captured this image at this natural stone bridge shaped by water erosion. A watchman stands vigilant under the stars as the Milky Way is vertical above the natural arch. To add a soft and warm tone to the arch, the photographer used the light pollution from Mallorca, the neighboring island. The photographer wanted to humanize the landscape and incorporate the human element in the composition to prove that we are just natures guests.

The Milky Way on the Ancient Village by Zhang Xiao (China).Hongcun, an ancient village at the foot of Huangshan Mountain in China, has a history of more than 900 years and in 2000 it became a UNESCO World Heritage Site. Its existing buildings have the unique characteristics of Hui Style Architecture from the Ming and Qing Dynasties. A galaxy of stars fell on the famous Yuezhao Lake surrounded by ancient buildings. This photo was taken after 1a.m., the streetlights in the village had gone out, and no one was around.

Dugi Otok Variant A by Ivan Vucetic (Croatia)The photograph shows a captivating star trail over Dugi Otok in Croatia and the extraordinary relationship between our Planet and the Universe in a way that the human eye cannot perceive it. The photographer intended to capture the reflection of the stars on the water together with the sky, however during the long exposure time that was necessary for star trails the wind increased and seeing conditions were not favorable enough for a clear reflection of the stars. The photographer had to use the stars from the sky in post-processing to achieve the final result.

NGC 3981 by Bernard Miller (USA)This is an image of NGC 3981. It is a spiral galaxy about 65 million light years away in the constellation Crater. Its windswept look is due to its outer arms being stripped away by an interaction with another galaxy. The galaxy is part of the NGC 4038 group, which also contains the well-known interacting Antennae Galaxies. This group is part of the larger Crater Cloud, which is itself a smaller component of the Virgo Supercluster.

NGC 2024 Flame Nebula by Steven Mohr (Australia)The Flame Nebula, designated as NGC 2024 and Sh2-277, is an emission nebula in the constellation Orion, lying some 900 to 1,500 light-years away from Earth. The bright star Alnitak (just outside the field of view at the top of this image), the easternmost star in the Belt of Orion, shines energetic ultraviolet light into the Flame and this knocks electrons away from the great clouds of hydrogen gas that reside there. Much of the glow results when the electrons and ionized hydrogen recombine. Additional dark gas and dust lies in front of the bright part of the nebula, and this is what causes the dark network that appears in the centre of the glowing gas. The Flame Nebula is part of the Orion Molecular Cloud Complex, a star-forming region that includes the famous Horsehead Nebula.

Sunspot Looking out into Space by Siu Fone Tang (USA)This image shows a close-up of a sunspot and the plasma as it flickers and follows the magnetic lines generated by the Sun. The photo depicts what is called the chromosphere, this is imaged using a hydrogen-alpha filter. The photo is made up of multiple frames that are stacked together and then later enhanced using Photoshop. It is an inverted view which creates more contrast.

Sunrise of the Magic City by Jiajun Hua (China)Shanghai is one of the most economically developed cities in China. The photo is taken 16 kilometers away from Lujiazui financial district. Every year there are only a few weeks when photographers can capture the scene of the Sun rising the Central Business District (CBD). The photographer waited for a few days and finally witnessed the Sun rising from the most prosperous area of Shanghai on a heavily polluted morning. The photo is composed of four different exposures from the same perspective, recording the process of the Sun rising.

Iceland Vortex by Larryn Rae (New Zealand)This is a 250 panorama of the Aurora Borealis in Iceland. The photographer came across this estuary that reflected the sky perfectly on a well below freezing winters night, and captured the panorama first, and then took a shot of himself out on the ice. For the photographer this is one of the most amazing aurora images that he has ever captured, and it sums up an awe-inspiring trip to Iceland in wintertime that also emphasized the feeling of being just a tiny part of the planets existence in the face of a very powerful natural environment. The panorama is comprised of twenty images, two rows of ten, captured on a Canon 5DMk3 and Canon 16-35mm.

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Incredible Finalists of the 2021 Astronomy Photographer of the Year - My Modern Met

The universe comes off as a vast and immeasurable entity whose depths are imperceptible to Earthlings. But in the pursuit of simplifying all that surrounds us, scientists have made great strides in understanding the space we inhabit.

Now, Japanese astronomers have developed an astounding technique to measure the universe. Using artificial intelligence, scientists were able to remove noise in astronomical data which iscaused by random variations in the shapes of galaxies.

What did the scientists do?

Scientists used supercomputer simulations and tested large mock data before performing the same on real data from space. After extensive testing, scientists used the tool on data derived from Japans Subaru Telescope.

To their surprise, it worked! The results that followed remained largely in sync withthe currently accepted models of the universe. If employed on a bigger scale, the tool could help scientists analyse expansive data from astronomical surveys.

Current methods cannot effectively get rid of the noise which pervades all data from space. To avoid interference from noise data, the team used the worlds most advanced astronomy supercomputer called ATERUI II.

Using real data from the Subaru Telescope, they generated 25,000 mock galaxy catalogues.

Also read:Explosion on Sun equivalent to millions of hydrogen bombs causes biggest solar flare in 4 years

What's causing data distortion?

All data from space can be distorted by the gravity of whats in the foreground eclipsing its background. This is called gravitational lensing. Measurements of such lensing is used to better understand the universe. Essentially, a galaxy directly visible to us could be manipulating data about what lies behind it.

But its difficult to differentiate oddly-looking galaxies from distorting ones that manipulate data. Its called shape noise and regularly gets in the way of understanding the universe.

Based on these understandings, scientists added noise to the artificial data sets and trained AI to recover lensing data from the mock data. The AI was able to highlight previously unobservable details from this data.

Building on this, scientists used the AI model on the real world, covering 21 square degrees of the sky. They found that the details registered about the foreground were actually consistent with existing knowledge about the cosmos.

Also read:'Orphan cloud' bigger than Milky Way found in 'no-galaxy's land' by scientists

The research was published in the April issueof Monthly Notices of the Royal Astronomical Society.

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Astronomers use artificial intelligence to reveal the true shape of universe - WION

In the scheme of galactic magic tricks, one of the more difficult is making an entire star disappear. Especially with the added difficulty of making it reappear again a little over six months later.

Yet this is apparently what happened to a star halfway across the galaxy from us. In 2012, the star slowly faded over a few months, dropping in brightness by an astonishing 97% (that that, Betelgeuse!) before rising again at the same rate it faded. A drop like that is extremely weird, and very difficult to explain.

In fact, it's not clear what caused it. Astronomers studying it think they have an idea a giant disk of dust blocking the star from our view but it doesn't explain everything. So this trick is still something of a mystery.

The star is called VVV-WIT-08, and that name itself is worth a moment to explain. It was found in a project called the VISTA Variables in Via Lactea where VISTA stands for the Visible and Infrared Survey Telescope for Astronomy, Variables means stars that change brightness, and Via Lactea is the original Latin term for, literally, Milky Way. This is a survey that looked toward the galactic center, observing hundreds of millions of stars (!!) to measure their brightness over a period of several years.

When you look at that many stars, most will be well behaved and understood, young ones, middle-aged ones like the Sun, dead or dying ones, and so on. But with such a huge number, some are going to act weird. Astronomers kept a list of objects they didn't understand, which they called the "What is this?" list WIT.

So yup. VVV-WIT-08 is the eighth star on their list. Others included bizarre objects that may be stars that have collided, a distant galaxy that changed in brightness, and more.

The star in this case is a bit strange all by itself. It's clearly a big star, and cooler than the Sun, which means it probably started out life very much like the Sun but is now dying. Stars like that expand hugely and their temperature drops, so we call them red giants. VVV-WIT-08 is probably something like 100 million kilometers across wide enough that if you replaced the Sun with it, the star would engulf Mercury.

That's actually a bit smaller than you'd expect for a star like this, which is odd. Also, when they measured how fast it was moving through space, it was hauling gas, moving at nearly 500 kilometers per second. The distance to the star isn't well constrained, but it's likely a part of what's called the bulge, the roughly spherical cloud of stars surrounding the center of the Milky Way. Some stars in the bulge do move that rapidly, but one way of measuring its distance puts it well on the other side of the bulge from us, which in turn means its moving so rapidly it might escape from the galaxy entirely! But that distance measurement relies on knowing what kind of star it is, and if it's not a giant (but, say, on its way to becoming one, what we call a subgiant) then maybe it's closer than that measurement indicates, and indeed part of the bulge.

The point being the star is weird without suddenly dropping to 3% of its normal brightness over the course of a few months.

What could do that?

The obvious idea is that something blocked its light. Some stars do brighten and dim, but not by that huge amount. So this is more likely some external object getting in the way. The astronomers who looked at the data first assumed it was a dust cloud between us and it, but the odds of that happening in this way are extremely small, so they rule that out.

Their next idea is that there's something orbiting the star itself blocking its light. Looking at the data carefully and running various models to see what works best to explain the observations, what they found is no less astonishing than the star itself: It must have a companion star orbiting it, and surrounding that star is a vast disk of opaque dust, at least as wide as the giant star itself and possibly much larger.

We see this circular disk at an angle, so it looks like an ellipse (like the circular the rim of a drinking glass seen at an angle). The narrow diameter of the ellipse is something like 100 million kilometers, then, and the long axis may be much larger. It's also possible we're seeing it nearly edge-on, in which case it's the thickness of the disk that's the size of the giant star. Either way, it's a big disk.

So what then is the companion star? That's not clear. Middle-aged stars like the Sun can have disks but they tend to be thin; the fact that the disk blocked nearly all the star's light indicates the observed disk is thick and opaque. White dwarfs (dead cinders of stars once like the Sun) can have thick disks, but they're too small to explain what was seen with VVV-WIT-08. Other kinds of stars have similar issues.

One idea that fits well is that the companion star stripped material from the giant via gravity. This sort of mass transfer is common, and would explain why the giant is smaller than expected. However, given the length of time of the eclipse (200 days) and the fact that is was only seen once and never repeated, the companion star would have to orbit the giant at a decent distance, too far for mass transfer to occur. Maybe they started closer, but as the material moved from one star to the other a lot of the mass was lost to space; this would decrease the stars' mutual gravity, and they'd separate.

So yeah, as you can see, there's no simple explanation here. Everything has lots of steps, weird circumstances, and difficult to overcome obstacles.

Surprisingly, other stars like this are known. Epsilon Aurigae, a star visible in the northeast in winter, also undergoes eclipses by a dust disk surrounding companion stars, though the system details are different. And the astronomers found two more stars (VVV-WIT-10 and 11) that behave in a similar fashion to 08. So it's weird and rare but not necessarily one of a kind.

Astronomy is a peculiar science. We look at a dot in the sky, one of billions, and over time see it change. And from that meager data we get dying stars, binary stars, stars encircled by huge dark disks, stars racing through space at high speeds and sometimes all of those at once. It's quite the result from such a small effort.

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What caused an old, giant star to disappear for over half a year? - SYFY WIRE

The U.S. National Science Foundation commissioned a study by the independent science advisory group JASON to assess the impact of current and planned large satellite constellations on astronomical observations in 2020. The charge for JASON was to:

NSF commissioned the report as a resource for all stakeholders. The JASON group had broad discretion in constructing its report and identifying relevant issues. The report sets benchmarks and the foundation for discussing the impacts on astronomy at various wavelengths.

NSF is reviewing the report's findings and recommendations and intends to continue to work with stakeholders on the development of mutual solutions.

Please review the full PDF report.

Recent and upcoming relevant activities and events can be found at the following:

FOR ADDITIONAL INFORMATION

For questions related to the report contents, contact Mitre Corporation at glong@mitre.org. For questions related to NSF's astronomy program, contact mpscomms@nsf.gov.

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Jason Report on the Impacts of Large Satellite Constellations - National Science Foundation

GREEN BANK, W.Va. (WOWK) Astronomers at the National Science Foundations Green Bank Telescope (GBT) in West Virginia discovered a massive, previously-unknown structure in the Milky Way galaxy, according to a paper published in The Astrophysical Journal in mid-June.

The first discovery happened with a smaller telescope but researchers had to bring in a larger, 20-meter telescope to confirm the unexpected observation.

Sometimes, in our galaxy, not everything is visible to the naked eye and thats what is happening here. This discovery was made using radio spectrum. Essentially, the astronomers are able to see things with the worlds largest fully steerable radio telescope, which looks like a large dish. Since the GBT has a high level of sensitivity, it was able to detect this extremely large structure thats made up of molecular gas, versus a physical moon or planet. Right now, the people doing the research believe the structure extends far into the distant parts of the Milky Way galaxy.

To be even more sure, we tried several different independent signal processing techniques on the GBT and 20-meter results to attempt to remove the feature as if it were from the instrumental background, rather than a real signal, and none of these methods managed to remove it, said researcher Philip Engelke.

The researchers went through another exhaustive 100 hours of observations at many different points across parts of the galaxy and found that it has a similar shape and extent of other components known about within the galactic structure. These observations had proven, the accidental finding was a real thing.

According to the GBT staff, the existence of this massive structure has implications for star formation theories, as well as the structure, make-up, and total mass of the interstellar medium.

The find dates back to 2012, when astronomer Ron Allen, a professor with the Physics and Astronomy Department of Johns Hopkins University, stumbled across emissions that led to the discovery.

However, Allen died in August 2020, just as his research was being drafted. So his former PhD students stepped in and finished the work for publication in the Astrophysical Journal.

Michael Busch said, Ron was an incredible mentor, a brilliant astronomer, and a great friend to me I will miss him dearly. Engelke added, who completed his doctorate in 2019, We were very lucky to have known him. Ron was truly excited about this discovery, and I know he would have been proud of the result. Michael and I look forward to continued research inspired by this discovery.

To learn more about Green Bank Observatory science and to see research opportunities visit their website.

The Green Bank Observatory is a facility of the National Science Foundation and is operated by Associated Universities, Inc.

The Green Bank Observatory has more on the technical aspects of this massive structure:

The Universe is composed of a mysterious interstellar medium, which scientists are still learning more about. The major componentof the molecular gas in the interstellar medium is H2, but the H2 is usually undetectable! To map it out, radio astronomers look for tracers in the form of signals from other molecules mixed with the H2 in smaller quantities, and the standard tracer is carbon monoxide (CO). However, depending on how diffuse and cold the H2 and CO gases are, they still might not be seen. In 2005, astronomers (Grenier et al.) found an excess of cosmic rays, of unknown origin, emanating from the disk of our Galaxy. Was it possible that these rays were a clue to large reserves of molecular gas not yet been detected, and was there another method to trace this gas and confirm its existence?

In 2012, astronomerRon Allen, a professor with thePhysics and Astronomy Department of Johns Hopkins University, unexpectedlyfound OH emission without corresponding CO emission while working on an unrelated project. As OHisalsoa gas molecule that occurs in clouds of molecularH2, thisfinding hintedthat theremight bean abundant portion of H2 not traced by CO, also referred to as CO-dark molecular gas.

Allen worked with Dave Hogg of National Radio Astronomy Observatory to create a new research program using the GBTto observeOH as an alternative tracer of H2.Philip Engelke, a new Ph.D. studentat Johns Hopkins University, joined the project soon after. In 2015, the first results of this research were published, showing that OHindeedtraces the CO-Dark component of H2remarkably well. While it required long exposure times, the OH observations began filling in the gaps between previous CO observations, showing molecular gas as a major component in the structure of our Galaxy.

Later in 2015, while reviewing data, Engelkenoticed a bump-likefeature, whichhe initiallythought corresponded to the Outer Arm of our Milky Way Galaxy.Follow-up observations revealed a large, faint, broad feature in the entire line of sight.Allenand team were intrigued, but suspected thatthis feature could bean instrumentalby-product of the GBT itself, rather than an actual feature in the Galaxy. The researchers came up with a test: observe the feature with a completely independent telescope.

In 2018, 100 hours of independent observations were conducted using the Observatorys 20-meter Telescope. Johns Hopkins PhD student Michael Busch joined Allens team and played a major role in this work. The 20-meter, a much smaller and older instrument, is primarily used in educational projects including the University of North Carolinas SkyNet.

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Astronomers accidentally discover massive galactic structure with Green Bank Telescope - KRON4