Category Archives: Astronomy

The ingredients for life are spread throughout the universe. While Earth is the only known place in the universe with life, detecting life beyond Earth is a major goal of modern astronomy and planetary science.

We are two scientists who study exoplanets and astrobiology. Thanks in large part to next-generation telescopes like Webb, researchers like us will soon be able to measure the chemical makeup of atmospheres of planets around other stars. The hope is that one or more of these planets will have a chemical signature of life.

Life might exist in the Solar System where there is liquid water like the subsurface aquifers on Mars or in the oceans of Jupiters moon Europa. However, searching for life in these places is incredibly difficult, as they are hard to reach, and detecting life would require sending a probe to return physical samples.

Many astronomers believe theres a good chance that life exists on planets orbiting other stars, and its possible thats where life will first be found.

Theoretical calculations suggest that there are around 300 million potentially habitable planets in the Milky Way galaxy alone and several habitable Earth-sized planets within only 30 light-years of Earth essentially humanitys galactic neighbors. So far, astronomers have discovered over 5,000 exoplanets, including hundreds of potentially habitable ones, using indirect methods that measure how a planet affects its nearby star. These measurements can give astronomers information on the mass and size of an exoplanet, but not much else.

To detect life on a distant planet, astrobiologists will study starlight that has interacted with a planets surface or atmosphere. If the atmosphere or surface was transformed by life, the light might carry a clue called a biosignature.

For the first half of its existence, Earth sported an atmosphere without oxygen, even though it hosted simple, single-celled life. Earths biosignature was very faint during this early era.

That changed abruptly 2.4 billion years ago when a new family of algae evolved. The algae used a process of photosynthesis that produces free oxygen oxygen that isnt chemically bonded to any other element. From that time on, Earths oxygen-filled atmosphere has left a strong and easily detectable biosignature on the light that passes through it.

When light bounces off the surface of a material or passes through a gas, certain wavelengths of the light are more likely to remain trapped in the gas or materials surface than others. This selective trapping of wavelengths of light is why objects are different colors. Leaves are green because chlorophyll is particularly good at absorbing light in the red and blue wavelengths. As light hits a leaf, the red and blue wavelengths are absorbed, leaving mostly green light to bounce back into your eyes.

The pattern of missing light is determined by the specific composition of the material the light interacts with. Because of this, astronomers can learn something about the composition of an exoplanets atmosphere or surface by, in essence, measuring the specific color of light that comes from a planet.

This method can be used to recognize the presence of certain atmospheric gases that are associated with life such as oxygen or methane because these gasses leave very specific signatures in light. It could also be used to detect peculiar colors on the surface of a planet.

On Earth, for example, the chlorophyll and other pigments plants and algae use for photosynthesis capture specific wavelengths of light. These pigments produce characteristic colors that can be detected by using a sensitive infrared camera. If you were to see this color reflecting off the surface of a distant planet, it would potentially signify the presence of chlorophyll.

It takes an incredibly powerful telescope to detect these subtle changes to the light coming from a potentially habitable exoplanet. For now, the only telescope capable of such a feat is the new James Webb Space Telescope. As it began science operations in July 2022, Webb took a reading of the spectrum of the gas giant exoplanet WASP-96b. The spectrum showed the presence of water and clouds, but a planet as large and hot as WASP-96b is unlikely to host life.

However, this early data shows that Webb is capable of detecting faint chemical signatures in the light coming from exoplanets. In the coming months, Webb is set to turn its mirrors toward TRAPPIST-1e, a potentially habitable Earth-sized planet a mere 39 light-years from Earth.

Webb can look for biosignatures by studying planets as they pass in front of their host stars and capturing starlight that filters through the planets atmosphere. But Webb was not designed to search for life, so the telescope is only able to scrutinize a few of the nearest potentially habitable worlds. It also can only detect changes to atmospheric levels of carbon dioxide, methane, and water vapor. While certain combinations of these gasses may suggest life, Webb is not able to detect the presence of unbonded oxygen, which is the strongest signal for life.

Leading concepts for future, even more, powerful space telescopes include plans to block the bright light of a planets host star to reveal starlight reflected back from the planet. This idea is similar to using your hand to block sunlight to better see something in the distance. Future space telescopes could use small, internal masks or large, external, umbrella-like spacecraft to do this. Once the starlight is blocked, it becomes much easier to study light bouncing off a planet.

There are also three enormous, ground-based telescopes currently under construction that will be able to search for biosignatures: the Giant Magellen Telescope, the Thirty Meter Telescope, and the European Extremely Large Telescope. Each is far more powerful than existing telescopes on Earth, and despite the handicap of Earths atmosphere distorting starlight, these telescopes might be able to probe the atmospheres of the closest worlds for oxygen.

Even using the most powerful telescopes of the coming decades, astrobiologists will only be able to detect strong biosignatures produced by worlds that have been completely transformed by life.

Unfortunately, most gases released by terrestrial life can also be produced by nonbiological processes cows and volcanoes both release methane. Photosynthesis produces oxygen, but sunlight does, too, when it splits water molecules into oxygen and hydrogen. There is a good chance astronomers will detect some false positives when looking for distant life. To help rule out false positives, astronomers will need to understand a planet of interest well enough to understand whether its geologic or atmospheric processes could mimic a biosignature.

The next generation of exoplanet studies has the potential to pass the bar of the extraordinary evidence needed to prove the existence of life. The first data release from the James Webb Space Telescope gives us a sense of the exciting progress thats coming soon.

This article was originally published on The Conversation by Chris Impey and Daniel Apai at the University of Arizona. Read the original article here.

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The best ways to find life using the Webb telescope, according to two astronomers - Inverse

There is a massive monster lurking at the beginning of the universe, 10 billion times the mass of our Sun. And one of the James Webb Space Telescopes (JWST) first tasks will be piercing through the shroud of incredible distance and time to help astronomers determine if it is what it seems to be: a supermassive black hole, one out of a handful of the largest yet found, from the earliest moments of star formation.

The search, part of JWSTs first cycle of observations, is being led by Jinyi Yang, an astronomer and the Peter Strittmatter Fellow at the University of Arizonas Steward Observatory. Her team will be one of the first to use the new instruments available on JWST to observe the formation of a quasar the ultra-bright core of a galactic nucleus with a supermassive black hole at its center in the epoch where stars and galaxies were only just beginning to form.

WHATS NEW As JWST has begun to release its first images to the public, this is one of the Cycle 1 General Observers (or GO) targets. Over the next year, 6000 hours of the new space telescopes time will be spent on projects selected from proposals from astronomers and physicists from around the world 286 projects were selected out of over 1000 proposals from 44 countries, and the majority are relatively short, like this proposal. The total time Webb will spend on these measurements is less than six hours, but the gains will be like nothing astronomers have seen before.

Speaking with Inverse, Yang noted that the sensitivity and resolution of the Webb telescopes Near Infrared Spectrograph (or NIRSpec) means that astronomers will be able to see what we have never seen. The ability to get high-resolution data from spectra in the mid-infrared wavelengths (30-50 micrometers) will allow astronomers to catch a glimpse of a monster black hole from the very beginning of the formation of stars, galaxies, and black holes.

An illustration of a quasar.Shutterstock

WHY IT MATTERS The quasar that Webb will target for this research, J0038-0653, is one of the very oldest that we know about. Its infrared waves are from the first 800 million years of the universes existence, and the inflation of the universe means it has been traveling 13 billion years to reach us. Because of this vast distance, even the most powerful instruments could do little more than confirm its existence. In fact, the first quasars from this early in the formation of stars, galaxies, and black holes were only found a little over a decade ago, a discover Yang credits with the direction of her career.

Because it is so old, the quasar is moving away from Earth that it appears in such high redshift that it can only be observed at high resolution with instruments that can cover the mid-infrared spectrum. Webbs NIRSpec will be able to observe a tiny slice of sky to measure the mass of the supermassive black hole within the quasar. Right now, astronomers only have a general sense of the mass of the black holes mass.

Having a much more precise measurement would help to clarify how black holes began to grow in the early universe. If the James Webb Space Telescope can confirm this quasar really is this massive, it would mean that early black holes were especially massiveor grew much more quickly than their modern counterparts.

Dr. Yang also notes that because high-redshift quasars like this one are so bright and so distant, observations of them and their spectra provide direct information about the state of the intergalactic mediumthe extremely diffuse plasma that isnt gathered into galaxiesas galaxies formed. The quasars illuminate the process by which the earliest galaxies formed during the epoch of reionization.

WHATS NEXT Right now, GO projects like this one are going to be using a little over half the James Webb Space Telescopes time over the next year as the program begins to work through its first observation objectives. Right now, this is one of 29 small projects focusing on supermassive black holes and other active galactic nuclei, which Dr. Yang notes are going to start a whole new generation in astronomy. But for the time being, she adds, its a little nervous to wait for the data but very exciting.

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This behemoth black hole got too big too early the Webb Telescope could find out why - Inverse

Title: Audio Description And Other Inclusive Resources In The Outreach Project Astroaccesible

Authors: Enrique Prez-Montero, Celia Barns-Castao, Emilio Garca Lpez-Caro

First Authors Institution: Instituto de Astrofsica de Andaluca CSIC, Glorieta de la Astronoma s/n, 18008, Granada, Spain

Status: To appear in 2nd Workshop on Astronomy Beyond the Common Senses (2022) RevMexAA(SC) [closed access]

Most people see astronomy as a purely visual fieldliterally. Scientists observe planets or galaxies with a telescope, create colorful images, analyze plotted data, or study stars whizzing about in simulations. A group led by Dr. Enrique Prez Montero, a scientist at the Institute of Astrophysics of Andalusia in Spain, is trying to change this solely visual picture. Dr. Prez Montero uses spectroscopy to study the interplay between massive stars and the interstellar medium, along with looking at surveys of star-forming galaxies. He is also visually impaired, and leads the project Astroaccessible, which aims to let blind and visually impaired (BVI) individuals experience and participate in astronomy through conferences, classes, and accessible resources that can help level the playing field between sighted and blind individuals.

While in-person outreach events are best-suited for introducing valuable resources such as high-contrast images, 3D printed sky maps, or hands-on models, the pandemic has pushed these kinds of opportunities into the virtual world of Zoom. Without specialized equipment, participants are no longer easily able to access these kinds of tactile resources. Astroaccessibles project El Universo en palabras (The Universe in words) overcomes this barrier by instead letting participants hear the universe when touching it isnt an option.

The projects main goal is to create audio descriptions (AD) of images featuring various well-known and popular astronomical objects, such as the Crab Nebula and Whirlpool Galaxy. Audio description isnt a new conceptits been around since the 1990s, and nowadays many streaming services like Netflix offer audio description for a selection of programming. For a movie or TV show, turning on AD adds extra narration in between dialogue that explains important visual elements on screen, such as how a character is moving or the arrangement of a room. While initially created to make audiovisual media more accessible to a BVI audience, AD can create a richer, more helpful experience for other users such as viewers who have trouble understanding emotion in facial expression, or a sighted viewer that might have missed an important background detail during a chaotic action scene.

Audio description also doesnt have to be limited to TV shows or movies. The Astroaccessible team points out past studies that have found that AD in museums and live events have the potential to give every visitor an enriching experience. If youre at an art or history museum, it might be overwhelming to look at a large, detailed painting all at once or figure out what parts of an ancient machine are used for. Having a guided audio description of where to look gives visitors a multisensory experience while also pointing out details they might not have noticed on their own, thereby giving them a more complete understanding and appreciation of the painting or artifact they are examining.

El Universo en palabras aims to create the same experience for viewers learning about the cosmos. Translation and Interpreting students working with both AD and astronomy outreach experts at the University of Granada took on the challenge of translating the visual details of complex deep-space objects into an audible, detailed description that is heard over a video showcasing each object. The astronomical image is not stagnantthe video pans around and zooms in and out, highlighting different parts of the object while describing its structure, color, and details, explaining the scientific significance of these features as well. This format provides a mental conception of the object and a helpful guide for interpreting what you are seeingan audio tour breaking down each galaxys or nebulas complex structure into bite-sized pieces. Students can also use these videos in parallel with any tactile resources that might be available, as well as with sonifications of these objects made by other outreach groups such as the nebulous Pillars of Creation or gas of the galaxy M87, host to the first-ever imaged black hole. The group has currently produced five videos of various Messier objects and aim to create many more in the future, hopefully also translated into other languages.

The majority of sighted astronomers cant don space suits and fly through a nebula or star hop around a galaxy to learn about the universe. Instead, they use tools available to them to gather remote data and convert it into the medium thats most natural to thema picture or a graph. But groups like Astroaccessible show us that we dont have to limit ourselves to displaying data this wayvisuals shown in tandem with audio and tactile media can create a delightful accessible experience for everyone, no matter if you prefer to put your eye or ear to the cosmos.

Astrobite edited by Olivia Cooper

Featured image credit: Astroaccessible

About Katya GozmanHi! Im a third year PhD candidate at the University of Michigan. Im originally from the Northwest suburbs of Chicago and did my undergrad at the University of Chicago. There, my research primarily focused on gravitational lensing and galaxies while also dabbling in machine learning and neural networks. Nowadays Im working on galaxy mergers and stellar halos, currently studying the spiral galaxy M94. I love doing astronomy outreach and frequently volunteer with a STEAM education non-profit in Wisconsin called Geneva Lake Astrophysics and STEAM, as well as work at our on-campus observatory and planetarium.

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The Universe, One Word at a Time - Astrobites

The Milky Way is coming! This month, we will say goodbye to the galaxies near Leo the Lion because, as the earth moves along its orbit, the earth faces in the direction of the Milky Way. There are still lots of galaxies to be seen, but they are a challenge to find and it will take a big 'scope, 10 inches or bigger, to see them well.

Our galaxy is a so-called barred spiral. Look up barred spirals and you will see good examples and good illustrations.

In the spiral arms of our galaxy, there is still star formation -- new stars just starting their fusion cycle and moving toward maturity. One definite sign of this is that there are very many ambient clouds of hydrogen, collapsing over time to form new stars.

In this article, I have included a good example, lying along a line of sight toward the center of our galaxy. This example is the Lagoon Nebula, a rich star-forming region about 4,000 to 6,000 lightyears away. Such areas of hydrogen fluoresce in a characteristic red or magenta color because the forming stars, young and hot, give off ultraviolet radiation very strongly and this causes the characteristic glow. It is the same mechanism as occurs when one shines a black light, which is really an ultraviolet light our eyes can't see, in a cave with certain minerals. These minerals are stimulated. They glow.

In the image I have provided, some stars have already formed; some stars have yet to form, but they will, over long periods of time. Spiral galaxies are active things -- they change over very long spans of time, mostly by making new stars.

Our Milky Way galaxy has very many of these star-forming regions. In elliptical galaxies, another form of galaxy entirely different from spiral galaxies, the star-forming clouds of hydrogen have all been turned into stars and we do not see the red, glowing areas where there is ambient hydrogen. Lots of good images of elliptical galaxies are available on the Internet.

Summer is the time of the Milky Way. It is also a good time to learn two constellations if you don't already know them. A really large constellation is Scorpio the scorpion. You could look this up on a star map on the Internet and, after you have seen an illustration, try to make it out on the southern horizon. It really does form the shape of a very large scorpion, complete with stars that form its claws and a stinger tail! It also has a very bright and very large red giant star, Antares, to mark the center of the scorpion.

A bit more difficult is the constellation Sagittarius. You can look this one up too, but it will be easier to find in the sky if you look for a teapot instead of the mythological character. Even so, this constellation does not contain any really bright stars and is often just on the edge of the southern horizon from our vantage in Arkansas.

Summer often brings very good weather to look at the Milky Way and this is best done under the darkest sky you can find. Use binoculars to cruise along its edge -- it is very beautiful!

David Cater is a former faculty member of JBU. Email him at [emailprotected] Opinions expressed are those of the author.

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ASTRONOMY: The Milky Way is coming! - NWAOnline

Understanding the effects satellites have on astronomy observations is the focus of a new, collaborative effort between NOAAs Office of Space Commerce (OSC), the American Astronomical Society, the International Astronomical Union and the Satellite Industry Association.

The series will provide opportunities for information sharing on how commercial space companies can preserve astronomical observational data quality and analysis through technological innovations, measurements, best practices and coordination.

This series will serve as a platform for identifying potential conflicts and enable the Department of Commerce to provide information and guidance to new space industry entrants regarding space technology and engineering initiatives. The events will connect commercial space companies of all sizes with the astronomical science and engineering communities.

It will also share information about partnership opportunities for industry for enhancing innovation in the space, astronomical and data sciences, including instrumentation and materials engineering, measurements and calibrations for brightness and orbital and position data architectures.

Richard DalBello, the newly hired OSC director, signed a joint project agreement to collaborate with the Satellite Industry Association, the American Astronomical Society, the International Astronomy Union Center for the Protection of Dark and Quiet Skies, and the National Science Foundation to kick off the Effects of Satellites on Astronomy Symposia series.

DalBello said during the past decade the satellite industry has experienced dramatic growth and that has resulted in a wide array of new technologies and spawned revolutionary new commercial markets. However, this growth has caused new complications for the global astronomy community. Balancing the needs of the commercial satellite industry and the international astronomical community will require the combined efforts of both of these communities, he said.

Note: On June 28, the Commerce Departments National Institute of Standards and Technology (NIST) will host a symposium on how commercial space companies can engage in efforts for preserving astronomical observational data quality and analysis through technological innovations, measurements, best practices, and collaborative coordination among multiple stakeholders.

Office of Space Commerce Director, Richard DalBello, will give opening remarks, and Simonetta Di Pippo, former Director, United Nations Office of Outer Space Affairs, will deliver the morning keynote.

This will be the first symposium in a series of events to connect commercial space companies of all sizes, from start-ups to large enterprises, with the astronomical science and engineering communities.

All commercial and public stakeholders supporting space activities are welcome to participate.

View agenda and register at this direct link

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NOAA's Office of Space Commerce joins an industry focus on the effects of satellites on astronomy SatNews - SatNews

EAC Photo: Eastern Arizona Colleges Discovery Park Campus was honored to share an afternoon of astronomy-based lessons with the Natural Resource Youth Practicum Camp last week. The camp, titled Nowhi ni nlt eego anlsih in Apache, is designed to provide a study of scientific principles and cultural heritage (with perspectives of today), to help mold youth into future leaders.

Contributed Article/Courtesy EAC

ThatcherEastern Arizona Colleges Discovery Park Campus was honored to share an afternoon of astronomy-based lessons with the Natural Resource Youth Practicum Camp last week. The camp, titled Nowhi ni nlt eego anlsih in Apache, is designed to provide a study of scientific principles and cultural heritage (with perspectives of today), to help mold youth into future leaders.

The astronomy lessons shared during the visit included learning about the 20 Tinsley Telescope in the Gov Aker Observatory with guest instructor, John Ratje, retired director of the Mt. Graham International Observatory, member of the Desert SkyGazers Astronomy Club, and telescope operator for the EAC Discovery Park Campus.

Students also viewed an educational video about the Large Binocular Telescope (LBT) the largest and most powerful telescope in the world (located at the Mt. Graham International Observatory on Mt. Graham) and talked about what is in the night skies: stars, planets, and galaxies, with EAC Discovery Park Campus director, Paul Anger.

The final activity included a ride on the Discovery Park Space Shuttle simulator Polaris, operated by Discovery Park Campus secretary, Monica Clarine, where the students were able to virtually visit many of the known planets and moons in our solar system.

These boys and girls were a pleasure to work with, said Anger. They were excited to learn about the hidden world of space and astronomy and had a lot of great questions. We look forward to participating in the Natural Resource Youth Practicum Camps in the future!

For more information on the activities available at EACs Discovery Park Campus, or tour information for the telescopes at the Mount Graham International Observatory, contact EACs Discovery Park Campus at (928) 428-6260 or emaildiscoverypark@eac.edu, or go towww.eac.edu/discoverypark.

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EAC's Discovery Park Campus hosts members of the 2022 San Carlos Nowhi ni' nlt eego anlsih Take Care of Our Land Natural Resource Youth Practicum Camp...

The teams identification of iso-propanol in space was made possible through observations of a particular star-forming region in our galaxy where many molecules have already been detected. Sagittarius B2 is located close to the center of our galaxy and is the target of an extended investigation of its chemical composition with the Atacama Large Millimeter/submillimeter Array telescope in Chile. Microwave-wavelength emission from molecules floating around in Sgr B2 provides spectral patterns that can be recognized back on Earth, but these patterns can be weak and difficult to distinguish from each other. ALMAs introduction 10 years ago has made it possible to go beyond what could be achieved with earlier, single-dish telescope technology.

So far, the teams ALMA observations have led to the identification of three new organic molecules (iso-propyl cyanide, N-methylformamide, urea) since 2014. The ALMA projects latest result is now the detection of propanol (C3H7OH).

Our group began to investigate the chemical composition of Sgr B2 more than 15 years ago, said Arnaud Belloche from the Max Planck Institute for Radio Astronomy, the lead author of the detection paper. These observations were successful and led in particular to the first interstellar detection of several organic molecules, among many other results.

Propanol is an alcohol and is the largest in this class of molecule to be detected in interstellar space. It exists in two forms (isomers), depending on which carbon atom the hydroxyl functional group is attached to: 1) normal propanol, with OH bound to a terminal carbon atom of the chain, and 2) iso-propanol, with the hydroxyl bound to the central carbon atom in the chain. Both isomers of propanol in Sgr B2 were identified in the teams ALMA data set; the first interstellar detection of normal propanol was obtained shortly before the ALMA detection by a Spanish research team with single-dish radio telescopes in a molecular cloud not far from Sgr B2. The detection of iso-propanol toward Sgr B2, however, was only possible with ALMA.

This research is part of a long-standing effort to probe the chemical composition of sites in Sgr B2 where new stars are being formed and understand the chemical processes at work during star formation. The goal is to determine the chemical composition of the star-forming sites, and possibly identify new interstellar molecules. Many of these molecules are formed on the surfaces of microscopic dust grains, where they remain until dust temperatures are high enough to release them.

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UVA Astrochemist Helps Explore the Chemistry of Outer Space - UVA Today

The asteroid Bennu has natural armor against small meteorite impacts: Its covered in Styrofoam-like rubble.

Thats the conclusion drawn by a team of scientists looking at (101955) Bennu, a wee 500-meter-wide near-Earth asteroid that was visited by the OSIRIS-REx spacecraft from 2018 to 2021. Bennu is a rubble pile asteroid; its not a solid monolithic piece of rock but instead a more like a collection of millions of small rocks all held together by their own mutual gravity.

Its thought that rubble pile asteroids may have once been more solid, but when an asteroid chunk gets hit by another asteroid it can shatter into a myriad of pieces which then recollect into the loosely held aggregation. The gravity of a small asteroid like Bennu is incredibly weak youd weigh a fraction of an ounce standing on its surface but its enough to hold it together.

The astronomers looking into Bennu investigated images taken by OSIRIS-REx to look at craters. Impact craters can tell you a lot about an object. In general there are few really big ones, more medium-sized ones, and countless small ones. Thats true, at least, for big, solid objects like planets and moons.

They looked at a total of 1,560 craters on Bennu, and found something very interesting [link to paper]. It does have a few big craters and more medium ones. But then it pulls a switch: There are actually very few small ones. The size distribution of craters turns over around 2-3 meters; in other words the number of them increases as the craters get smaller until they reach a size below 2-3 meters, where they actually become fewer in number.

Why?

Rocks!

The surface of Bennu is covered in, well, rubble. These rocks can be very small, up to boulders many meters across. Importantly, despite looking like the detritus left after a construction project, the rocks on Bennu are not like those on Earth. Theyre very porous and friable crumbly. So much so that the big boulders seen precariously balanced on the surface of the asteroid might collapse under their own weight here on Earth.

For example, OSIRIS-Rex touched down briefly on the surface of Bennu to collect samples. Despite moving at a leisurely 10 centimeters per second normal walking speed is 10 times faster the spacecraft still crushed a 20-cm rock sitting on the surface, showing that the rock was held together basically by a whisper.

Youd think that something that would be crushed by a kitten sitting on it would make terrible armor, but in fact the opposite is true. Small rocks moving through space at high speed make craters when they hit a solid surface as the huge kinetic energy (the energy of motion) is converted into mechanical energy, displacing and ejecting the surface material and digging out a crater. But if the surface is made of crunchy rocks, a lot of the impactors energy goes into crushing those rocks instead of displacing the material to make a crater.

This has major implications both for the science of asteroids and the important task of moving one out of the way should it be headed for Earth. In the latter case, one idea is simply smacking the asteroid hard with a massive space probe, so that the momentum of the probe pushes the asteroid onto a different trajectory. This is the reasoning behind the DART mission, which in October of 2022 will impact the small moon Dimorphos of the slightly larger asteroid Didymos and change its orbit very slightly.

But if the target asteroid is a rubble pile, a lot of the impact energy will go into crushing and shuffling around the surface material instead of moving the asteroid out of the way. So understanding how they behave under impact could actually save the world.

And the science is cool too. For example, looking at the distributions of craters sizes on an asteroid and knowing how much junk is put there in space that can hit it, you can estimate the age of the surface. Over time small craters get erased by smaller impacts, while big ones can last much longer. For Bennu, the scientists estimate craters bigger than 100 meters across can survive for 10 65 million years before being eroded away, while small ones a few meters across can last only a couple of million years tops. It was thought previously those numbers were about 15 times higher, but Bennus natural crumbly armor means the erosion happens much more rapidly.

Like Earth, the surface of Bennu is much younger than the asteroid itself, changing on a cosmically rapid timescale. Its an important step in understanding how asteroids change over time. Beauty may only be skin deep, but on asteroids that skin can make you look way younger than you really are.

There may be more practical benefits to this knowledge, too. Covering a spaceship with porous rubble may not be cost-effective, but a friable layer of material under the ships skin could protect it from smaller micrometeorites. Such a layer has been used in spacesuits for decades. Seeing it in action in a natural environment could give future engineers ideas for upgrades.

And if we do spot a rubble pile on its way toward Earth, there are other ideas besides whacking it you may be dismayed that using a nuke is a good option, though maybe not for the reason you think. Point being that the more we study these asteroids the more likely we can learn how to prevent them from ruining our day and learn some way cool science in the meantime.

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Bad Astronomy | Asteroid Bennu has crumbly rocks that shield it from small impacts | SYFY WIRE - Syfy

When white dwarfs go wild, their planets suffer through the resulting chaos. The evidence shows up later in and around the dying stars atmosphere after it gobbles up planetary and cometary debris. Thats the conclusion a team of UCLA astronomers came to after studying the nearby white dwarf G238-44 in great detail. They found a case of cosmic cannibalism at this dying star, which lies about 86 light-years from Earth.

If that star were in the place of our Sun, it would ingest the remains of planets, asteroids, and comets out to the Kuiper Belt. That expansive buffet makes this stellar cannibalism act one of the most widespread ever seen.

We have never seen both of these kinds of objects accreting onto a white dwarf at the same time, said lead researcher Ted Johnson, a physics and astronomy graduate of UCLA. By studying these white dwarfs, we hope to gain a better understanding of planetary systems that are still intact.

Johnson was part of a team from UCLA, UC San Diego, and the University of Kiel in Germany working to study chemical elements detected in and around the white dwarf atmosphere. They used data from NASAs retired Far Ultraviolet Spectroscopic Explorer, the Keck Observatorys High-Resolution Echelle Spectrometer in Hawaii, and the Hubble Space Telescopes Cosmic Origins Spectrograph and Space Telescope Imaging Spectrograph. The team found and measured the presence of nitrogen, oxygen, magnesium, silicon, and iron, as well as other elements.

The iron is particularly interesting since it makes up the cores of rocky planets like Earth or Mars. Its presence is a clue that terrestrial-type worlds once orbited G238-44. The presence of high amounts of nitrogen implies the system had a pool of icy bodies as well.

As stars like the Sun enter very old age, they leave behind burned-out cores called white dwarfs. Over billions of years, these remnants of dying stars slowly cool down. Before they get to that point, however, the actual death throes can be quite violent and messy. Thats when they cannibalize the worlds around them. The discovery of the leftovers of those planets, comets, and asteroids, in the atmosphere of G238-44 paints an ominous picture of our solar systems future.

We can expect our Sun to go through the process starting in about five billion years. First, it will balloon out to become a red giant, swallowing up planets possibly out to the orbit of Earth. Then, it will lose its outer layers, forming what we call a planetary nebula. Once all thats dissipated to space, whats left is the massive, but tiny white dwarf.

The whole process will tear apart the solar system, ripping planets to shreds and scattering comets and asteroids. Any of those objects that come too close to the white dwarf Sun will get sucked in and destroyed. The scale of the destruction occurs fairly quickly if G238-44s example is any clue. This study shows the shocking scale of the chaos. Within 100 million years after it entered its white dwarf phase, the dying star was able to capture and consume material from its nearby asteroid belt and its far-flung Kuiper beltlike regions.

Not only does this finding show whats in our future, but it also supplies interesting insight into how other systems form. It offers clues to what they contain, and a peek at our own solar systems past. For example, astronomers think that icy objects crashed into dry, rocky planets in our own infant solar system. Thats in addition to the rocky materials that helped create our planet. For G238-44, that means an interesting amalgamation of stuff from a variety of regions and the evidence shows it.

The best fit for our data was a nearly two-to-one mix of Mercury-like material and comet-like material, which is made up of ice and dust, Johnson said. Iron metal and nitrogen ice each suggest wildly different conditions of planetary formation. There is no known solar system object with so much of both.

The death of this sun-like star and its penchant for gobbling up debris has another interesting twist. Billions of years ago, comets and asteroids likely delivered water to our planet, sparking the conditions necessary for life. According to Benjamin Zuckerman, UCLA professor of physics and astronomy, the combo of icy and rocky material detected raining onto G238-44 shows that other planetary systems may have icy reservoirs (like the Kuiper Belt and Oort Cloud). Thats in addition to rocky bodies such as Earth and the asteroids.

Life as we know it requires a rocky planet covered with a variety of volatile elements like carbon, nitrogen, and oxygen, Zuckerman said. The abundances of the elements we see on this white dwarf appear to have come from both a rocky parent body and a volatile-rich parent bodythe first example weve found among studies of hundreds of white dwarfs.

Its intriguing to think that our own Sun could be doing the same thing in a few billion years. Perhaps some future astronomer on a planet a few dozen light-years away will do the same study that Johnson and his team didand spot the remains of Earth in the white dwarf Suns dying glow.

Dead Stars Cannibalism of its Planetary System is the Most Far-Reaching Ever Witnessed

Dead Star Caught Ripping Up Planetary System

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A Dying Star's Last Act was to Destroy all Its Planets - Universe Today

Untangling the evolution of our home galaxy, the Milky Way, is a challenge similar to mapping the human genome, according to the European Space Agency (ESA). ESA's galaxy mapper, Gaia, takes trillions of measurements of 2 billion of the brightest stars in the sky. Here, we look at what it takes to unpick those measurements to reveal the galaxy's secrets.

On June 13, the Gaia Data Processing and Analysis Consortium (DPAC), a collaboration of 450 European astronomers and engineers supporting the galaxy-mapping endeavor, released what DPAC chair Anthony Brown described as "the richest set of astronomical data ever published."

To create the 10-terabyte catalog of compressed data, DPAC computers had to ingest 940 billion observations of 2 billion of the brightest light sources in the sky, Brown, an astronomer at Leiden University in the Netherlands, said at an ESA news conference on June 13.

Related: New trove of Gaia data will uncloak the Milky Way's dark past and future

The data, captured by Gaia between June 2014 and June 2017, contained information about 1.5 billion stars' precise positions and motions in the sky; details about the ages, temperatures and brightness levels of about half a billion of those stars; and detailed chemical compositions of several million of them.

It took five years for the data to pass through the sophisticated computational pipeline of validation, calibration and analysis procedures, which involve six supercomputing centers in six European countries. It would take a thousand years for a single (and rather powerful) personal computer to process the data set, Gonzalo Gracia, DPAC project coordinator for data processing, told Space.com.

As of 2022, the main Gaia database contains 1 petabyte of data, Gracia added, which is equivalent to the data capacity of 200,000 DVDs. To date, the telescope has made over 100 measurements of every single one of the 2 billion light sources it sees.

"Every day, Gaia sends us between 20 and 100 gigabytes of data," Gracia said. "That might not seem like that much if you compare it to the bandwidth you have at home, but we are talking about a satellite that is 1.5 million kilometers [930,000 miles] away from Earth."

From Gaia's vantage point at Lagrange Point 2, a stable point in the sun-Earth system where the gravitational pulls of the two bodies are in balance, the spacecraft observes the cosmos while shielded from the sun's glare.

Three ESA deep-space antennas (one each near Madrid; Malarge, Argentina; and New Norcia, Australia) receive the data collected by the space probe's two telescopes and other instruments. From those ground stations, the measurements travel on conventional internet lines to the European Space Operations Centre in Darmstadt, Germany, for basic checks, before the data are sent to the agency's Science Operations Center in Madrid.

"This is when we do the first round of processing," Gracia said. "We do some initial calibrations and run the data through a piece of software to assess the health of the satellite. This happens in the first hours after the data is received."

Then, things start to get complicated. A data-processing center at CNES, the French space agency, in Toulouse scans the data set for fast-moving objects in the solar system: asteroids and comets that might be on a collision course with Earth.

"They have a pipeline, which detects those objects and checks whether they are already known," Gracia said. "If they are not known, they raise an alarm with the solar system objects community in the world, who can do the follow-up observation and find what the object is about and what is its trajectory."

Gaia is quite efficient in monitoring asteroids and might even be able to see some that are not visible from Earth. The mission's June 13 data release contained information about detailed trajectories of 60,000 solar system space rocks. On top of that, Gaia measured light spectra of these space rocks, revealing their chemical compositions. Previously, astronomers knew detailed chemical compositions of only 4,500 asteroids.

Separately, a team in Cambridge, England, compares new brightness measurements delivered by Gaia with data acquired earlier. Significant changes in brightness levels of stars are always a reason for excitement, as they might indicate supernovas, explosions that occur when massive stars die before collapsing into black holes or neutron stars.

Sometimes, dim distant stars and galaxies can temporarily lighten up through microlensing, an odd phenomenon that happens when an extremely massive object comes between the dim star and the observer, its powerful light-bending gravity acting as a magnifying glass. Gaia, which completes a scan of the entire sky every two months, sees all that.

In the meantime, the rest of the consortium conducts what Gracia calls "cyclic processing": endless rounds of redigesting, validating and analyzing the data to extract the most accurate information that astronomers can use to create precise maps of the Milky Way galaxy and model its life into the past and future. Several thousand servers running tens of thousands of core processors are involved in the operation.

"We have to process the data several times," Gracia said. "We process it, we give it to the scientists for checks, and then we have to tune our calibrations, our algorithms; we have to improve them every time."

The data sets are also dependent on each other. For example, without information about precise positions of the observed objects, the data on brightness changes or movements of asteroids would be worthless.

"We essentially have the information about the amount of photons hitting the Gaia telescopes, and from their position in the window, we derive the positions in the sky," Gracia said. "This is done in Barcelona, where we produce this astrometric information for all the sources in the sky. This is the input for basically all the other processing that we do. It takes a lot of time to do all that and to do it with a sufficient amount of data to ensure that the data is really of the best quality."

This amount of processing is the reason behind the delay between the acquisition of the data and its release. Gaia launched in December 2013, but the astronomical community didn't get their hands on the first batch of data until September 2016. The second data release followed in April 2018. The June 13 data dump was preceded by a partial early release in December 2020. Each new catalog increases the precision of the data as well as the amount of available information about each of the 2 billion light sources the telescope sees. Although the mission is already in its ninth year, there is no stopping for the 450 researchers and engineers at DPAC.

While the world's Milky Way researchers are unpacking the gifts of the June 13 data release, looking for evidence of the galaxy's dynamic life, Gracia and his colleagues are already busy working on the next data dump, which promises, among other things, to unleash Gaia's potential to spot planets around faraway stars. Thousands of new finds are expected to enrich the existing exoplanet catalog as the DPAC researchers train their algorithms to spot the characteristic mild dimming of a star caused by a planet crossing in front of its disk.

"We started processing data for the fourth cycle two years ago and are already planning the fifth cycle," Gracia said. "It's really nonstop."

Follow Tereza Pultarova on Twitter @TerezaPultarova. Follow us on Twitter @Spacedotcom and on Facebook.

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Untangling the Milky Way's evolution through big-data astronomy - Space.com