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By NASA
Illustration of the main asteroid belt, orbiting the Sun between Mars and JupiterNASA NASA’s powerful James Webb Space Telescope includes asteroids on its list of objects studied and secrets revealed.
A team led by researchers at the Massachusetts Institute of Technology (MIT) in Cambridge repurposed Webb’s observations of a distant star to reveal a population of small asteroids — smaller than astronomers had ever detected orbiting the Sun in the main asteroid belt between Mars and Jupiter.
The 138 new asteroids range from the size of a bus to the size of a stadium — a size range in the main belt that has not been observable with ground-based telescopes. Knowing how many main belt asteroids are in different size ranges can tell us something about how asteroids have been changed over time by collisions. That process is related to how some of them have escaped the main belt over the solar system’s history, and even how meteorites end up on Earth.
“We now understand more about how small objects in the asteroid belt are formed and how many there could be,” said Tom Greene, an astrophysicist at NASA’s Ames Research Center in California’s Silicon Valley and co-author on the paper presenting the results. “Asteroids this size likely formed from collisions between larger ones in the main belt and are likely to drift towards the vicinity of Earth and the Sun.”
Insights from this research could inform the work of the Asteroid Threat Assessment Project at Ames. ATAP works across disciplines to support NASA’s Planetary Defense Coordination Office by studying what would happen in the case of an Earth impact and modeling the associated risks.
“It’s exciting that Webb’s capabilities can be used to glean insights into asteroids,” said Jessie Dotson, an astrophysicist at Ames and member of ATAP. “Understanding the sizes, numbers, and evolutionary history of smaller main belt asteroids provides important background about the near-Earth asteroids we study for planetary defense.”
Illustration of the James Webb Space TelescopeNASA The team that made the asteroid detections, led by research scientist Artem Burdanov and professor of planetary science Julien de Wit, both of MIT, developed a method to analyze existing Webb images for the presence of asteroids that may have been inadvertently “caught on film” as they passed in front of the telescope. Using the new image processing technique, they studied more than 10,000 images of the star TRAPPIST-1, originally taken to search for atmospheres around planets orbiting the star, in the search for life beyond Earth.
Asteroids shine more brightly in infrared light, the wavelength Webb is tuned to detect, than in visible light, helping reveal the population of main belt asteroids that had gone unnoticed until now. NASA will also take advantage of that infrared glow with an upcoming mission, the Near-Earth Object (NEO) Surveyor. NEO Surveyor is the first space telescope specifically designed to hunt for near-Earth asteroids and comets that may be potential hazards to Earth.
The paper presenting this research, “Detections of decameter main-belt asteroids with JWST,” was published Dec. 9 in Nature.
The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
For news media:
Members of the news media interested in covering this topic should reach out to the NASA Ames newsroom.
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By NASA
Artist’s concept depicts new research that has expanded our understanding of exoplanet WASP-69 b’s “tail.” NASA/JPL-Caltech/R. Hurt (IPAC) The Planet
WASP-69 b
The Discovery
The exoplanet WASP-69 b has a “tail,” leaving a trail of gas in its wake.
Key Takeaway
WASP-69 b is slowly losing its atmosphere as light hydrogen and helium particles in the planet’s outer atmosphere escape the planet over time. But those gas particles don’t escape evenly around the planet, instead they are swept into a tail of gas by the stellar wind coming from the planet’s star.
Details
Hot Jupiters like WASP-69 b are super-hot gas giants orbiting their host stars closely. When radiation coming from a star heats up a planet’s outer atmosphere, the planet can experience photoevaporation, a process in which lightweight gases like hydrogen and helium are heated by this radiation and launched outward into space. Essentially, WASP-69 b’s star strips gas from the planet’s outer atmosphere over time.
What’s more, something called the stellar wind can shape this escaping gas into an exoplanetary tail.
The stellar wind is a continuous stream of charged particles that flow outwards into space from a star’s outer atmosphere, or corona. On Earth, the Sun’s stellar wind interacts with our planet’s magnetic field which can create beautiful auroras like the Northern Lights.
On WASP-69 b, the stellar wind coming from its host star actually shapes the gas escaping from the planet’s outer atmosphere. So, instead of gas just escaping evenly around the planet, “strong stellar winds can sculpt that outflow in tails that trail behind the planet,” said lead author Dakotah Tyler, an astrophysicist at the University of California, Los Angeles, likening this gaseous tail to a comet’s tail.
Because this tail is created by the stellar wind, however, that means it’s subject to change.
“If the stellar wind were to taper down, then you could imagine that the planet is still losing some of its atmosphere, but it just isn’t getting shaped into the tail,” Tyler said, adding that, without the stellar wind, that gas escaping on all sides of the planet would be spherical and symmetrical. “But if you crank up the stellar wind, that atmosphere then gets sculpted into a tail.”
Tyler likened the process to a windsock blowing in the breeze, with the sock forming a more structured shape when the wind picks up and it fills with air.
The tail that Tyler and his research team observed on WASP-69 b extended more than 7.5 times the radius of the planet, or over 350,000 miles. But it’s possible that the tail is even longer. The team had to end observations with the telescope before the tail’s signal disappeared, so this measurement is a lower limit on the tail’s true length at the time.
However, keep in mind that because the tail is influenced by the stellar wind, changes in the stellar wind could change the tail’s size and shape over time. Additionally changes in the stellar wind influence the tail’s size and shape, but since the tail is visible when illuminated by starlight, changes in stellar activity can also affect tail observations.
Exoplanet tails are still a bit mysterious, especially because they are subject to change. The study of exoplanet tails could help scientists to better understand how these tails form as well as the ever-changing relationship between the stellar and planetary atmospheres. Additionally, because these exoplanetary tails are shaped by stellar activity, they could serve as indicators of stellar behavior over time. This could be helpful for scientists as they seek to learn more about the stellar winds of stars other than the star we know the most about, our very own Sun.
Fun Facts
WASP-69 b is losing a lot of gas — about 200,000 tons per second. But it’s losing this gaseous atmosphere very slowly — so slowly in fact that there is no danger of the planet being totally stripped or disappearing. In general, every billion years, the planet is losing an amount of material that equals the mass of planet Earth.
The solar system that WASP-69 b inhabits is about 7 billion years old, so even though the rate of atmosphere loss will vary over time, you might estimate that this planet has lost the equivalent of seven Earths (in mass) of gas over that period.
The Discoverers
A team of scientists led by Dakotah Tyler of the University of California, Los Angeles published a paper in January, 2024 on their discovery, “WASP-69b’s Escaping Envelope Is Confined to a Tail Extending at Least 7 Rp,” in the journal, “The Astrophysical Journal.” The observations described in this paper were made by Keck/NIRSPEC (NIRSPEC is a spectrograph designed for Keck II).
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By European Space Agency
Video: 00:00:23 From 7 until 13 October 2024, ESA/NASA’s SOHO spacecraft recorded Comet C/2023 A3 (Tsuchinshan–ATLAS), the second brightest comet it has ever seen. Meanwhile, large amounts of material were being spewed out by the Sun (covered in the centre), and planet Mercury is visible to the left.
The comet’s nucleus is clearly visible, surrounded by a dusty coma and trailing an impressively long tail. SOHO sees the large dust tail edge-on, curving in on itself as it is pushed outward by solar wind.
At the end of the video you can also see a rare phenomenon known as an ‘anti-tail’: a long, thin line that points towards the Sun. This tail is an optical illusion coming from SOHO getting an edge-on view of the larger cometary dust particles that accumulate in the comet’s orbital plane.
Comet C/2023 A3 was seen for the first time early last year. It most likely came from the distant Oort cloud, and the last time this comet flew through the inner Solar System (if ever) was at least 80 000 years ago.
The comet reached an estimated peak brightness just beyond –4 magnitude. (The more negative the visual magnitude value, the brighter the object.) Of the more than 5000 comets SOHO has seen flying past the Sun, only Comet C/2006 P1 (McNaught) was brighter, with a visual magnitude of –5.5.
SOHO’s location between the Sun and Earth gave it a front-row seat, but the same comet has been visible from Earth every evening since 12 October 2024. Throughout October, as the comet moves farther away from the Sun, it will gradually grow fainter and rise higher up in the western sky.
The week that SOHO watched Comet Tsuchinshan–ATLAS was also a wild one in terms of space weather. The Sun unleashed no less than 4 X-class flares (the highest intensity type of flare), 28 medium-intensity M-class flares, and 31 coronal mass ejections – the latter being visible as white clouds of material in the video. All this activity led to two geomagnetic storms on Earth, resulting in beautiful auroras lighting up the night sky.
SOHO, short for Solar and Heliospheric Observatory, is a joint ESA-NASA mission to study the Sun. For almost 29 years now, it has been watching the Sun itself as well as the much fainter light coming from the Sun’s outer atmosphere, called the solar corona. The data shown in this video were taken by the LASCO C3 coronagraph instrument.
Special thanks to Simeon Schmauß, who processed the raw data to create this impressive video. For comparison, here is a video of the comet with more standard data processing – the comet is so bright that it partially saturated SOHO’s sensor.
What types of comets are there?
How are comets named?
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By NASA
2 min read
ESA/NASA’s SOHO Spies Bright Comet Making Debut in Evening Sky
The tail of comet C/2023 A3 Tsuchinshan-ATLAS spanned the view of the Solar and Heliospheric Observatory (SOHO) on Oct. 10, 2024. ESA/NASA The ESA (European Space Agency) and NASA Solar and Heliospheric Observatory (SOHO) has captured images of the second-brightest comet to ever pass through its field of view during the spacecraft’s nearly 29-year career.
The bright comet is C/2023 A3 Tsuchinshan-ATLAS, which has been garnering a lot of attention from skywatchers recently, displaying a long, dusty tail in pre-dawn skies throughout late September and early October. (Comet McNaught, viewed in 2007, holds the record as the brightest comet SOHO has seen.)
Between Oct. 7 and 11, the comet blazed through the view of SOHO’s LASCO (Large Angle and Spectrometric Coronagraph Experiment) instrument, which uses a disk to block out the bright light of the Sun so it’s easier to see details and objects near the Sun. This image, taken by SOHO on Oct. 10, 2024, shows the comet and its bright tail streaming from the upper left to the right. Mercury appears as a bright dot on the left.
After crossing through SOHO’s field of view, the comet will begin putting on an evening show for skywatchers around the world just after sunset starting Saturday, Oct. 12. Each day throughout October, the comet will gradually rise higher and higher in the western sky as it moves farther away from the Sun. But as it does, it will become fainter and fainter. Eagle-eyed skywatchers may be able to spot it with the naked eye for a few days, but after that, observers will likely need binoculars or a telescope to see it as it grows fainter.
Even if you are unable to spot this comet yourself, you can help SOHO search for others. Scientists and members of the general public have discovered more than 5,000 comets in SOHO imagery, and you can help find even more by visiting the Sungrazer Project.
By Vanessa Thomas
NASA’s Goddard Space Flight Center, Greenbelt, Md.
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Last Updated Oct 11, 2024 Related Terms
Comets Goddard Space Flight Center Heliophysics Heliophysics Division Skywatching SOHO (Solar and Heliospheric Observatory) The Sun The Sun & Solar Physics Explore More
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By USH
Where do asteroids get all those craters? Countless small circular craters, plus almost always a few that look like massive killers. Even more confusing is that these craters are at a perfect 90º angle, as if an electric arc had run across the surface.
According to ThunderboltsProject, the Electric Universe (EU) model, the scars observed on asteroids are caused by electric arcs which cut surface depressions, scoop out material, accelerate it into space, then leave behind clean-cut geological relief.
This theory is supported by Electric Discharge Machining (EDM), a process we use every day to shape materials with electric arcs, producing similar clean-cut effects.
This brings us to the following hypothesis: Could it be that, instead of craters on asteroids being formed solely by natural space phenomena, that all these craters at a perfect 90º angle with clean-cut geological relief are the result of asteroid mining originated by alien races who use advanced electric arc/laser technology by extracting raw minerals they urgently need for use on their planet or for in-space manufacturing?
Asteroids vary greatly in composition, ranging from those rich in volatile substances to those composed of metals like gold, silver, platinum, cobalt, and palladium, alongside more common elements such as iron and nickel. This makes them potential treasure troves of valuable resources.
For us as Earthlings, asteroid mining is a technology in its earliest stages and requires significant advances in robotic technology before asteroid mining becomes a reality, however, if more advanced civilizations exist elsewhere in the universe, it's quite plausible that some of them have already turned to asteroid mining long ago.
Could their efforts be leaving behind the very craters on asteroids we observe today?
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