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Huge Craters On an Asteroid Psyche Could Provide Clues to Early Planets

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Another investigation that forms the structure of massive craters on asteroid 16 Psyche is providing new perspectives on one of the most persistent mysteries of the Solar System, whether the metallic object is the open core of an unsuccessful planet or a complex of debris formed during numerous collisions.

The scientists in the Lunar and Planetary Laboratory of the University of Arizona are the researchers who conducted the study, which was published in JGR Planets, and dedicated to the possibility of unlocking the inner composition of Psyche due to a large impact basin located near the north pole of the asteroid. The results will likely inform the interpretation of the data of the NASA Psyche space probe, which will visit the asteroid in the year 2029.

The largest known metal-rich asteroid is psyche, which is found in the prime asteroid belt separating mars and Jupiter and is one of the heaviest bodies found in the area. Its bizarre structure has been a long-standing puzzle to scientists, and rival theories have proposed that it might be the rocky and metallic inertia of an early planet, or of violent impact that caused the mixing of metals and rock over time.

To experiment with such situations, scientists ran high-speed crashes on a 3-D model of Psyche which was how a crater similar to 30 miles across and three miles deep was formed. The differing impact conditions and internal structures allowed the team to come up with predictions regarding the way various compositions would form the resulting crater and the surrounding debris.

According to the simulations, porosity, which is the empty space in the asteroid, is an important factor that affects the crater formation. This is different to solid planetary bodies, most asteroids are loose or fractured and thus can absorb impact energy in a different manner. Impacts in more porous structures will create deeper and steeper craters and less material ejected on the surface.

Asteroid layered metallic core

There were two main models of the interior of Psyche tested in the study: the asteroid is layered reaching a dense metallic core and thin rocky mantle, and the second one is that the metal and silicate materials are evenly intermingled. Although both scenarios could result in the measured crater sizes, each scenario created a different ejecta pattern and internal compression pattern.

These variations, according to researchers, may turn out to be important suggestions when there would be direct observations. Equipments in the Psyche spacecraft will capture the surface composition of the asteroid, gravity and magnetic field, an assessment of the difference in density that could have occurred due to impact in the past.

Scientists compare the research to the reconstruction of a process that has been abandoned long ago based on its remains. Through surface studies of craters and patterns of debris those studying them hope to be able to determine the internal composition of a body that might be able to tell us about the very earliest phases of planetary formation.

Origin of Psyche

The theory of the origin of Psyche has more far-reaching consequences in the field of planetary science. The discovery of the asteroid as an exposed core would give an opportunity to study processes that formed rocky planets such as Earth processes that are otherwise not reachable since planetary cores are buried deep within thick mantles.

Another theme addressed in the study is the increased importance of advanced simulations in space mission preparation. Predicting tests set in advance before the arrival of the spacecraft, researchers want to speed up the analysis of the information once the real-time stream of information arrives.

Psyche mission, which was initiated by Arizona State University and is supported by NASA Jet Propulsion Laboratory and other organizations belongs to NASA Discovery Program. By the time the spacecraft arrives at its destination towards the end of this decade, scientists are hopeful that it will provide the first close-up view of a metallic world – and possibly end a two hundred plus century long debate.

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New NASA DART mission data reveals asteroids throw ‘cosmic snowballs’ at each other

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Binary asteroid systems are not uncommon in our cosmic neighborhood with about 15 percent of asteroids around the Earth having small moons around them.

A team of astronomers (headed by the University of Maryland) has since found that these binary asteroid systems are much more dynamic than they thought- involving active exchange of rocks and dust in slow, slow-motion collisions that reform them over millions of years.

Upon the analysis of the images captured by the NASA Double Asteroid Redirection Test (DART) spacecraft just before deliberately colliding with the asteroid moon Dimorphos in 2022, the team observed bright, fan-shaped streaks across the surface of the moon, which is the first direct evidence of the material naturally traveling between two asteroids. The implications of the findings given by the researchers in The Planetary Science Journal on March 6, 2026, regarding the information about asteroids that may pose a threat to the earth are far reaching.

Initially, we assumed that it must have been a problem with the camera, then we assumed it must have been a problem with our processing of the images, said the lead author of the paper, Jessica Sunshine, a professor with joint appointments in both the Department of Astronomy and Department of Geological, Environmental, and Planetary Sciences of UMD. However, once we cleared it up we found the marks we were observing were quite regular with respect to low velocity collisions, such as tossing cosmic snowballs. We possessed the first direct evidence of material movement within the recent past in a binary asteroid system.

The results of the team were also the first, visual confirmation of the Yarkovsky-O Keefe Radzievskii Paddak (YORP) effect wherein small asteroids rapidly rotate due to the presence of sunlight, causing material to be thrown off their surfaces to form moons. This was probably true of Didymos and its smaller satellite Dimorphos in the case of Sunshine reported the remnants of the so-called cosmic snowballs which had been deposited on the surface of Dimorphos.

How they found these traces?

They took months of investigative efforts to find these traces. The original images captured by the DART spacecraft could not see the fan-shaped streaks yet, UMD astronomy research scientist Tony Farnham and former postdoctoral researcher Juan Rizos developed more intricate methods to eliminate the boulder shadow and lightning effects in the images and exposed the eye-opening streaks that were left behind by the ‘cosmic snowballs’.

We finally saw these rays wrapping round Dimorphos, something no one has ever seen, you see, Farnham said. At the initial stages, it could not be believed because it was gentle and distinct.

To the researchers, the path of the DART mission provided a peculiar challenge. The space ship flew directly into the target with only slight distinctions in lighting and viewpoint that made it hard to differentiate actual features and any potential lighting possibilities. To demonstrate the authenticity of the streaks the team traced them to the source in one of the areas near the edge of Dimorphos- clearly out of phase with where the sun was overhead. Having done this, the team came to the conclusion that the traces left by the so-called cosmic snowballs were not really a light illusion.

Not fainter as we smoothed out the 3D image of the moon the fan-shaped streaks became more distinct, Farnham said. “It made us sure that we were dealing with a reality.

Earlier researchers noted an indirect evidence of the sunlight causing small asteroids to spin faster triggering the expulsion of material off their surfaces. However, the recently perfected models of the asteroid moon Dimorphos created by the UMD team give the first graphic assurance of the process and the precise sites of the shed material of its original asteroid, Didymos. Additional calculations by UMD alumnus Harrison Agrusa (M.S. ’19, Ph.D. ’22, astronomy) also indicated that the material moved Didymos at 30.7 centimeters per second, which is slower than the typical pace of a human walking.

Fan-shaped marks

“That would be why it had the fan-shaped marks,” Sunshine said. “These slow moving effects would not cause a crater as they would cause a deposit instead of being evenly distributed. And they are focused on the equator as theorized on modeling material ripped off the primary.”

The researchers headed by the former UMD postdoctoral associate Esteban Wright conducted a battery of experiments in their laboratories to test their hypotheses at the UMD Institute of Physical Science and Technology. To replicate boulders on Dimorphos, they tossed marbles into a sand filled with painted gravel. The experiment was recorded with high-speed cameras, and it was found that boulders filtered some material and allowed other particles to stream in-between the boulders- forming ray-like patterns similar to those found on Dimorphos.

The results were verified in computer simulations of effects of loose clumps of dust done at Lawrence Livermore National Laboratory. The shape of the fan-shaped rays on the surface of the asteroid was naturally formed by boulders that formed the cosmic snowballs on the surface of the asteroid whether the impactor was a compact rock such as the marble or a loose clump of material.

These marks could be seen on Dimorphos in that film taken by the DART spacecraft immediately before the large collision, evidence that there was an exchange of material between it and Didymos, said Sunshine. The fan line deposit must stretch up to the side of the moon that we did not strike and there is a chance that it was not smashed in by the blow.

These features could be found to be still present on Didymos as the Hera mission of the European Space Agency will possibly arrive in December 2026 and see them. Sunshine and her colleagues give an estimate as to how Hera will also witness new ray patterns formed when boulders are struck by the DART spacecraft, knocking them loose, which gives them a different perspective of the asteroids that have the potential to threaten the earth.

According to Sunshine, these new findings which arise out of this research play a critical part in our knowledge about the near-Earth asteroids and their evolutionary patterns. It has been discovered that they are much more dynamic than we thought before and this will assist us in streamlining our models and our planetary defense efforts.

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Mars lander records sound of meteoroids hitting Red Planet (Listen Now)

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The Mars lander’s seismometer has picked up vibrations from four separate impacts in the past two years, which is the first of its kind to have recorded seismic and acoustic waves from an impact on the Red Planet.

NASA’s InSight lander has detected seismic waves from four space rocks that crashed on Mars in 2020 and 2021, detected by the spacecraft’s seismometer since its landing in 2018.

A new paper published Monday in Nature Geoscience details the impacts, which ranged between 53 and 180 miles (85 and 290 kilometers) from InSight’s location, a region of Mars called Elysium Planitia.

The first of the four confirmed meteoroids – the term used for space rocks before they hit the ground – made the most dramatic entrance: It entered Mars’ atmosphere on Sept. 5, 2021, exploding into at least three shards that each left a crater behind.

Credit: NASA/JPL-Caltech

Then, NASA’s Mars Reconnaissance Orbiter flew over the estimated impact site and confirmed the  location using its black-and-white Context Camera to find three darkened spots on the surface. After locating these spots, the orbiter used the High-Resolution Imaging Science Experiment camera, or HiRISE, to get a color close-up of the craters.

“After three years of InSight waiting to detect an impact, those craters looked beautiful,” said Ingrid Daubar of Brown University, a co-author of the paper and a specialist in Mars impacts. Finally, scientists confirmed three other impacts had occurred on May 27, 2020; Feb. 18, 2021; and Aug. 31, 2021.

Researchers have puzzled over why they haven’t detected more meteoroid impacts on Mars. The Red Planet is next to the solar system’s main asteroid belt, which provides an ample supply of space rocks to scar the planet’s surface. Because Mars’ atmosphere is just 1% as thick as Earth’s, more meteoroids pass through it without disintegrating.

InSight’s seismometer has also detected over 1,300 marsquakes. Provided by France’s space agency, the Centre National d’Études Spatiales, the instrument is so sensitive that it can detect seismic waves from thousands of miles away. But the Sept. 5, 2021, event marks the first time an impact was confirmed as the cause of such waves.

InSight’s team suspects that other impacts may have been obscured by noise from wind or by seasonal changes in the atmosphere. But now that the distinctive seismic signature of an impact on Mars has been discovered, scientists expect to find more hiding within InSight’s nearly four years of data.

Listen to a Meteoroid Hitting the Red Planet

The sound of a meteoroid striking Mars – created from data recorded by NASA’s InSight lander – is like a “bloop” due to a peculiar atmospheric effect. In this audio clip, the sound can be heard three times: when the meteoroid enters the Martian atmosphere, explodes into pieces, and impacts the surface.

The four meteoroid impacts confirmed so far produced small quakes with a magnitude of no more than 2.0. Those smaller quakes provide scientists with only a glimpse into the Martian crust, while seismic signals from larger quakes, like the magnitude 5 event that occurred in May 2022, can also reveal details about the planet’s mantle and core.

But the impacts will be critical to refining Mars’ timeline. “Impacts are the clocks of the solar system,” said the paper’s lead author, Raphael Garcia of Institut Supérieur de l’Aéronautique et de l’Espace in Toulouse, France. “We need to know the impact rate today to estimate the age of different surfaces.”

Scientists can approximate the age of a planet’s surface by counting its impact craters: The more they see, the older the surface. By calibrating their statistical models based on how often they see impacts occurring now, scientists can then estimate how many more impacts happened earlier in the solar system’s history.

InSight’s data, in combination with orbital images, can be used to rebuild a meteoroid’s trajectory and the size of its shock wave. Every meteoroid creates a shock wave as it hits the atmosphere and an explosion as it hits the ground. These events send sound waves through the atmosphere. The bigger the explosion, the more this sound wave tilts the ground when it reaches InSight. The lander’s seismometer is sensitive enough to measure how much the ground tilts from such an event and in what direction.

“We’re learning more about the impact process itself,” Garcia said. “We can match different sizes of craters to specific seismic and acoustic waves now.”

The lander still has time to study Mars. Dust buildup on the lander’s solar panels is reducing its power and will eventually lead to the spacecraft shutting down. Predicting precisely when is difficult, but based on the latest power readings, engineers now believe the lander could shut down between October of this year and January 2023.