6 min read<\/p>\n
Preparations for Next Moonwalk Simulations Underway (and Underwater)<\/h1>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n![\"Artist's](\"https:\/\/www.nasa.gov\/wp-content\/uploads\/2025\/08\/1-pia26635-illustration-giant-asteroid-impacting-ancient-mars.jpg?w=2048\")
<\/a><\/figure>\nScientists believe giant impacts \u2014 like the one depicted in this artist\u2019s concept \u2014 occurred on Mars 4.5 billion years ago, injecting debris from the impact deep into the planet\u2019s mantle. NASA\u2019s InSight lander detected this debris before the mission\u2019s end in 2022.<\/div>\nNASA\/JPL-Caltech<\/div>\n<\/figcaption><\/div>\n<\/div>\n<\/div>\nRocky material that impacted Mars lies scattered in giant lumps throughout the planet\u2019s mantle, offering clues about Mars\u2019 interior and its ancient past.<\/em><\/p>\nWhat appear to be fragments from the aftermath of massive impacts on Mars that occurred 4.5 billion years ago have been detected deep below the planet\u2019s surface. The discovery was made thanks to NASA\u2019s now-retired InSight lander, which recorded the findings before the mission\u2019s end in 2022. The ancient impacts released enough energy to melt continent-size swaths of the early crust and mantle into vast magma oceans, simultaneously injecting the impactor fragments and Martian debris deep into the planet\u2019s interior.<\/p>\n
There\u2019s no way to tell exactly what struck Mars: The early solar system was filled with a range of different rocky objects that could have done so, including some so large they were effectively protoplanets. The remains of these impacts still exist in the form of lumps that are as large as 2.5 miles (4 kilometers) across and scattered throughout the Martian mantle. They offer a record preserved only on worlds like Mars, whose lack of tectonic plates has kept its interior from being churned up the way Earth\u2019s is through a process known as convection.<\/p>\n
\n\n\n![\"A](\"https:\/\/www.nasa.gov\/wp-content\/uploads\/2025\/08\/e1-pia26636-illustration-cutaway-showing-asteroid-debris-in-mars-mantle.jpg?w=2048\")
<\/a><\/figure>\nA cutaway view of Mars in this artist\u2019s concept (not to scale) reveals debris from ancient impacts scattered through the planet\u2019s mantle. On the surface at left, a meteoroid impact sends seismic signals through the interior; at right is NASA\u2019s InSight lander.<\/div>\nNASA\/JPL-Caltech<\/div>\n<\/figcaption><\/div>\n<\/div>\n<\/div>\nThe finding was reported Thursday, Aug. 28, in a study <\/a>published by the journal Science.<\/p>\n\u201cWe\u2019ve never seen the inside of a planet in such fine detail and clarity before,\u201d said the paper\u2019s lead author, Constantinos Charalambous of Imperial College London. \u201cWhat we\u2019re seeing is a mantle studded with ancient fragments. Their survival to this day tells us Mars\u2019 mantle has evolved sluggishly over billions of years. On Earth, features like these may well have been largely erased.\u201d<\/p>\n
InSight<\/a>, which was managed by NASA\u2019s Jet Propulsion Laboratory in Southern California, placed the first seismometer<\/a> on Mars\u2019 surface in 2018. The extremely sensitive instrument recorded 1,319 marsquakes before the lander\u2019s end of mission in 2022<\/a>.<\/p>\n\n\n\n![\"A](\"https:\/\/www.nasa.gov\/wp-content\/uploads\/2022\/05\/1-pia23203-insight_selfie_already_in_pj.png?w=1051\")
<\/a><\/figure>\nNASA\u2019s InSight took this selfie in 2019 using a camera on its robotic arm. The lander also used its arm to deploy the mission\u2019s seismometer, whose data was used in a 2025 study showing impacts left chunks of debris deep in the planet\u2019s interior.<\/div>\nNASA\/JPL-Caltech<\/div>\n<\/figcaption><\/div>\n<\/div>\n<\/div>\nQuakes produce seismic waves that change as they pass through different kinds of material, providing scientists a way to study the interior of a planetary body<\/a>. To date, the InSight team has measured the size, depth, and composition of Mars\u2019 crust, mantle, and core<\/a>. This latest discovery regarding the mantle\u2019s composition suggests how much is still waiting to be discovered within InSight\u2019s data.<\/p>\n\u201cWe knew Mars was a time capsule bearing records of its early formation, but we didn\u2019t anticipate just how clearly we\u2019d be able to see with InSight,\u201d said Tom Pike of Imperial College London, coauthor of the paper.<\/p>\n
Quake hunting<\/strong><\/h3>\nMars lacks the tectonic plates that produce the temblors many people in seismically active areas are familiar with. But there are two other types of quakes on Earth that also occur on Mars: those caused by rocks cracking under heat and pressure, and those caused by meteoroid impacts.<\/p>\n
Of the two types, meteoroid impacts on Mars produce high-frequency seismic waves that travel from the crust deep into the planet\u2019s mantle, according to a paper<\/a> published earlier this year in Geophysical Research Letters. Located beneath the planet\u2019s crust, the Martian mantle can be as much as 960 miles (1,550 kilometers) thick and is made of solid rock that can reach temperatures as high as 2,732 degrees Fahrenheit (1,500 degrees Celsius).<\/p>\nScrambled signals<\/strong><\/h3>\nThe new Science paper identifies eight marsquakes whose seismic waves contained strong, high-frequency energy that reached deep into the mantle, where their seismic waves were distinctly altered.<\/p>\n
\u201cWhen we first saw this in our quake data, we thought the slowdowns were happening in the Martian crust,\u201d Pike said. \u201cBut then we noticed that the farther seismic waves travel through the mantle, the more these high-frequency signals were being delayed.\u201d<\/p>\n
Using planetwide computer simulations, the team saw that the slowing down and scrambling happened only when the signals passed through small, localized regions within the mantle. They also determined that these regions appear to be lumps of material with a different composition than the surrounding mantle.<\/p>\n
With one riddle solved, the team focused on another: how those lumps got there.<\/p>\n
Turning back the clock, they concluded that the lumps likely arrived as giant asteroids or other rocky material that struck Mars during the early solar system, generating those oceans of magma as they drove deep into the mantle, bringing with them fragments of crust and mantle.<\/p>\n
Charalambous likens the pattern to shattered glass \u2014 a few large shards with many smaller fragments. The pattern is consistent with a large release of energy that scattered many fragments of material throughout the mantle. It also fits well with current thinking that in the early solar system, asteroids and other planetary bodies regularly bombarded the young planets.<\/p>\n
On Earth, the crust and uppermost mantle is continuously recycled by plate tectonics pushing a plate\u2019s edge into the hot interior, where, through convection, hotter, less-dense material rises and cooler, denser material sinks. Mars, by contrast, lacks tectonic plates, and its interior circulates far more sluggishly. The fact that such fine structures are still visible today, Charalambous said, \u201ctells us Mars hasn\u2019t undergone the vigorous churning that would have smoothed out these lumps.\u201d<\/p>\n
And in that way, Mars could point to what may be lurking beneath the surface of other rocky planets that lack plate tectonics, including Venus and Mercury.<\/p>\n
More about InSight<\/strong><\/h3>\nJPL managed InSight for NASA\u2019s Science Mission Directorate. InSight was part of NASA\u2019s Discovery Program, managed by the agency\u2019s Marshall Space Flight Center in Huntsville, Alabama. Lockheed Martin Space in Denver built the InSight spacecraft, including its cruise stage and lander, and supported spacecraft operations for the mission.<\/p>\n
A number of European partners, including France\u2019s Centre National d\u2019\u00c9tudes Spatiales (CNES) and the German Aerospace Center (DLR), supported the InSight mission. CNES provided the Seismic Experiment for Interior Structure (SEIS<\/a>) instrument to NASA, with the principal investigator at IPGP (Institut de Physique du Globe de Paris). Significant contributions for SEIS came from IPGP; the Max Planck Institute for Solar System Research (MPS) in Germany; the Swiss Federal Institute of Technology (ETH Zurich) in Switzerland; Imperial College London and Oxford University in the United Kingdom; and JPL. DLR provided the Heat Flow and Physical Properties Package (HP3<\/sup><\/a>) instrument, with significant contributions from the Space Research Center (CBK) of the Polish Academy of Sciences and Astronika in Poland. Spain\u2019s Centro de Astrobiolog\u00eda (CAB) supplied the temperature and wind sensors.<\/p>\nNews Media Contacts<\/strong><\/h3>\nAndrew Good
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-2433
andrew.c.good@jpl.nasa.gov<\/a><\/p>\nKaren Fox \/ Molly Wasser
NASA Headquarters, Washington
202-358-1600
karen.c.fox@nasa.gov<\/a> \/ molly.l.wasser@nasa.gov<\/a><\/p>\n2025-110<\/p>\n
\n\n\n\n\n\nShare<\/h2>\n<\/p><\/div>\n\n
![\"Artist's](\"https:\/\/www.nasa.gov\/wp-content\/uploads\/2025\/08\/1-pia26635-illustration-giant-asteroid-impacting-ancient-mars.jpg\")
<\/a><\/figure>Rocky material that impacted Mars lies scattered in giant lumps throughout the planet\u2019s mantle, offering clues about Mars\u2019 interior and its ancient past.<\/em><\/p>\n What appear to be fragments from the aftermath of massive impacts on Mars that occurred 4.5 billion years ago have been detected deep below the planet\u2019s surface. The discovery was made thanks to NASA\u2019s now-retired InSight lander, which recorded the findings before the mission\u2019s end in 2022. The ancient impacts released enough energy to melt continent-size swaths of the early crust and mantle into vast magma oceans, simultaneously injecting the impactor fragments and Martian debris deep into the planet\u2019s interior.<\/p>\n There\u2019s no way to tell exactly what struck Mars: The early solar system was filled with a range of different rocky objects that could have done so, including some so large they were effectively protoplanets. The remains of these impacts still exist in the form of lumps that are as large as 2.5 miles (4 kilometers) across and scattered throughout the Martian mantle. They offer a record preserved only on worlds like Mars, whose lack of tectonic plates has kept its interior from being churned up the way Earth\u2019s is through a process known as convection.<\/p>\n The finding was reported Thursday, Aug. 28, in a study <\/a>published by the journal Science.<\/p>\n \u201cWe\u2019ve never seen the inside of a planet in such fine detail and clarity before,\u201d said the paper\u2019s lead author, Constantinos Charalambous of Imperial College London. \u201cWhat we\u2019re seeing is a mantle studded with ancient fragments. Their survival to this day tells us Mars\u2019 mantle has evolved sluggishly over billions of years. On Earth, features like these may well have been largely erased.\u201d<\/p>\n InSight<\/a>, which was managed by NASA\u2019s Jet Propulsion Laboratory in Southern California, placed the first seismometer<\/a> on Mars\u2019 surface in 2018. The extremely sensitive instrument recorded 1,319 marsquakes before the lander\u2019s end of mission in 2022<\/a>.<\/p>\n Quakes produce seismic waves that change as they pass through different kinds of material, providing scientists a way to study the interior of a planetary body<\/a>. To date, the InSight team has measured the size, depth, and composition of Mars\u2019 crust, mantle, and core<\/a>. This latest discovery regarding the mantle\u2019s composition suggests how much is still waiting to be discovered within InSight\u2019s data.<\/p>\n \u201cWe knew Mars was a time capsule bearing records of its early formation, but we didn\u2019t anticipate just how clearly we\u2019d be able to see with InSight,\u201d said Tom Pike of Imperial College London, coauthor of the paper.<\/p>\n Mars lacks the tectonic plates that produce the temblors many people in seismically active areas are familiar with. But there are two other types of quakes on Earth that also occur on Mars: those caused by rocks cracking under heat and pressure, and those caused by meteoroid impacts.<\/p>\n Of the two types, meteoroid impacts on Mars produce high-frequency seismic waves that travel from the crust deep into the planet\u2019s mantle, according to a paper<\/a> published earlier this year in Geophysical Research Letters. Located beneath the planet\u2019s crust, the Martian mantle can be as much as 960 miles (1,550 kilometers) thick and is made of solid rock that can reach temperatures as high as 2,732 degrees Fahrenheit (1,500 degrees Celsius).<\/p>\n The new Science paper identifies eight marsquakes whose seismic waves contained strong, high-frequency energy that reached deep into the mantle, where their seismic waves were distinctly altered.<\/p>\n \u201cWhen we first saw this in our quake data, we thought the slowdowns were happening in the Martian crust,\u201d Pike said. \u201cBut then we noticed that the farther seismic waves travel through the mantle, the more these high-frequency signals were being delayed.\u201d<\/p>\n Using planetwide computer simulations, the team saw that the slowing down and scrambling happened only when the signals passed through small, localized regions within the mantle. They also determined that these regions appear to be lumps of material with a different composition than the surrounding mantle.<\/p>\n With one riddle solved, the team focused on another: how those lumps got there.<\/p>\n Turning back the clock, they concluded that the lumps likely arrived as giant asteroids or other rocky material that struck Mars during the early solar system, generating those oceans of magma as they drove deep into the mantle, bringing with them fragments of crust and mantle.<\/p>\n Charalambous likens the pattern to shattered glass \u2014 a few large shards with many smaller fragments. The pattern is consistent with a large release of energy that scattered many fragments of material throughout the mantle. It also fits well with current thinking that in the early solar system, asteroids and other planetary bodies regularly bombarded the young planets.<\/p>\n On Earth, the crust and uppermost mantle is continuously recycled by plate tectonics pushing a plate\u2019s edge into the hot interior, where, through convection, hotter, less-dense material rises and cooler, denser material sinks. Mars, by contrast, lacks tectonic plates, and its interior circulates far more sluggishly. The fact that such fine structures are still visible today, Charalambous said, \u201ctells us Mars hasn\u2019t undergone the vigorous churning that would have smoothed out these lumps.\u201d<\/p>\n And in that way, Mars could point to what may be lurking beneath the surface of other rocky planets that lack plate tectonics, including Venus and Mercury.<\/p>\n JPL managed InSight for NASA\u2019s Science Mission Directorate. InSight was part of NASA\u2019s Discovery Program, managed by the agency\u2019s Marshall Space Flight Center in Huntsville, Alabama. Lockheed Martin Space in Denver built the InSight spacecraft, including its cruise stage and lander, and supported spacecraft operations for the mission.<\/p>\n A number of European partners, including France\u2019s Centre National d\u2019\u00c9tudes Spatiales (CNES) and the German Aerospace Center (DLR), supported the InSight mission. CNES provided the Seismic Experiment for Interior Structure (SEIS<\/a>) instrument to NASA, with the principal investigator at IPGP (Institut de Physique du Globe de Paris). Significant contributions for SEIS came from IPGP; the Max Planck Institute for Solar System Research (MPS) in Germany; the Swiss Federal Institute of Technology (ETH Zurich) in Switzerland; Imperial College London and Oxford University in the United Kingdom; and JPL. DLR provided the Heat Flow and Physical Properties Package (HP3<\/sup><\/a>) instrument, with significant contributions from the Space Research Center (CBK) of the Polish Academy of Sciences and Astronika in Poland. Spain\u2019s Centro de Astrobiolog\u00eda (CAB) supplied the temperature and wind sensors.<\/p>\n Andrew Good Karen Fox \/ Molly Wasser 2025-110<\/p>\n<\/a><\/figure><\/a><\/figure>Quake hunting<\/strong><\/h3>\n
Scrambled signals<\/strong><\/h3>\n
More about InSight<\/strong><\/h3>\n
News Media Contacts<\/strong><\/h3>\n
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-2433
andrew.c.good@jpl.nasa.gov<\/a><\/p>\n
NASA Headquarters, Washington
202-358-1600
karen.c.fox@nasa.gov<\/a> \/ molly.l.wasser@nasa.gov<\/a><\/p>\nShare<\/h2>\n<\/p><\/div>\n