Rare and highly sought after, these celestial pebbles are a source of great joy to scientists and private collectors alike. If they are sufficiently massive, these rocks pass through the atmosphere leaving a fiery trail, landing on the surface in the form of meteorites. Impacts and collisionsīillions of years ago, when Mars and Earth were formed from the cloud of dust and gas that surrounded the young Sun, their surfaces were continually bombarded by showers of asteroids and comets that left spectacular scars in the form of craters.įortunately, the skies today have become much calmer, but occasionally in its voyage around the Sun the Earth encounters rocky fragments wandering aimlessly through interplanetary space. Should it prove to be the case, a celestial phenomenon will nonetheless be used to advantage to probe the interior of Mars: asteroid impacts. This plausible situation has been taken into account by the scientists involved in the InSight mission. ![]() The Red Planet may actually be geologically dead, a still and frozen rocky globe circling the Sun. However, it is entirely possible that Mars has stopped trembling for good, having exhausted all its internal heat. To probe the depths of Mars and determine its internal structure, the InSight mission relies first and foremost on the planet’s seismic life.Īlthough seismologists expect a level of seismic activity much lower than that on Earth, they nonetheless hope to see a few quakes during the mission and take advantage of the seismic waves generated by the tremors to pierce the mysteries of Mars’ planetary interior. Known as the Terra Cimmeria-Sirenum province, it is "a relic of the early crustal processes on Mars, and thus, a region of high interest for future missions," the study said.īouley pointed to a "bias" in the currently planned missions to Mars in favor of searching for signs of water and life.īut to understand how planets first formed would answer some fundamental questions, Lagain said, including "how Earth became such an exceptional planet in the Universe.A natural source of seismic waves, meteorite impacts will be a valuable ally for InSightĪ recent impact on the surface of Mars (© NASA/JPL/University of Arizona). "The region where Karratha was found is the most magnetized on Mars," Lagain said. The region in Mars' southern hemisphere is rich in the elements potassium and thorium, just like Black Beauty.Īnother factor was that Black Beauty is the only Martian meteorite that is highly magnetized. Then a few million years ago, another asteroid hit not far away, creating the 10-kilometer Karratha crater and shooting the Black Beauty towards Earth. They found that Black Beauty was dug up from its first home by an asteroid that struck around 1.5 billion years ago, forming the 40-kilometer Khujirt crater. That narrowed it down to 19 craters, allowing the researchers to rule out the remaining suspects. The team then created an algorithm and used a supercomputer to trawl through images of 90 million craters taken by a NASA satellite. ![]() "So, we were looking for a crater that was very young and large," Lagain said.Īnother clue was that its composition showed it had suddenly heated up around 1.5 million years ago –- likely by the impact of a second asteroid. The problem? The pockmarked surface of Mars has around 80,000 craters at least that big.īut the researchers had a clue: by measuring Black Beauty's exposure to cosmic rays, they knew it was dislodged from its first home around 5 million years ago. Such a crater would have to be massive – at least 3 kilometers in diameter. ![]() The impact "had enough force to eject the rocks at very high speed – more than 5 kilometers (3 miles) a second – to escape the Martian gravity," Curtin's Anthony Lagain, the lead author of the study in Nature Communications, told AFP. They knew that it was likely an asteroid hitting the red planet that sent Black Beauty shooting up into space.
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