NASA Mission Accidentally Sends Space Rocks Hurtling Towards Mars

NASA Mission Accidentally Sends Space Rocks Hurtling Towards Mars

Well, now we’ve torn it.

A mission to divert the course of an asteroid in September 2022 may have been a wild success, but it hasn’t been without collateral damage.

A new analysis of the debris ejected from the asteroid Dimorphos when NASA slammed the DART spacecraft into it has revealed that some of the rocks could be on a collision course with Mars.

That doesn’t seem like a big deal at the moment, because there’s no one on Mars to worry about… but by the time the rocks are due to intersect with Mars’s orbit, there very well might be, if crewed missions go according to plan.

The result? Well, there could be some new impact craters on Mars in a few thousand years.

The DART mission was conceptually simple. Dimorphos and Didymos represent a binary asteroid pair with a known orbital period.

By smashing a spacecraft into the smaller asteroid, Dimorphos, and measuring the changes to its orbit, NASA learned that we have the means to deflect the path of an asteroid that may be on a dangerous trajectory toward Earth, so long as we have enough time to plan and execute the mission.

But Dimorphos isn’t a tightly bound chunk of rock. It’s what is known as a ‘rubble pile’ asteroid, relatively loosely bound together. Slamming into it with a spacecraft spewed a whole bunch of asteroid rock and dust out into space. It looked pretty spectacular, actually.

But what became of the rocks thus spewed? That’s what astronomers Marco Fenucci of the European Space Agency and Albino Carbognani of the National Institute for Astrophysics in Italy explore in a paper published in the Monthly Notices of the Royal Astronomical Society.

Their investigation focused on numerical simulations of the impact ejecta, 20,000 years into the future. They focused specifically on 37 boulders identified by the Hubble Space Telescope ranging in size from 4 to 7 meters (13 to 23 feet) across.

You’ll be relieved to know that Earth is going to be fine. Some of the boulders come close, but no cigar: they won’t approach near enough to pose a threat. But four of the boulders will come close enough to Mars that they could smack right into it – two in around 6,000 years, and two in 15,000 years.

And Mars isn’t protected by a nice atmospheric cushion like Earth is. Those rocks, according to the pair’s calculations, will fall straight down in one piece, excavating small craters up to 300 meters (984 feet) across.

Mars is pretty covered with space rocks and craters, so unless something dramatic happens in the next few thousand years, the impacts aren’t really going to rock anyone’s world.

But the findings do support the team’s previous work, which found that some meteorites that have slammed into Earth in the past are likely to have originated in asteroid collisions in the near-Earth environment.

Anyway, we’re really sorry, Mars. If you want to throw some rocks back at us in retaliation, we’re sure there are some scientists who won’t mind.

The research has been published in the Monthly Notices of the Royal Astronomical Society.