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NASA thinks it knows why that Mars rover rock sample went missing

Perseverance tried to extract a core sample from a rock, but Mars didn't play nice.

This drill hole was supposed to give the Perseverance rover its first rock sample.

NASA/JPL-Caltech
This story is part of Welcome to Mars, our series exploring the red planet.

Rocks don't just disappear into thin air. NASA's been puzzling over a Mars mystery ever since its Perseverance rover tried to collect its very first rock sample last week. When the rover checked for the sample inside the collection tube, it found nothing. Turns out the rock itself might be at fault.

The rover drilled into a promising-looking rock in Jezero Crater, an ancient lakebed. The sampling process seemed to work as expected. It was to be the first bit of rock stored by the rover for a return to Earth by a future mission.

NASA's been assessing the data and taking a closer look at the drill site to work out what happened and why the sample tube ended up empty. "It appears that the rock was not robust enough to produce a core," said Louise Jandura, chief engineer for sampling and caching, in a statement on Wednesday.

A composite image shows the drill hole where the Perseverance rover was attempting to grab its first sample to store in a tube. The borehole is just over 1 inch in diameter.

NASA/JPL-Caltech/MSSS

Images show powdery rock around the drill hole, suggesting the rock simply crumbled. "The material from the desired core is likely either in the bottom of the hole, in the cuttings pile, or some combination of both," Jandura said.

Perseverance is equipped with 43 sample tubes, so the loss of one rock isn't a blow to the mission. The rover is on its way to another sampling location where it will try again. The team expects to find a more sampling-friendly rock to collect.

The good news is Perseverance's sampling process seems to work just fine. One uncooperative rock won't slow the rover's science roll.

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