NASA's Perseverance mission has been one of triumphs, but now the rover is facing a mystery worthy of an interplanetary Sherlock Holmes. A rock sample has gone missing.
The rover successfully made its first drill hole in a rock on Mars with the intention of collecting a small sample and stashing it into a tube. The tubes are meant to be picked up and returned to Earth by a future mission. On Friday, NASA said data indicates "no rock was collected during the initial sampling activity."
The sampling seemed to go as expected, but the autonomous process includes a probe check of the tube to measure how much rock is in it. "The probe did not encounter the expected resistance that would be there if a sample were inside the tube," said Perseverance surface mission manager Jessica Samuels.
The rover's Twitter account noted this sampling enigma is "something we've never seen in testing on Earth."
The rover team suspects Perseverance did everything right, but that the rock itself didn't behave as expected. NASA is continuing to analyze data and images to try to solve the mystery.
Perseverance landed in the Jezero Crater in February and its first sample was expected to be met with celebration rather than head-scratching. The crater was once home to a lake, making it a prime spot for the rover to seek out signs of ancient microbial life.
The sample attempt might not have worked out, but the wheeled explorer is equipped with 43 tubes, so the team will try again. Mars is full of surprises and the rover was bound to encounter a few hiccups as it travels across the red planet.
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