Wednesday, December 29 (sol 306) Perseverance successfully cored and extracted a sample from a Martian rock. Top-down data after sampling indicates that the core drilling of the rock that the science team dubbed Issole went well. However, while transferring the bit that contains the sample to the rover’s bit carousel (which stores the bits and passes the tubes to the tube processing hardware inside the rover), our sensors indicated an anomaly. The rover did what it was designed to do – stopping the caching process and calling home for further instructions.
It was not until the 6e Once in human history a sample has been taken from a rock on a planet other than Earth, so when we see something abnormal happening, we go slow. Here’s what we know so far and what we’re doing about it.
The anomaly occurred during “Coring Bit Dropoff”. This is when the drill bit, with its sample tube and the just cored sample tucked inside, is guided out of the hammer drill (at the end of the robotic arm) and into the drill carousel (which is located on the rover frame). When processing previous cored rock samples, the drill bit traveled 13.1 centimeters (5.15 inches) before the sensors began to register the type of resistance (drag) expected on first contact with the carousel structure. However, this time around, the sensor registered higher resistance than usual about 0.4 inch (1 centimeter) earlier than expected, and much higher resistance than expected during operation.
The team requested additional data and images to ensure a good understanding of the state post anomaly. Given that we are currently operating through a set of ‘Restricted Soils’ in which data latency restricts the type of activities we can perform on Mars, it took about a week to receive the additional diagnostic data needed to understand this. anomaly.
Armed with this data set, we sent a command to extract the drill bit and sample-filled tube from the drill bit carousel and detach the robotic arm from the drill bit carousel. During these activities, a series of material images were acquired.
The extraction took place yesterday (1/6) and the data was downlinked early this morning. These most recent top-down images confirm that inside the bit carousel there are a few pebble-sized pieces of debris. The team is convinced that these are fragments of the cored rock that fell out of the sample tube when removing the coring bit, and that they prevented the bit from sitting completely in it. the trephine carousel.
The designers of the bit carousel took into consideration the ability to continue to operate successfully with debris. However, this is the first time that we have done a debris removal and we want to take all the time necessary to ensure the exit of these stones in a controlled and orderly manner. We will continue to evaluate our data sets over the weekend.
This isn’t the first curve Mars throws at us – just the last. One thing we have found is that when the engineering challenge is hundreds of millions of miles away (Mars is currently 215 million miles from Earth), it’s worth taking your time and being thorough. We will do it here. So when we hit the unpaved Martian road again, the Perseverance sample collection is also ready to roll.