Collecting rock samples for return to Earth is a primary objective for the perseverance rover. So there was cause for concern when the last two attempts failed. Here's what happened on the third attempt on this episode of Mars Guy. In the past two episodes, I reported on two attempts by perseverance to collect what are probably core sediments deposited by an ancient river that flowed into Jezero crater. But if deposits like this aren't well cemented by other minerals, they don't turn into strong rocks. And that matters for a coring tool that wasn't designed for crumbly rocks. On the first attempt, most of the material fell out of the bit, and all of it fell out on the second attempt. Still, this outcrop could include bits of far-flung rocks and minerals, and maybe even organic matter, all washed in from a large watershed. A sample of it would be a nice scientific crab bag. So the team decided to try for a third time, but not on the same outcrop. It looks like they set their sights on other candidates about 50 meters away, but the view looking back changed the plan. Here's Mars Guy for scale. These beautiful exposures of layered outcrops weren't visible from the first location, time for perseverance to pull a U-turn. It drove back to these outcrops and positioned itself on this one. Normally, an abrating operation is done on an outcrop before coring, as in every other time before. But not this time. The very next saw, after perseverance straddle the outcrop, it deployed the arm for a brief inspection with the Watson camera, and then moved right on to the coring operation, insert lyric from Suffrage at City. So jumping right to coring is a surprise, and so is the fact that one of the wheels is not fully planted. The front wheel is perched on a rock, but apparently not enough of a concern to warrant repositioning. Then there's the placement of the drill on the outcrop, with the stabilizers just a few centimeters from the edge, which seems a bit dicey. It all adds up to a sense of urgency to get this job done. The actual coring operation went smoothly in the normal amount of time. As the drill tailings piled up, they tumbled over the edge, adding a very unnatural pile of sediment to the Mars created version below. There are a couple of moves at the end, designed to break off a core that might still be attached at the bottom, and then secured in the bit, whether or not a core is actually there. These moves, and every other part of the coring operation, happen without humans in the loop. It's all autonomous, as is this step, showing the coring bit to mass cam z. Surprisingly, this time the rock was solid enough to produce a core, which is clearly visible at the tip of the bit, secured via the off-axis rotation of the bit around the sample tube inside. I presented this clever eccentric design solution in the last episode. On the previous two attempts, there were humans in the loop on the next step, which is to extract the sample tube from the coring bit, and take pictures of the inside before sealing it. That interrupted a normally autonomous operation, which could have resulted in sealing an empty tube. Instead, the same tube was used for all three coring operations. Surprisingly, though, on this third one, the tube was put through all the steps without a go-ahead from Earth, including getting its hermetic seal. But the feral in the seal has not been fully pressed into the tube to permanently seal it. Maybe the team decided to make the call on this final step to avoid a surprise ending.