Spirit Sol 63

I wake up feeling the usual absolute sick certainty that I've destroyed the rover. At the very least, I should have nudged the final waypoint a little to the southwest, to leave room for the final northeast-oriented "stutter-step" short leg of the drive; this portion is done using autonav, so the rover will keep itself safe, but they might miss out on some science data. I check the downlink reports two or three times before even leaving home, but in vain. The pass hasn't happened yet, so there's nothing to report.

Of course, everything went perfectly. The final part of the drive timed out, but that wasn't unexpected. We're now 88m from the crater rim.

So I worry too much.

Most of the scientists are off today, on a field trip to Amboy Crater (where they did some of the Sojourner field testing). Steve Collins suggests freaking them out by getting out there ahead of them and putting the testbed rover in the crater, drilling RAT holes in various rocks, and so on. "Fooled you!"

John Grant, who's back to being the SOWG chair again, spots me looking over the drive data with the Mobility/IDD folks. "You da man!" he tells me. Their tentative plan is to shoot for another 20-30m tomorrow, then maybe a megadrive toward Bonneville. We'll be maybe 10m from the rim at that point, almost close enough to reach out and touch it. With our robotic arm.

With the scientists on a field trip, the downlink assessment meeting is sparsely attended -- only about 20 people in the room, less than half the usual number. It's also much more informal and jocular than usual. Everybody can sit more or less within earshot of each other, so they don't really need the mikes, and the room takes on a much different dynamic.

The group's already bouyant mood is only helped along by LTP's welcome observation that we've now traversed about 250m of the 300m required for Spirit to claim full success; everything else NASA requires of us is done. ("Ah, let's just do the 50 meters tomorrow and finish it up," I suggest. In this crowd I find lots of approval.) For the near future, we'll be alternating "dirt sols" (examining soil or rocks, as we will tomorrow) with "aerosols" (studying the atmosphere).

It so happens that there's a smooth, long, flat rock just in front of our left wheel. They've named this rock "Plank," and the debate du jour is whether to IDD the rock or the soil -- or to skip it and just dedicate the day to driving. The case for IDDing the rock is strengthened if it's one of the so-called "white rocks" we've seen around us occasionally. The White Rock Mafia is all at Amboy, so nobody's here to argue vociferously for examining Plank (if it qualifies as a "white rock" at all), but a few of the scientists try to represent them in absentia. They end up deciding that Plank is not a white rock, but when the vote comes, the scientists decide that the rock is of more interest than the soil (by 11-3, a runaway). So we're going to try to IDD it if possible. (The conclusion was helped along by a great compromise idea from John Grant: whether we vote for the rock or the soil to be the favored target, also choose a backup target from the other area; if we can't reach the favored target for whatever reason, we'll do the other instead.)

John floats the idea of doing a megadrive on the following sol. Preliminary opinion favors this, but with some dissent. Some of the dissenters seem to be swayed by Jim Bell's observation that we want the sols leading up to the crater rim to minimize data generation, so that we can clear out the flash -- when we get up to the rim, we'll be taking picture after picture, of the crater and the surrounding terrain, and we'll need somewhere to put them. On the other hand, as Doug Ming points out, we're rushing through a rich target area right now; we have a responsibility to study the terrain systematically as we go, not just blow through it. John cuts off the discussion shortly after that, as they need to discuss it with the full group anyway, and I go off to see if the IDD can reach the targets they've chosen.

It can't. Or maybe it can, but this will take careful sequencing, and I'll have a lot of driving to plan as well as the IDD work. Doug Ming saves me by finding another target on the rock that turns out to be a snap to reach. This makes my life much, much easier. (I probably could have saved myself a lot of trouble on other sols by telling them that they should choose different targets, but I hate to push back on science. I need to consider the fact that it can be better for them if I do that sometimes. And usually they don't care about the particular target anyway; they just want measurements of the rock, not of this particular point on it. Live and learn.)

As a result, I'm done sequencing the IDD work by the end of the SOWG meeting (though Bob will tweak it later, as he always does). It's gratifying to realize how far I've come: doing a multi-sequence, three-instrument placement used to be at the limit of what I could handle in my shift. This one I get done in maybe half an hour, leaving plenty of time to work on the drive.

So I have plenty of time to check out the crater rim. Some of the scientists, looking carefully at today's post-drive PANCAMs, have noticed that you can just barely see the far rim of the crater. We're looking through a dip in the near side of the rim, seeing the inside of the Bonneville, on its far side. "I'm reminded, once in a while, of why we do this," Andy remarks.

Even before seeing the crater rim, Andy was in a good mood, possibly because this is his last day on Mars time. He's returning to a strategic shift (which means: normal Earthling-type hours) in order to help design the extended mission. Julie Townsend is going to take his place, after she finishes training her own replacement (Saina Ghandchi).

Those aren't the only personnel changes. Lots of people are leaving the project altogether, including, to my surprise, Rob Manning. He's going to work on some other project that needs him more. Pete Theisinger is long gone, of course. The rovers themselves are going strong, but the team is breaking up and fading away.

Courtesy NASA/JPL-Caltech. I believe this is the PANCAM image I was looking at, where you can just spot the far rim of Bonneville through a sort of notch in the near rim.

Courtesy NASA/JPL-Caltech. The long, flat rock next to the left front wheel is Plank.

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