Spirit Sol 78

I get to thinking while driving in to work. We haven't screwed up many drives, but the ones where we've had the most trouble have been approaches. Traversing many meters in terrain where you'll slip an unknown amount, and having to end up in a zone only 10 or 20cm wide, is a recipe for failure. Even in this terrain, where we knew we were slipping 5-10%, given the length of the drive, the uncertainty in the amount of slip exceeds the size of the target zone. So we were, essentially, relying on luck. Gambling. And we lost.

The Mazatzal approach was just one example; we had a similar issue when approaching Humphrey, but it so happened that that drive was planned as a two-cycle drive for other reasons, so they had a chance to recover on the same sol. I decide that the next time we have an approach sol, I'm going to insist on either visual odometry (which we currently can't use because of the irreproducible problem we had with it on Opportunity) or a two-cycle drive. It might take some selling, but I'm determined. I don't want another drive to go wrong, and it's better to take our time on the approach sol and do the job properly than have to waste one more damn sol recovering.

The pass comes, and I'm relieved to see that we're just about exactly where we wanted to be. I guess I'd be another 5 or 10cm closer if I could, but we can still reach plenty of the rock face from here, including RATtable spots. It's not perfect, but we can do the work we need to do. Not what I was hoping for. But you know what? Fuck it. I decide to consider this a victory.

I look at the front HAZCAMs with Dave Des Marais and Craig Leff. "So, is this a 'white rock?'" Craig asks. Dave equivocates on that point, but adds that the politically correct term is "light-toned rock." "Yeah, but the phrase 'Light-Toned Rock Mafia' just doesn't have the same ring to it," I say.

Craig asks if the rock is reachable, and I tell him we should have good coverage on the lower half of the rock at least. They should plan to RAT. "Short drive, huh? Piece of cake," he says. If he only knew.

"Holy shit," says Craig, looking closer at the picture, "there's a huge crater right next to us! Did you know that?"[1]

Despite the fact that we're in a decent spot relative to the rock, I still feel kind of depressed about it. Finally I decide I'm just not going to feel that way: I decide that today is going to be a good day, damn it. The Buddhists say that if you put on the face of a tiger you gain the courage of a tiger, or something like that.

I like tigers.

At least I'm not the only one who ever screws up. For days now they've been trying to delete some unneeded on-board directories; the sequence will take about thirty minutes to run and needs to execute early in the morning, which cuts into the IDD work. For one reason or another, it keeps not happening. Today Art has to report at the downlink assessment meeting that it didn't happen again: they somehow forgot to uplink the sequence yestersol. So they'll need to do it again, and structure the IDD work accordingly. Is it bad to feel relieved by this, I wonder? It's not quite Schadenfreude, but it still doesn't feel like the right attitude to take. Well, I can't help it. It does make me feel better, a little. Maybe.

There seems to be growing support for truncating the crater traverse. LTP's presentation includes two positions from which we might leave, one of them relatively nearby, the other 100m along the rim. But we've got a lot of work to do at Mazatzal before we go. We'll spend the next sol or two inspecting the original, undisturbed surface of the rock in three separate locations. Then we'll brush those same three locations and IDD the result, then grind one or two spots and IDD the result of that. We'll be driving again by sol 82 or so, and we'll drive for maybe a week before we have to stop a while for the flight software patch upload.

As Ray observes, though, the patch is being delayed at a faster rate than we're approaching it. Mark Maimone has taken to calling it "Xeno's software upload." That's a reference to "Xeno's paradox," after the Greek philosopher, who said this: In order to cross a room, you first have to get halfway across the room. Then you have to cross half of the remaining distance. Then you have to cross half of that remaining distance, and so on. Ergo, you can never reach the other side of the room.

Incidentally, Xeno, never one to leave a good idea alone, formulated a related paradox, which in light of Ray's observation might be more appropriate. It starts the same way: In order to get across the room, you first have to get to the halfway point. But, Xeno points out, in order to get to the halfway point, you first have to get halfway to the halfway point. But first you have to make it halfway to that point, and so on. Not only can you not cross a room, Xeno concludes, you can't even get started.

For an ancient Greek, Xeno knew a lot about software development.

Alian Wang gives a short presentation titled "Attacking Mazatzal," in which she lays out a strategy for the science we should do here. My favorite part of the presentation (after its title) is where she argues, "If we want to do this rock and get some idea about its coating, we should do the lower part of the rock." Which is the part we can reach. Phew.

At the end of the meeting, Tom Economou introduces a new pair of visiting high school students -- part of the Athena Student Intern Program -- Brianna and Filadelfo. They're from a Chicago suburb (Wheaton), and since I went to nearby UIUC for grad school, I go introduce myself. It turns out that Brianna is going to UIUC in the fall. Clearly an intelligent young woman.

Also, their high school mascot is a tiger. Freaky ....

Word on the street (well, OK, in the SOWG meeting) is that as the project downsizes, they're going to keep anyone who wants to stay. This is good news; they'll have to drag me out of here kicking and screaming.

I set a new personal record, finishing the sequencing -- at least getting the sequences into deliverable shape -- before the end of the SOWG meeting. But I have to change it afterward, when the scientists change their minds about the targets they want to go to. They'd chosen three targets -- California, Arizona, and New York -- and they decide to scrap New York for a target in between Arizona and New York. They need a name for the target. "What's the name of a state halfway between Arizona and New York?" someone asks. In honor of our visiting students, I suggest Illinois, and the name sticks.

Changing the target doesn't change the sequence much, and I end up with plenty of time to spare. "You look underchallenged today," says Art. "It's a nice change of pace," I tell him.

Indeed, I could leave early, except that I want to stick around for Opportunity's second try at exiting Eagle Crater. About noon I go to the SMSA again. Much the same crowd is there, and today we're joined by an NPR reporter as well. I think Frank and the other Opportunity drivers are itching to drive, drive, drive. Frank says something about looking forward to trashing some of Spirit's records. Despite their achievements, I guess they feel they've been taking a back seat to us in that respect. "Scott's been cordial about it, but Chris needs to be schooled," he says with an evil grin. To my chagrin, Ashitey reminds him of the one time I wasn't so cordial. Ashitey and Bob were discussing which rover was likely to live longer, and I said Opportunity would definitely outlast us -- "I mean, you guys have hardly even been using your rover," I said. Oops.

This time the drive succeeds: our next picture from Opportunity shows it on level terrain. They're out! Frank breaks out a bottle of champagne he brought from home, but Jim Erickson interposes himself between Frank and the media guys. "Not on camera," he says, and Frank sneaks the bottle back into his bag. Which is weird -- they were fine with the champagne yesterday. Maybe they got some flack over it, or maybe there's different media here today.

Anyway, this little flap doesn't dampen anyone's spirits (so to speak) in the least. The pictures show a weird, gently rippled landscape extending as far as the rover's eye can see. There's one rock in view -- "Bounce Rock," which they hit when landing; bouncing off this rock is what knocked them into Eagle Crater.

"In a way, it's like you've got a whole new mission," I say. "MER-B part B, or something."

"Yeah, and we've already discovered water," Frank adds.

Courtesy NASA/JPL-Caltech. Much better this time. Not perfect. But much better.

Courtesy NASA/JPL-Caltech. This time, Opportunity's out!


[1] That still cracks me up. I miss working with Craig.

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