2009-11-20

Opportunity Sol 293 (Spirit Sol 314)

"This is an historic turning point in the Opportunity mission," declares Squyres. "Literally a turning point."

What he's referring to is the beginning of our egress from Endurance Crater. We spent weeks getting as close to Burns Cliff as we safely could, days taking pictures -- and now we'll spend weeks getting away again. But we're not just getting away from Burns Cliff, we're leaving the crater itself. Endurance Crater will soon be a thing of Opportunity's past. This is sure to make a lot of Opportunists happy, those who are sick of being in the damn crater already.

We're at the tip of a sort of narrow "safety peninsula," a rough triangle of driving-friendly rock surface pointed roughly at Burns Cliff. Uphill of us the slopes are too steep for driving, and downhill the sand is too soft. When you're between Scylla and Charybdis, you navigate carefully, and so it is with us. This first drive will be very modest: 3.6m backward, mostly in a very gentle uphill curve, then -- if the rover is sure it's right where we wanted it -- we turn a little bit downhill and drive another 3.6m.

Squyres is ready to make tracks. There won't be much more meaningful science until we egress, so the faster we can (safely) do that, the happier he and the rest of the science team will be. So, as he should, he pushes on whether we can safely extend this drive. I tell him I think it's a bad idea: due to the narrowness of this part of the path, we need to take baby steps. We've got maybe 50m between us and the bottom of our egress chute, and the conservative drive we've planned is already covering more of that in one sol than we'd planned. The original plan was to take about 18 sols to egress, averaging maybe 3m per sol; we'll double that on this drive.

He relents, but later he comes up with another idea. "Since you've got the rover testing its position at the midpoint of the drive, did you consider doing another extension in the same way?" Yeah, I tell him, I did consider it, but I didn't think of it until too late -- it would have torqued the plan too much.

"I wouldn't have liked it anyway," Ashitey says. This is in keeping with his reputation as a risk-averse RP.

"If we'd had John Wright here, we'd have done it," I quip.

It's too late to change the drive, and since Ashitey would object to our trying anyway, we leave it alone. 7.2m tomorrow, then -- if we're lucky. It'll be a good start.

Once we're out of the crater and back on the plains, we'll be covering a lot more distance than that. Ashitey points out something interesting: Cooper's eager to set a new single-sol distance record, but he's going on vacation for a month or so, right around the time we're planning to egress. Meaning the odds are that much better that one of the rest of us could set the record instead ....

[Next post: sol 317 (Opportunity sol 296), November 23.]

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