Spirit Sol 776

Eager Ashley has already planned out a cromulent 30m-plus-autonav drive for us. We never execute it, because it turns out we somehow all forgot to do the long-baseline stereo observations of McCool Hill, and the farther we are from the hill, the better that's going to work. We're all eager to move on -- it's not just Ashley, it's the whole engineering team, and (as it turns out) the science team too. They just discovered that there are these huge sort of rings of layers passing through McCool, of which Oberth and the other promontories are just the most obvious components.

But our exploration of the hills, once we get there, will go much better if we sacrifice a sol now to take the long-baseline observations first. So we have a long pre-SOWG discussion which basically ends up deciding to do the long-baseline drive. Instead of 30m, mostly toward McCool, we'll drive just 8m or so, all visodom.

It's a tedious discussion at times, but Alicia Vaughan (née Fallacaro) is upbeat. "Visitors are good," she remarks as we're standing at the elevator. "They remind you how cool this is!"

Scott Lever agrees. "I've been on lots of projects, and this one is the most fun. Voyager spent two or three years getting someplace and then you'd have two or three days of excitement; this is new stuff all the time. Plus, the team is fantastic -- heck, most of JPL is fantastic. Can you imagine being in the real world? You could be surrounded by idiots."

Ashley's RP-2, but she's on the cusp of starting as an RP-1; she just needs a little more experience. So I decide to be Mister Nice Guy and let her play RP-1 today. It turns out I haven't learned much about sitting back and letting the other person drive; I'm a control freak through and through. I just can't stand seeing it done wrong, you know? By which I mean, of course, not my way.

Well, something else for me to work on.

I get my turn to drive, though, when SOWG chair Albert Yen asks a power-related question at the CAM. "What's our final northerly tilt going to be?"

We hadn't looked at this particularly, because the solar energy maps showed that the whole region was pretty favorable. But to answer his question, I bring up RSVP, check the simulation, and -- oops. It says we're going to have about 5 degrees of southerly tilt, which is pretty bad.

We call a halt to the proceedings while we figure out what we need to change. Careful analysis shows that the magnitude of the predicted southerly tilt is likely bogus; the simulated rover is "settling" on some terrain that's obscured by a rock and is likely much flatter than the software thinks. Nevertheless, there really are a couple of rocks in that vicinity that could end up under the right side of the rover, giving us a southerly tilt. As it turns out, we've got some play in the distance we need to go for the stereo observations to work, and if we cut it by half a meter -- from 8 to 7.5 -- we'll nestle the right side of the vehicle smack between the two rocks, with 10 or 20cm to spare on either side.

With that problem under control, I wander across the hall to chat with Justin Maki before I leave. The other day, when we made it to the edge of Home Plate, we took a NCAM mosaic. The result looked sweet, running from the deck all the way up to McCool Hill -- but not quite to the summit. It was like an otherwise brilliant vacation photo that cuts off the top of your head. So before leaving Home Plate, we took a couple of extra NCAM images of the hill's summit, to fill in the picture. (As it happens, I was the one to argue for it at the SOWG meeting -- Justin's convinced they'd never have listened if he asked for it, but they did it even though I stressed that we didn't need it for drive purposes.) It's amazing what a difference it makes to have it -- the result is just terrific, well worth the two minutes and half-megabit or so it cost us.

"I bet this one will go up on the Web site," he muses. "The last time we did this, that image went up on the Web site. I think I figured something like two million people saw it. So if you look at it in terms of bits per visitor, it's a heck of a lot cheaper than most of the things we do."

[Next post: sol 779, March 13.]

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