Spirit Sol 852

Retract the APXS and swing the IDD away for imaging, then return and place the MB where the APXS was. Simple enough; we could do it in our sleep. But this is the third try, the first two having been frustrated by random uplink failures -- nobody's fault either time, just plain bad luck.

Theoretically, we just have to roll the sequence forward to thisol and deliver it, and we're done. But Chris and I can't help thinking up better ways to do it, and in the end we pretty much rewrite the whole thing.

Al Herrera notices the activity and perks up. "You guys just changing the sol number?"

"Nope," I admit, "we had five minutes, and thought of something else."

"Not surprised," he chuckles, and returns his attention to his laptop.

Well, the new way is better, it really is. Can I help it if Chris and I are perfectionists?

[Next post: sol 857 (Opportunity sol 836), June 1.]


Spirit Sol 842

Meanwhile, back on the other side of the planet ... Spirit's been working on this lengthy IDD campaign on the soil in front of her. The other day, they tried to RAT-brush the soil (yes, really), but instead of the RAT hovering over the soil as they brushed, they apparently actually made contact.

We don't like it when stuff like that happens: the ground should be where we think it is, damn it. So today we're doing a bit of an engineering experiment, touching the soil, putting the RAT into the hover position, taking lots of images as we go. Science-free.

Since the mission started, there's been a bit of a friendly rivalry between the two rovers, particularly when it comes to total odometry. At times, Spirit's been ahead, and at other times, Opportunity's been out in front. Now, with Spirit not driving at all for six months -- and probably never driving long distances again -- Opportunity is poised to take the crown for good. As if to rub this in, Brian Cooper came downstairs and taped to the rover drivers' workstation a fortune cookie fortune he got just the other day:


[Next post: sol 852, May 27.]


Opportunity Sol 814 (Spirit Sol 835)

When I walk into the SOWG room, I'm startled to see Steve Squyres sitting there. Turns out he's out here so he and John Callas can meet with the NASA bigwigs about another round of funding for the mission. I wish him well, of course, and I ask, "Is it going to be harder now that Spirit's down a wheel?"

"The Spirit site is awesome!" Steve exclaims. "There's a whole class of science you can only do sitting in one place, and we've never done it at the Gusev site. No, no, we've got a great story to tell. It's just that there's only so much money to go around." And they might cut one of the rovers in order to save that money. Ulp.

He also tells me Rob Sullivan was thrilled with the MIs we took yesterday. "Rob was really, really psyched when those MIs came down -- you shoulda been there." Which is always nice to hear. Rob's a super-nice guy, and I like it when he's happy with the science we get for him.

The SOWG is over in 13 minutes -- shorter than an engineering keepout, as somebody points out -- and we're off. As we're wrapping up, everyone takes a moment to wish Steve good luck.

But Brenda's not worried. "If Steve Squyres can't get people excited about Mars, then the world is coming to an end."

"That's not the issue," Steve says modestly. "The blood's running ankle-deep at headquarters."

"Yeah," Matt Keuneke chimes in, "they'll be like, 'No funding unless you find a dinosaur bone.' And then they'll probably ask, 'How big is the bone?'"

Well, that's reassuring.

After the usual back-and-forth with Tim Parker and Matt Golombek, Paolo and I plan a 52m drive, including the autonav chunk at the end. Quite respectable progress, if it works out.

As we're wrapping up, Steve returns from the long meeting with the money men. "I went in thinking they're thinking the easy thing to do is to cut Spirit. So I hit Spirit so hard, one of the scientists asked whether we should shut down Opportunity." He grins wickedly. "Then I showed 'em Victoria Crater."

He sighs. "I expect there will be belt-tightening and cuts, but I expect we will have two rovers for the next year and a half."

That funding will have to come from somewhere, and it might end up coming from one of the other Mars missions. Steve offers his opinions on where that cut should be, should it absolutely have to be made. "If it were up to me and I had to cut one, I'd cut the U.S. participation in Mars Express. MEX can live without us. Then I'd cut MGS. MGS is not that great, with just the one camera working -- Odyssey can do everything MGS can, plus -- but MGS is doing great science and MOC is a great camera, and it would be a shame to lose any of it."

[Next post: sol 842, May 17.]


Opportunity Sol 811 (Spirit Sol 832)

At the end of the SOWG meeting, I point out to the whole team what I was able to mention to only a few people yesterday: that we're now up to sol 810 on Opportunity, fully nine times our nominal mission. And there is much rejoicing -- applause and cheers on the audio net.

The drive went beautifully, just perfect. We're perched on the side of the ripple just as we'd hoped. Only problem: there's no visible banding.

Well, it's barely visible if you stretch the images juuust right. But apparently this is something that disappears up close; it's a lot more visible if you look off to either side, along the ripple. That's a weird effect. It's plainly some sort of optical illusion, but I have no idea what causes it.

The bad thing about being perched on the ripple like this is that we took an energy hit, our available energy dropping from somewhere around 440 W-hr to about 386 W-hr, due, apparently, to the 10 degrees of unfavorable tilt we picked up.

Anyway, we're here, and we're going to IDD this thing. While Jeng plans the drive -- a surprisingly aggressive 40 meters -- I work out the IDD sequence. It's unusual for an IDD sequence, a 1x10 mosaic -- basically a vertical column of images all the way down the face. Since the local ripple surface is so uniform, the sequence ends up being nice and clean; I'm quite proud of it. And I hope it works.

[Next post: sol 835 (Opportunity sol 814), May 9.]


Opportunity Sol 810 (Spirit Sol 831)

I wasn't on shift yestersol, Paolo and Matt were, but they called in me and Jeng to give them some advice on driving in an area where we lacked good imaging. Our advice was to suck it up and use autonav. They did, reluctantly -- but it turned out that autonav got us within about 50cm of where we wanted to go, plenty close enough, and we're ready for more.

(Incidentally, when was the first time we had two RPs on shift neither of whom was from the original set? (I tend to think of Jeng and Ashitey as originals, though strictly speaking they weren't.) It wasn't yesterday, surely, but I don't know when it was. Ah, I'm such an old-timer now.)

But we're not going to charge down the trench, going for distance. Instead, we're going to try to address a question that the scientists have been kicking around for a while: what causes the banding we're seeing on these ripples? It looks as though there are several sets of ripples, one atop another, with slightly different albedos -- and what would cause that?

To try to find out, we're going to drive up on one and plant the MI on it. That's a slightly scary and just plain odd thing to do; we normally try to avoid these ripples, not climb them. But it's all for science, you know. So it's game on.

I'm RP-1, and Matt's shadowing me today. Since he's come up to speed on the driving (so to speak) impressively fast, I decide to hand him the reins and see how he does as RP-1. The short version is that he does great, planning a very nice approach where we scoot about 17m down the trench, then turn and charge right up onto the ripple. There's a bit of concern about whether we're going to hit the ripple in our post-drive IDD deploy, but then we realize that the ripple's only about 21cm tall, so the IDD would stay completely above it even if we were buried up to our wheels in the thing.

To make things more complex, though, we have very strict limits on our comm headings. If we're about 3 degrees off one way, we'll get a paltry 23 kilobits -- that's kilobits -- and if we're about 3 degrees off the other way, we'll be at a heading where the PMA will prevent us from talking to Earth at all, so we'll get nothing. Fortunately, ripples are broad, and we should be able to hit it spot on.

Though outwardly cool, Matt confesses he's not completely confident -- "I'm not gonna sleep tonight," as he puts it -- and while that's a feeling I know well, I have a lot of optimism about this drive. As long as we don't end up stuck in the ripple, and we've taken good precautions against that, it should be like hitting the broad side of a barn.

Should be. At least, that's what I'll tell myself when I'm trying to sleep tonight.

It's not until we've wrapped up for the sol, and I'm back in the office talking to someone, that I realize we overlooked something important. I literally run back upstairs to the Opportunity sequencing room, hoping other people will still be there.

Luckily for me, there are several people who haven't left yet, so there's someone to tell. "We just planned sol 810!" I exclaim. "That's nine times the nominal mission! How did we miss that?"


Opportunity Sol 807 (Spirit Sol 828)

We don't have much drive time thisol, so it's going to be a short one. We'll retract the IDD, then drive about 30m across one ripple and up to the next (almost nonexistent) one before we'll more or less run out of time.

And that's how we'll start down the Goodnight-Loving trail. No, I am not making that name up: it's the actual name of an Old West cattle trail, in keeping with our practice of naming our Victoria-bound drives in that fashion. But I can't help getting the adolescent giggles over this name, and I make a couple of jokes about it in the uplink report. ("And finally, on behalf of all the rover planners, I'd like to welcome all of y'all to the Good Night Lovin' trail. Oh, yeah." It's funnier when you read it like Barry White.)

[Next post: sol 831 (Opportunity sol 810), May 5.]