Spirit Sol 56

[This originally happened on 2004-02-29, but since that year was a leap year and this one isn't, I'm going to make my life simpler by posting this on 2009-02-28 instead, and sticking with the original dates starting with the next sol (on March 1). So you get two sols in one day. Happy bonus sol!]

It's a mess. Last night, after I left, the mission manager got paranoid about the drive. Specifically, the concern had to do with the fact that the drive had been broken into two sequences, one to drive back and another to drive forward. What if the backward drive never got uplinked correctly? Then the rover would ram the rock.

Now, I admit I didn't think of this objection, but I wouldn't have solved it the way they did. They could have merged the two sequences into one, or had the first sequence invoke the second (hence the second would not run without the first). Chris Leger later comes up with a third way: send the rover a command that ground-precludes driving, then clear that flag from the first sequence.

They didn't do any of those things. Instead, they redid the forward drive in hazard-avoidance-enabled mode.

But their target is a big rock. Which looms as a hazard in the rover's on-board navigation map. So it will think we're telling it to drive into a rock with hazard-avoidance mode on. When you do that, it thinks you're crazy. And it stays put.

The upside of having lots of other people look over your work is that they'll find problems you won't. They've done that lots of times, enough times to make this a small price to pay.

But ... damn it!

We at least got the RAT mosaic. We can already see it in the images, a Mickey Mouse head with indistinct upper ears -- their upper halves fade out, showing where the uneven rock face curves away.

We got something else, too, three big anomaly reports. It so happens that there's no way to make your command sequence conditional on whether the RAT contact switches have tripped, indicating a successful placement. So normally, we have to place the RAT, get an image of its placement, review that image on the ground, and decide whether to proceed. However, each go/no-go cycle costs us a sol, and we wanted to do three RATtings in a single sol. So Bob and Eric came up with a tricky set of commands that get the desired effect. Your sequence looks like this: you place the RAT, make sure the IDD is happy, then issue a command that happens to generate a fault when the contact switches are tripped. Then you check to see whether the fault occurred. If it did, that means the arm is actually OK but the switches are tripped -- which is what you want, so you clear the fault and go on.

It's a clever idea, but nobody considered that the arm was going to think it faulted out three times. Every time it faults out, it generates an anomaly report, and these chewed up a good chunk of our downlink. Oops. If the drive had completed, that would have really hurt us. As it is, our other screw-up masks this one.

I'm feeling bad about the drive screw-up. I can't decide whether it's my fault, or one of those things that sucks but just isn't anyone's fault in particular. I've been splitting sequences up to make life easier for the SIEs, but if I hadn't sequenced these two drives separately, the issue wouldn't even have come up. But now's not the time to worry about it -- maybe we can recover. We talk about whether we can build and uplink a short drive sequence. It wouldn't be difficult, but if we do this, we'll need to do it before Earthset. When will that happen? Andy looks at his watch and thinks. "Right about ... now," he says.


When I get to the downlink assessment meeting, the SOWG chair for the day, Ron Greeley, is telling the science team that the science plans have been aggressive lately and the uplink crews have been great about supporting them. "When things don't go well, don't rag on those guys -- it ain't fair." This is true, and a nice thing to say. Perversely, it also makes me feel worse: I'm not just disappointing the scientists, I'm disappointing very nice and fair-minded scientists. Can't they just be assholes?

There are still possible recovery strategies. Maybe tomorrow we could plan a short drive for the morning, then come in in the middle of the day, get the telemetry, quickly sequence the RAT grinding, and let the grind run in the afternoon. This would save us a sol over the naive plan, which does the bump-drive and the grind on two separate sols. If we can't get the grinding sequence done, then we're no worse off. I quickly volunteer to try it, aware that this means I'm volunteering for something like two hours' sleep tomorrow. If that's what it takes, that's what it takes.

But will it work? Do we have enough time? My first impulse is to say yes, we can do it, but Andy wisely gives me a half-hour or so to think it over. The lead RAT, Steve Gorevan, and I get together to talk about it, and when we think we know what it will take, we talk it over with Andy and Mark Adler. ("Just say no," Adler half-jokes the minute he sees our worried expressions.) Once we get the post-drive downlink data, it will take maybe half an hour to get the terrain meshes and other products. Then the RAT guys need to find a suitable target on the rock. Then I need to take the mesh and the target and write a sequence that does what they want. We need to simulate it, test it, review it. There's no way to do all of this in less than a couple of hours. Then we need to actually uplink the sequence, and the rover needs to carry it out. The RAT grinding itself takes four hours to do properly on a rock that's as hard as this one. So we're looking at needing to have six usable hours left in the sol, and that's optimistic. We probably won't have that much time, so they'll need to shorten the RAT grind, which is an idea nobody likes.

But it might work. So the four of us troop into the downlink assessment meeting, which is still going on. ("This is troubling ...." says one of the MTES PULs when she sees us.) "You have an answer!" says Greeley. "We have questions," I respond. We lay out the plan, with all of its caveats. They don't seem to like it. They want to MI the pre-grind area, and if I'm honest with myself, I have to say this will add complexity that's likely to push us over the limit of what we can do in the time available. I still want to say we can do it, but I do the smart thing and stop pushing. Greeley gently nixes the idea, and Arvidson concurs: "Do it right!"

So this will be a slow day. Or not. Steve and another RAT guy, Tom, point out that we'd have less trouble hitting targets on this rock if we maneuvered around a little so we were facing it dead on. From where we are (or, to the point, from where we will be when we complete the drive with a short bump tomorrow), the reachable face of the rock slopes away to our left, an awkward surface for us to try to reach. So now I have something to do: see whether we can get the rover a wee bit to the left, so the rock will be easier to poke at.

The more I investigate the idea, though, the less I like it. This rover can't just crab-walk; if you want to be half a meter to your left, you need to do multiple turns and back-and-forth drives. It's not that complex, but given how the last couple of sols have gone, I decide I'd prefer to stick with the devil we know. Targeting the rock won't be easy, but we know we can do it from where we'll end up.

While I'm looking into this, Sharon Laubach pops in to say hi. I was right, she is changing jobs. But I was wrong about which job. She's going to be a rover driver, probably for the extended mission. This is a good thing for us and makes her very happy, but I can't help asking whose shifts she expects to pick up. She's vague about it. Maybe she'll spell me for some of my shifts if I have to write some software to support extended ops, she suggests. I comically hunch over and hug the monitors possessively, and she laughs. But I wonder if this means I'm not going to be able to drive the rovers in the extended mission, or if my opportunities to do this will be reduced. I guess we'll see.

It's looking like there's no longer any hope of reaching Bonneville by sol 60, which was our plan before the scientists got distracted by the shiny new rock. But in all fairness, that's the nature of the tactical process: we're supposed to leave our plans flexible, so we can react to the changing landscape.

Andy manages to put a good face on our situation at the SOWG, pointing out that tomorrow we'll manage to get a full charge on our batteries -- we normally do this once per week anyway, and it's been 10 sols since we did it last. Speaking of recharging batteries, the RAT PUL looks exhausted -- they've all been working extra because both rovers are RATting at about the same time. Steve Gorevan asks if I need him for anything, and looks very relieved when I tell him no. He leaves to get some sleep.

The plan for tomorrow is very simple. We're used to constructing plans with lots of things happening at once -- doing remote sensing while the APXS integrates, for instance -- but tomorrow is pretty well serialized. Apparently, this is how our extended-mission plans will tend to look.

I don't have much to do, since tomorrow we're just doing a simple 55cm drive straight ahead. I finish the sequence in minutes and drift into the science talks, which are now being held after the SOWG instead of after the downlink assessment meeting (to give the scientists more time to prepare for the SOWG, I suppose). Today they're discussing the trench results. Jeff Johnson shows the MI trench images, comparing the top and wall of the trench with the floor. The APXS guy reports that the spectra of the floor and the wall are very similar to each other, which could indicate water-driven soil mixing.

The free ice cream is now gone. Andy seems to think this is a bad idea, pointing out that the ice cream was meant as a recognition that we were doing something a little extra -- by which he means living on Mars time. When the topic has come up in meetings, he habitually declares that "if the ice cream goes, we no longer have to work Mars time." I don't care about the ice cream and I love working on Mars time, so I don't say anything, but I'm sympathetic: working on Mars time does disrupt your life. Mark Adler seems to be on Andy's side: he's filed an ISA (roughly a system bug report) on the lack of ice cream in the freezer.

I'd go home early but I decide to stick around for the midnightly science talk. This gets delayed and delayed, but when it finally happens it's way cool. John Grant tells us why Opportunity is finding El Capitan so interesting: the short version is, multiple converging lines of evidence all point to the rock being formed in the presence of water, probably a standing body of water that covered a large area. This has broad implications: Mars as a whole must have been warmer, and must have had significantly greater air pressure, at some point in its past. The larger implication of that is that conditions were likely favorable for the existence of life.

They'll announce this to the world on Tuesday.

Courtesy NASA/JPL-Caltech. We've now drawn a Mickey-Mouse head on Humphrey, by brushing away light-colored dust in three spots to reveal the darker rock face beneath. Essentially, it's graffiti on Mars. I get paid for acts of interplanetary vandalism.

Spirit Sol 55

On my way in I find myself reflecting that driving the Mars rover has become almost routine. I should have known better. Today's plan is something we've never done before, a RAT mosaic. Even the RAT guys have never done this in their labs; we'll try it for the first time ever by trying it on Mars. I'm surprised at this, but one of the RAT guys explains it to me this way: "It's getting late in the mission, and they're letting us go nuts."

The idea is to use the RAT to brush the dust off of three spots located next to each other on the rock we just drove up to ("Humphrey," or "Humphreys," or "Humphries," depending on who's spelling it), which will give a nice broad area for the MTES to investigate. It will also look like Mickey Mouse.

When I come in there's no data yet from last night, and to make matters worse I'm a little late. I start off behind for the day and pretty much stay that way, which is not good because it's going to be a complex sol. The slide that describes it at the downlink assessment meeting calls it "Albert's Folly" -- after Albert Yen, who I suppose came up with the idea. It looks like this:

1. Do a short APXS on the unbrushed face, just enough to establish sulfur abundance.

2. MI series.

3. Close the APXS doors.

4. Do the RAT mosaic. (Place RAT, establish ~30N preload, brush surface, repeat.)

5. Stow the arm.

6. Back up 85cm.

7. PANCAM, NAVCAM, and MTES the brushed area.

8. Drive 85cm forward, back to where we started.

9. Take documentation images to establish a new terrain mesh for the next sol.

On the next sol, we'll deploy the arm and examine the brushed areas. We'll also grind the rock -- maybe in one of the brushed areas, maybe somewhere else; they haven't decided yet.

They argue about whether to APXS or MI first. The argument for doing the APXS first is that the APXS gathers better data when it's cold; heat makes their data noisy. The argument for MIing first is that they want to see the undisturbed surface. The APXS wins.

Another sign that it's getting late in the mission is that they break the naming rules. There are a couple of high school students visiting us -- I don't think they're part of the Red Rover program -- and the scientists name the three brushing targets after them and their teacher. Naming targets and features after people is supposed to be a no-no. I don't care what they name the things, but there's some griping about it from several of the scientists and engineers. I think breaking that rule is a mistake: once you've opened that door, everyone wants to go through.

Despite the complexity of their plan, I'm calm and ready, not stressed at all. I've handled worse than this. But it doesn't want to go well, because I'm just that little bit behind and can't catch up. It's one of those days when everyone needs to interrupt me for a "quick question." Nobody's wrong to do it, but the result is that I can't get any traction.

And then it gets worse. Because we got the downlink so late, we didn't have accurate terrain meshes to plan with, so we couldn't create accurate targets, so we couldn't do critical portions of the sequencing. By the time we get targets we can sequence with, it's very late, and it turns out that the targets are going to be unusually hard to reach.

Which makes me feel stupid. All along I've been telling people that yeah, the work is practically done already, we're just waiting for the targets and it will all be over. Now I'm warning them that we might have to start over and select alternates, and it's pretty damn late in the day to do that. I can't help but feel like Stuart Smalley: "This was not ... my best ... sol."

I end up finding ways to reach the targets, but it's slow going. So it's not done when Bob comes in, and I stick him with more work than I usually do: he'll finish the IDD sequencing, I'll take the drive. I apologize for leaving him so much IDD work, but Bob -- the IDD expert -- laughs and says, "Yeah, you know how much I hate that!" So it's okay.

Don't get me wrong, I still feel like a moron. But it's okay.

Courtesy NASA/JPL-Caltech. Humphrey dares us to IDD it.


Spirit Sol 54

Since this is the last day I'll have off in this cycle, I decide to sleep in a couple of extra hours, which does me a world of good. I don't go to work until 1PM -- and I might not have gone then, but for the Space Act award ceremony.[1]

It starts late, leaving me time to talk to Brian about Opportunity-land. Ironically, considering he was the lead rover driver on both Pathfinder and MER, he hasn't had a chance to drive the rover yet -- just his luck, all of his shifts so far have been IDDing. He seems more amused by this than anything else, which is a good thing. He'll get his chance.

I tell him how frustrated I was for a while, when it seemed I would never drive, but the megadrive eased the pressure. And it's nice to have set a couple of records, even if they're sure to be broken. When I tell him that I was the one who took us past Sojourner's total-distance record, he grins and says, "Right on!" But his wife, Lynne, perks up then and says, "Well, but you'll never be first." Okay, maybe, but even if we'd all like to be Neil Armstrong, there's no shame in being Buzz Aldrin.[2]

The award ceremony moves more quickly than I expected. They process us in groups, team by team. They read off your names, you go up on stage and smile as the cameraman takes a couple of pictures, and everyone claps as you go back to your seat. But there are a lot of teams getting awards this year (and one guy is in three of the award groups, oddly), so it still takes a while.

I spend a lot of the time chatting, sotto voce, with Carlos[3], whom I haven't seen in a while. He's the same, seeming really nervous around me. I tell him that I got one of these awards when I first worked here, for a project I didn't really have anything to do with -- and then cringe, realizing that he thinks I'm hinting that he doesn't deserve this, even though that's not what I meant at all. Ah, well. I promise to show him around the ops area sometime soon, maybe tomorrow. Even though he and I didn't get along as well as I'd have liked, his code is in there, plugging away, and he wants to see it in action as much as I would.

A lot of the award recipients aren't there, including half of our team. The presenter jokes that they're probably out spending the money, and later announces that next year they'll give out the checks with the awards, so that everyone will be sure to show up. Ordinarily, the Space Act awards are presented by the Lab director, Dr. Elachi, but this year one of the second-tier guys does it instead. So it doesn't bother me as much that I didn't particularly dress up.

I was just going to leave immediately after the ceremony, but I can't help myself. I go up to 264 for a quick fix. As it happens, both rovers had kind of a slow day, so there's not much new anyway. The managers are sitting in the sequencing room with me, discussing personnel reassignments, which deepens my suspicions that Sharon -- and maybe other people -- are moving up. Or, at least, moving around. I don't care anyway, as long as nobody gets my job away from me -- and they can pry it from my cold, dead etc.

[1] We were receiving a NASA award for developing RSVP.

[2] Or, in my case, Dave Scott. I worked out once that, depending on how you count, I was the seventh person ever to drive a Mars rover. The seventh man on the moon: Dave Scott.

[3] Carlos Balacuit worked on RoSE with me for a while.


Spirit Sol 53

I'm tired and grumpy. I should have slept in.

I just want to clear out some of my backlog of work and go home, but I can't even sit down before I'm interrupted. Alex Hayes is panicking because the initial conditions file for this sol seems to have the rover turned backward. It's keeping him from getting some shadow modeling done. I take him with me to go talk to the mobility folks, and we work it out (it turns out that the INCONS file is actually fine, it's just that the terrain mesh is misleading).

Just after I take care of that, I'm interrupted again. This time it's by Phil, a nice guy, one of the RAT PULs. He's working on Opportunity, where they're parked on a slope as they inspect El Capitan, and the spot they want to RAT is just slightly out of reach. He needs help figuring out how to use HyperDrive to do their analysis -- they need to figure out what spot they need to get the rover into. He first asks Chris, who decides that since I'm not on shift, I should be the guy to help.

Grr. I need to put a stop to that.[1]

Anyway, I talk with Phil about it for a while, then connect him with Jeng, who should be able to help him better than I can. This also leads to another distraction: when I take him over to Jeng, Mark shows me today's images.

But this is an OK distraction, as distractions go. I slap on the 3-D glasses and start taking a look around. It's very bumpy and rocky here, possibly tough going for the rover, but the feature that stands out for me immediately is a rock that looks, I swear, just like the Pope's hat.[2] In fact, it almost looks like the Pope got buried, standing up, on Mars. We have to explore this. Maybe dig up the poor guy.

I blow through a few hours' worth of work, but I'm still grumpy and my wrists are hurting. And this is, you know, my day off. So fuck it, I leave.

And as it happens, I run into John Wright at the Subway on my way home. Every time I try to leave, they keep pulling me back IN!

Courtesy NASA/JPL-Caltech. The "Pope hat" rock -- Humphrey -- is at the lower left of this image. We got much better images of it later, but this is probably the one I was looking at.


[1] Although I should say that this was perfectly reasonable behavior on Chris's part. He was properly prioritizing his own ability to focus on tactical issues, putting that ahead of other considerations. It just annoyed me because I was grumpy.

[2] Of course, the proper term for the Pope's hat is "miter," but I think "Pope hat" sounds much funnier.


Spirit Sol 52

First thing on my agenda -- literally, just a few minutes after waking up -- is the WBBB interview. I've begun preparing for interviews by writing down a list of points I can make when the opportunity arises. (This is something our media trainers suggested, but I had to discover the truth of it for myself -- it's my way.) I make the list before calling in, but turn out to need very little of it, which is fine. It's a short interview anyway, just five or ten minutes. And it goes better than last time, as they don't ask me about any sporting events I haven't heard of, like, you know, the Super Bowl. As usual, they're very nice to me, and reasonably fun to talk to.

Just as I arrived at the same moment as Chris Leger yesterday, I run into Alex Hayes today. Alex is one of the scientists -- one of the younger ones, a student of Squyres who's just gotten his Master's. He's going back for his Ph.D. after the mission, and with something like this in his background, I imagine he'll get in anywhere he wants. Alex is a classic New York or New Jersey native, loud and brash. I usually find this personality type difficult to deal with, and Alex was no exception at first, but I've come to like him.

Our conversation is interrupted by a cell phone call from Mark Maimone, who has good and bad news about the drive. The rover got nearly to its destination but, near the end, was spooked by a slight downslope it saw in front of it. The downslope is not really a hazard, but the rover thinks it is, and that problem has been known for a long time -- indeed, Mark has long had a software patch to fix it, but they don't want to upload it yet. Today that decision bit us, but not too badly. The rover was about 3m from its target when it stumbled onto the slope, decided it was a hazard, and wasted the rest of the drive time making short back-and-forth staggering motions, hunting a way around the perceived obstacle. There wasn't one. We still ended up near the drive target, and it was a record-setting distance in terms of wheel odometry, though my record still stands (for now) if you measure start-to-finish distance covered.

The news is actually a little worse than that, as Rob Manning reports at the downlink assessment meeting. (Incidentally, if I ever have to get bad news, I want Rob to be the one to deliver it: he's so inoffensive and funny. This isn't the first time I've seen him manage these situations, and as before, he leaves the scientists more amused than angry.) The rover's downlink data rates are sensitive to its final orientation, so we try to tell it to point in a good direction after the drive. This is important enough that we even check for time-of-day limits on the drive and clear them to give the rover a few extra minutes to establish the correct orientation. But when we wrote the commands to do that, we failed to consider the case where an individual waypoint command times out, only the case where the global time-of-day limit is reached. As a result, the error wasn't cleared, and the rover ended up facing in a suboptimal direction. We still got the comm pass, but we got a lot less data than we wanted.

Since it was his drive, Chris -- as much a perfectionist as I am, and that's saying something -- is very upset about this result, as I would be in his shoes. So I try to cheer him up, pointing out that we were within our 10% error budget (the scientists are just spoiled -- they've gotten accustomed to our perfection, I guess), and that this will bolster support for Mark's nav-code patch, which only yesterday seemed to have flagged. Chris doesn't look any happier. I stop trying.

The scientists discuss the implications of this outcome. They'll have to generate a little less data tomorrow, for one thing, and because there's more uncertainty than normal about the post-drive conditions, the MTES experimenters aren't sure that their post-drive experiment did what they wanted. (But Ray reminds them of something he's said before: "There's no bad data.")

At least we know what to do tomorrow: we'll finish the drive, this time in blind-driving mode, so the rover won't be spooked by the non-hazard.

The happy news is that we've now driven 182m of the 300m we need to cover for mission success. As it happens, this is measured by wheel odometry, so the staggering at the end of the drive counts, even though it didn't take us anywhere. (Theoretically, we could achieve mission success in this respect by just driving the rover back and forth over the same spot, in one-meter segments, until we racked up 300m on the wheels. Come to think of it, that's not so different from what Opportunity is doing, ha ha.)

Ray praises the scientists on yestersol's plan. Coming out of the SOWG, we were only modestly oversubscribed (a desirable state; it tends to help in making tradeoffs at the subsequent refinement step, because there's a pool of alternatives to choose from when you cut something). Afterward we discovered power problems, but we were able to come up with a useful plan because the science team had done a good job of setting priorities. We're becoming an energy-limited mission, he says, so good prioritization is only going to become more important. John Grant asks if there are any lessons we can learn from Opportunity, then -- they've been energy-limited from the start, thanks to a stuck switch on a heater. The answer is yes: they create flexible, modular plans, so that the pieces can be rearranged as needed when problems arise.

Just as Ray got used to the term "antepenultimate," now we have another: "preantepenultimate." Tomorrow's drive requires a preantepenultimate turn in order to get into the right orientation for communications. There are widespread chuckles every time Ray stumbles through the word, which he appears to have to think about afresh each time he says it.

We're not sure if it will be safe to IDD, and Ray rejects the idea of trying. Tomorrow, we're data-limited, so we should go with a simple plan, and that's what they agree on.

I decide to skip the SOWG to catch up on my work backlog. Art Thompson comes in as I sit down, and asks the question everyone asks me sooner or later: "Don't you have anything better to do with your life?" I think about it for half a second, and say, "Well, no -- is there something better to do with your life?" "Actually, I guess not," he muses. Art is mock-upset because tomorrow's drive will be so short. "They never let me drive!" he thunders. "Yesterday, they do, like, thirty meters. And then today I'm the TUL, and it's, 'Let's just drive a meter.'"

He's at least half-joking, but as to the other half ... well, I know how he feels. At least I got that out of my system somewhat when we did the megadrive. Art hasn't had the pleasure yet. Maybe he'll get a chance soon.

I spend my remaining time writing a Perl script that should save the SIEs many hours of repetitive work, and finish just as John arrives. Considering this to be a more or less perfect opportunity to go home, that's exactly what I do.


Spirit Sol 51

Today will be relatively easy. This is one of the days when my shift overlaps with Chris Leger's, and this time it's my turn to take it easy. As it happens, Chris and I arrive simultaneously, and talk some on the way in. He's a morning person and is hoping Mars time goes away eventually -- my very opposite.

As we exit the elevator, we run into Ray Arvidson, who says simply, "Eighteen meters!"

Cool! That means we got through the whole blind drive. It turns out to be even better news than that; we actually got a few steps of autonav, which added about 1.25m to the drive. The day's total distance was 18.86m, about twice what we'd been officially shooting for. Mark will be happy, since this will get him some memory statistics to play with; I'm happy, because we didn't just drive the rover, we drove the heck out of it.

Not everyone is as happy as I am. Bill Dias is depressed about yestersol's activity plan. In a desperate attempt to come in under the resource limits, they ended up cutting scientific observations that had real merit, and didn't consume much time or energy. He particularly laments cutting a MTES experiment that would have generated all of 5KB of data -- practically nothing at all. Part of the problem is that our system assigns simple numeric priorities to experiments, and we're supposed to cut things in priority order. This simplifies many decisions (and simplifies the code), but it also means that sometimes we'll cut ten lower-priority experiments for the sake of a single higher-priority experiment, even when that's not a good trade overall. Maybe a better way (I reflect) would have been to start with a fixed number of "points" -- say, 1000 points -- and allocate them to the different experiments however you like. The goal of the revised game would be to maximize the number of points in the final plan. Oh, well: this is one of those things we'll have to try next time.

The scientists are stunned by yesterday's performance, little thinking we'd cover this much ground. The main question at the downlink assessment meeting is (with apologies to the Rolling Stones): should we stay, or should we go now? The rocks visible from here are, morphologically speaking, nothing new. Everything on Mars is interesting, Ray points out, but we should drive! When we reach Middleground, we can explore the local area. Ray wants to reach the crater rim in time for the March 10 stand-down, when they'll upload new navigation software to the rover. There will be a lot to explore and remotely sense there. Ray is not especially subtle in appealing to the scientists' sense of competition with their Opportunity counterparts: "Because this crater rim view is going to be certainly better than Marsberries."

So Ray asks directly, do we stay or boogie? The consensus: boogie.

The usual poll on instrument health contains one point of concern: the PANCAM came dangerously close to overheating yestersol. The instrument's safe temperature limit is 70C, and it got up to 65C somehow. Even as the instrument PUL is reporting this, the explanation arrives: a heating sequence inadvertently was run twice. That would account for it, the PUL says dryly.

We got in-focus MI images! I've been very worried about this. Correct instrument placement is my responsibility, so I was very concerned by the out-of-focus images we initially got from the trench. But it looks like it's OK now. Apparently I wasn't the only one who was worried -- word of the new in-focus images prompts applause. Which is nice, but I'd rather have gotten it right the first time.

Ray is warming to the term "antepenultimate." "I promised I'd learn how to pronounce it ... 'antepenultimate' is now my favorite part of the drive sol," he says.

Tomorrow we'll touch-and-go, and we've long since decided that the "go" should take us to Middleground, which is about another 30m from our new location. So the only discussion is on what to do with the touch. The question is whether to MI only, or both MI and MB. But we've got a lot of ground to cover -- 30m will set a new record -- and the MB will cut too much into the drive. So no MB tomorrow.

There's some resistance to this decision, because they want to characterize the changes (if any) to soil and rock composition as we drive, and the MB is crucial to doing that. What other mechanisms are available? One person points out that we've shown that the MTES can effectively see through the dust, so we can do some of the work with remote sensing. Another question arises because there's a small rock in reach: should we MI the soil, or the rock?

Steve Squyres, who's hanging out with us for some reason, pops up with a suggestion: since we're trying to characterize the rock's composition, how about doing a RAT brush and a PANCAM of the resulting spot? I tell him that we've been told that, until further notice, all RAT activities require a ground go/no-go. The time delay resulting from this will make it impossible for us to drive. Squyres thinks requiring a go/no-go for the RAT this far into the mission is ridiculous, but the directive comes from higher up, so he can't override it. (But he leaves the meeting and talks the mission managers and the mechanical team into allowing a brush. By the time he returns, the discussion has moved on, but he's made it possible for us to do it that way next time.)

The discussion starts to trend against doing a touch-and-go at all. Maybe we should keep things simple and just have a pure driving sol. Ray takes a vote, and the touch-and-go wins, though there's more dissent than for most votes. Then Chris reports that there's only 76W-hr available for the drive, and this gives Ray an opening to try again. "I really don't see a compelling argument for a touch-and-go at this site, especially since it might jeopardize the drive." He asks for consensus, and gets agreement.

The atmospheres guys have a "special treat" for us, in Ray's words. They propose an unusual experiment, waking the rover up in the middle of the night to take a PANCAM image of the Earth. They have some scientific justification for this, but mainly it's for outreach. Pathfinder tried this but it didn't work for some reason, so we're going to give it a shot. If we're to do this, we should do it soon, because the Earth is slowly disappearing from the Martian sky: as seen from Mars, Earth is lower and lower in the sky each night, visible only in the early mornings. If the rover lives until next December, he says, we'll get it as an evening object. This is a joke: there's no hope of that. So, he says, we'd better get it now. It will be a sizable power hit to wake up the rover and warm it up enough to do this, but despite that, there are no objections.

Ron Li has been working on localization. After each drive, we take pictures looking back at the lander, and Ron uses this and other information to precisely reconstruct the rover's path. He shows one of the backward-looking NAVCAM images, on which he's overlaid bright yellow lines illustrating our path to the present position, as seen from a rover's-eye view. This is somehow very emotional, and a great source of pride. When we started, we had no idea whether we'd even land safely, much less crawl off the lander. Now here we are, a hundred meters from the lander and moving fast. Before long, the lander -- our cradle -- will simply disappear. We'll never see it again.

That meeting over, I run into Squyres. He's been scarce in Gusev lately -- all the good science is halfway around the planet in Meridiani, I guess. "What are you doing down here with us lesser mortals?" I kid him. He's trying to stay awake, as it turns out, to give a presentation at 8AM. I check my watch -- it's 7:30. He's really drooping, so I give him a jocular pep talk: "You're almost there! You can do it!" What's the presentation? It's for Firouz Naderi, the head of JPL's Mars Program Office. The purpose of the presentation: to justify an extended mission for the rovers. Well, good luck! I don't think there will be much resistance to the idea of funding an extended mission, but it's a form we have to go through. The scientists have to line up and say yes, the rovers are doing great science, keep it coming; then NASA can say, well, okay, if the scientists want it .... So Squyres is doing his part in the little dance.

Since I'm the shadow today, I start catching up on other things. When I'm the primary rover driver, I don't have time for much else, so requests accumulate. ("One of the pleasures of reading old letters is the knowledge that they need no answer," wrote the poet Byron. The same, sadly, cannot be said of email. Email is too often a source of bad news in the form of new work. Old email is worse, because it's work you've had to put off, and which has generally become more urgent.) I've taken to handling this stuff on my time off. A shadow shift, with much lighter responsibilities, gives me that much more time to get things done.

I start with something fun: making a list of proposed rover wakeup songs. In order to sell the songs, I accompany each one with a light-hearted reason why they should use it. The Red Hot Chili Peppers's cover of the Stevie Wonder song "Higher Ground," for instance, has enough energy to power a Mars rover all by itself -- and so I tell the mission managers. I don't have a lot of hope that any of the songs will be used, but putting the list together is fun anyway.

Most of the rest of the work is not fun, but it's all stuff that needs to get done. Adding automated checks of our sequences, to take pressure off of the RP-2. Creating a way to run RSVP with a single click on the toolbar. (Which would be a no-brainer, except that running an instance of RSVP kills the existing instance -- which means that the naive solution leaves you with a way to accidentally kill the running instance with a single click.) Writing up what we learned from the first attempt at doing a megadrive. Stuff like that.

I'm still working on it when John Wright shows up. Because there is not a surplus of machines in the sequencing room, I do this stuff at (what is supposed to be) his machine, which means I'm always in his way. He's very polite about it, but I've started trying to get out of his way earlier. Today he has a new tactic: he comes in and tells Chris (within my hearing) that he's here, is going up to his office, and will be back shortly. I decide to let this be a good tactic; I've logged out and ensconced myself in someone else's temporarily available workstation before he returns. I need to start thinking of things like that.

One of the items stacked up in my email is a request for another interview with WBBB, the Raleigh radio station I've been on a couple of times already. They want to do this interview live, which means no sleeping in for me tomorrow. I could just ignore it -- but I don't. They were nice to me.

A couple of hours later, the usual user of the workstation I've moved to needs it, so I log out of that one. All of the others are occupied, and my shift is almost over anyway. So I fiddle around for a few minutes, annoy Chris by suggesting sequencing changes he's already made, and go home.

Courtesy NASA/JPL-Caltech. In-focus images of the trench, including the impression made when we probed the side of the trench with the MB. Gorgeous!

Courtesy NASA/JPL-Caltech. Ron Li's traverse map, showing the zig-zag path we followed from the lander to our then-present spot.

Courtesy NASA/JPL-Caltech. Looking back at the trench, midway through yestersol's drive.


Spirit Sol 50

The MI images we took of the trench wall don't seem to be in focus, blast it. One entire series is now down and is definitely out of focus; only the last image, the one farthest from the trench wall, is nearly focused. The other series are incomplete, but we don't have any in-focus images yet, and we don't want to leave without getting some nice closeups of the trench wall. So we're going to take a last shot at it before we leave, retaking a few images of the same spots from a little farther out. We're not sure why the images are unfocused, but the IDD doesn't seem to be positioning itself in the exact desired position relative to the trench -- whether because of a problem in the IDD itself, or because the terrain meshes are inaccurate, or for some other reason. Still, we deliberately touched the wall yesterday when placing the MB, and the IDD can remember that position and use the known position for targeting the MI, at least on that spot. This gives us some hope that the new pictures will look better.

After we do that, we'll drive backward about a meter, MTES the trench, and move on. The only complication is that we're also being asked to take MI images of the capture and filter magnets. These magnets are located on the rover deck, at the base of the mast. Getting the IDD to place itself there is tricky, and not something I've done before. We have a canned sequence to do something similar, but not identical, and given the potential risks, I decide to warn them we'll need to do it in the testbed first. But Ray Arvidson puts the kibosh on the idea anyway, at least for tomorrow. It turns out that this qualifies as a first-time activity, and we have rules about those -- one of the rules being that you can't do a first-time activity and drive on the same sol. At least, not without ground confirmation that the first-time activity completed successfully, and this will cut significantly into our drive time. And Ray wants to drive.

So Ray plays bad cop. The guy who wants the experiment is pissed off, but Ray just tells him, quietly and flatly, that it's not going to happen tomorrow. It'll happen in a couple of days, when we get to our next target. This gives us time to test it in the testbed and makes sure we keep moving for now. The requester is mollified slightly, but still leaves in a huff. Ray is Ray, unperturbed.

While I'm working out the sequence we'll need to test, Bill Dias stops by to talk to me. He's grumpy about something, and I decide to lighten him up a little by teasing him, telling him that they should just put him in charge of the scientists. "I'm glad you feel that way," he drawls. "They should put me in charge of a lot of things." You have to know Bill to be sure, but it worked; he's relaxed.

At the downlink assessment meeting, LTP lays out the plan. Tomorrow will be a touch-and-go sol, with a short drive of about 10m. The following sol, we'll shoot for another 40-50m, to get us to our next target, a spot called Middleground. Middleground lies smack between the two locations the scientists are really interested in, Humphreys and Sandia; when we get there, they'll decide which of the two targets -- or both -- they want to examine more closely before continuing to Bonneville.

LTP also has a warning: we're putting more data into flash than we're taking out, and this trend obviously can't continue indefinitely. In the near future, we may have to cut science observations in order to give the rover a chance to clear out the backlog. We have to think of it like this: lower-priority science observations we take today might trump higher-priority science observations we'd like to do a couple of sols from now.

One science observation we did get yestersol was a series of images taken over the span of a couple of hours, showing the rover's shadow lengthening over the Martian ground. This was accompanied by MTES observations showing how the rover's shadow affects the surface temperatures, but the movie itself is a cool outreach product. Ray had been against this as a waste of time, but now admits to the experimenter, "It's good that you fought for that."

Another result is reported, this one from the APXS. The trench floor looks just like the surface to the APXS -- in other words, digging in the soil doesn't reveal a significantly changed composition. They're guessing the wall measurements will show the same results, but the results aren't in yet.

Our drives have a new wrinkle: an antepenultimate step. We've long had a pair of steps at the end, a penultimate and ultimate, which let us take end-of-drive images that ensure that it's safe to deploy the IDD. The rover can't see the area immediately under the IDD, so if we had only the ultimate images, we wouldn't be sure it was safe to unstow the arm. Instead, we stop at the penultimate position, take an image, then take another step forward to take the ultimate image; this leaves us with images showing not only where we ended up but also what's underneath us. And now we have a step before that -- the antepenultimate -- to MTES and PANCAM the IDD work volume, which can't be done from the penultimate position (it's not back far enough). Ray hates this, both because it complicates things and because he can't pronounce the word. He keeps pronouncing it "antIpenultimate" -- as if it meant "against the penultimate" -- instead of "antEpenultimate," meaning "before the penultimate." Every time he does this I want to correct him, but I manage to restrain myself.

This meeting has long been run with just a pair of hand mikes, which as I've said before influences how well it works. An interesting change today: Ray wears a throat mike, so he can talk whenever he wants, and they hand the other mikes around as before.

Nathalie Cabrol gives the scientists a similar talk to the one she gave in the SMSA yestersol, regarding the polygonal soil structures and what they might mean, and their connection to the trenching experiment. The polygonal structures hint at freeze-and-thaw cycles, she says, and looking in the trench may help to confirm or disconfirm this hypothesis. Freeze-and-thaw cycles tend (on Earth, at least) to result in a mixing of soil layers, so that's one thing we'll be seeking evidence of as we inspect the results from exploring our trench.

At the end of the meeting, one of the MTES guys shows a HyperDrive-produced shadow movie, illustrating what the shadowing will be like tomorrow, to help them plan out the timing for tomorrow's science observations. Ray is impressed by this and emphasizes the importance of using our modeling tools for these purposes.

The SOWG goes relatively smoothly again; once more, I get a decent amount of the sequencing done before the meeting ends. But I do discover some bad news: we don't have as much of the surrounding terrain model available as I thought. We have a wedge directly behind us, and good coverage in front (the planned drive direction), but nothing to either side. Normally, this would be fine, but today we have something new in front of us: a trench. I had planned to drive around the trench, but without knowing what's on our right and left, I can't safely do this. What's more, we can see just enough of what's on our left to know that it's almost certainly not safe to drive there. We could zoom around the trench to the right, but it's a four-hundred-million-dollar gamble, and I don't like the odds.

So I look at another option: just drive straight ahead, right over the trench. Why not? The trench is only about 6 or 7cm deep anyway, and not so broad that the wheels are likely to get stuck inside it. I model this in HyperDrive for a while, and slowly start to think it might work. HyperDrive lets you see the rover's own evaluation of the terrain, and the rover doesn't see the trench as an obstacle. Then again, the rover's terrain evaluation is intended mainly for rocks, and for those it performs superbly. It doesn't always do as well with slopes -- or holes.

And it's another one of those things I haven't done. I deliberate for a while, and convince myself that it's liable to work out just fine. To be on the safe side, I end up calling Jeff Biesiadecki on his newly acquired cell phone (waking him, poor fellow). He hasn't tried it either, but thinks it should be fine, and there's no more expert opinion than his. So I decide to go for it.

The IDD sequencing complete, I put together a roughly S-shaped candidate drive. This first backs away from the trench so we can MTES and PANCAM it, then goes straight ahead, over the trench, zigzags between some rocks to the north, then bears northeast toward Middleground. At the end of the drive, after our terrain mesh runs out, I place a waypoint at Middleground itself, so that the rover will drive there on autonav if it gets that far. The amount of drive time we have available keeps changing as they refine the plan, and I have no idea whether we'll get more than a couple of meters of driving, much less the 18m or so that I've planned out -- and we almost certainly won't even get started on that final waypoint -- but I figure I might as well plan the most aggressive drive I can. If the rover runs out of time, it will just stop wherever it ends up, and if it gets enough time, well, we might as well cover as much ground as possible. The stated goal of the drive is to take us 10m closer to Middleground, but the real goal -- I am told in semi-joking confidence -- is just to get 1cm away from the trench, so the scientists will stop poking at it, and drive on already. This, I'm fairly sure we can do.

Sharon Laubach is hanging around, looking bored. Opportunity has a very tight IDD maneuver planned today, one that's making everyone nervous. They're placing the APXS up against El Capitan, and the positioning just happens to put the side of the RAT right up against our forearm, with maybe 2mm of clearance. If the positioning uncertainty is too great, the maneuver will cause the turret to rotate just a tad too far, straining against the forearm itself, and this will likely fault out the sequence. (Frank asked me to look at it earlier, and I didn't like it any better than he did. The software says it's OK, but we're not so sure.) They've lost a couple of sols lately and really don't want to lose another, so Sharon has come downstairs to fetch Bob Bonitz, the foremost IDD expert, to take a look. But his shift hasn't started yet, so she's just zoning until he arrives.

"Hey, you want to help drive the rover?" I ask her. Sharon's the honorary ninth rover driver anyway -- might as well make her work for it. She accepts the invitation, and we look over the drive together until Bob arrives. The drive itself isn't all that complex, but I don't know how the rover will slip when driving over the trench (it's not just the hole itself I'm worried about, but also the loose soil that we dug out of it). So I keep refining and refining that part, adjusting the drive distances until the rover is clear to turn without falling back into the trench, placing a waypoint to force the rover to automatically correct for slip. I realize I've started to understand the rover's behavior at deeper levels than I used to, and this is helping me build up a decent bag of tricks. I also add a command to dump the navigation software's memory usage statistics, as Mark Maimone has requested. It won't do any good unless we get to the autonav, but it won't hurt.

The other person Sharon has been looking for shows up, so I promise her I'll send Bob up immediately when he arrives. She goes off to talk to Richard Cook. (Richard was recently made project manager when Pete moved on to MSL.)

When Bob shows up, I send him upstairs as promised. He doesn't return until hours later, with the news that he told them to go with an alternate sequence. He'd done a similar move in ATLO, and found that the IDD had even less clearance than the software is now showing. This, together with the positioning uncertainties we have to deal with anyway, convinced him the risk was too great.

He's also a little annoyed that they didn't just call him at home. "They had a few hours of margin, and I think they didn't want to wake you," I tell him. He shrugs and says, "Better they should wake me up than lose a sol. What's a little sleep?"

Bob tweaks the IDD sequence I'd written earlier (maneuvering in the trench is tricky, and he has some ideas on improvements) while I finish up the drive. At the walkthrough meeting, we come up with an idea: we should take a picture looking back at the trench after we drive over it. This has very little science value but will be a cool outreach product, so the idea wins. It's not fully clear whether we have management's approval, but we think it's a cool idea, and Ray thinks it's a cool idea, and the guy who would have to build the imaging sequence thinks it's a cool idea, so we just go ahead and do it. (As a safeguard, we make the image a low-priority data product, so that it won't push out any science.) I'm still not sure how far we'll slip, so I don't want to put this in the drive-over move itself -- if the rover gets stuck in the trench, the situation isn't going to get any better while it sits there for a full minute taking a picture. I want it to keep moving. So I add the command to take the picture from a little farther away; the picture likely won't be as cool, but we'll get it.

This has been a long day for me, I realize; because they pulled Bob away for several hours, I figured I should pick up some of his shift, and the result is that I've been here something like 14 hours. But working together, Bob and I get everything done, and only about 5 minutes late. Not too bad, I guess. I finish up the (electronic) paperwork for the drive sequence and go home.

Courtesy NASA/JPL-Caltech. Maneuvering the IDD in the trench -- tricky business.


Spirit Sol 49

The rover's batteries are fully charged, but mine aren't. I'm not sleeping enough. So it's particularly nice that I get to see a lunchtime science talk -- it was delayed for some reason today. Nathalie Cabrol tells us about the implications of the features we see in our trench, and why we've stopped here for a while instead of driving on (which she's comically apologetic about). For one thing, the hollow we've stopped by is the last one we can see between here and Bonneville, so if we're going to investigate those features, we'll have to do it now. As Dave Des Marais told me yestersol, the polygonal soil structures are another reason to explore here -- they're like the ones you see in parched desert soil, cracks caused when water and salts evaporate out of the soil, fracturing it. She's careful to emphasize that there are multiple possible explanations, but she's clearly excited about what she sees here. She's looking forward to the results of the MI images we'll be getting today as we continue exploring the trench. (Incidentally, Art Thompson, ever the instigator, remarked in yestersol's downlink report that Spirit's trench was "the best Martian trench ever." Of course, there's only been one other, and you know who dug that one ....)

After the talk, Frank asks me to look into a SEQGEN-related problem. It turns out to be yet another instance of the ridiculous comment problem. There are a couple of spacecraft commands which, if you add comment text to them in your sequence, trigger a SEQGEN bug. For some reason, this bug has multiple symptoms; I can't tell why you sometimes get one set of symptoms and sometimes another. Frank already knows about this problem and tried to remove all of the problematic comments, but he accidentally left a single space character behind on one of the commands, and that was enough to trigger the bug.


At least yestersol seems to have gone well -- as far as we can tell. The IDD is in the middle of a long MB integration, which is exactly where it should be at this point. A few hours hence, it will switch tools, stopping the MB and replacing it with the APXS, but this hasn't happened yet. We get some MI images from yesterday -- only one full-frame image so far, but it's a beautiful shot anyway.

Other images we got back, as it turns out later at the downlink assessment meeting, appear to be out of focus, but that's why we take a series of them. When you look at something underneath a microscope, you always have to turn the focus knob until whatever you're looking at is in focus. We clearly can't do that focusing interactively when the microscope is on Mars, with 20 minutes between when you turn the knob and when you see the result, so we take a different approach: we figure out in advance where the best-focus position is, and we take several images around that position -- some a little closer, some a little farther away, to compensate for positioning uncertainty. The images from the middle of a couple of yestersol's series are out of focus, but they expect that when we get back the outer images, they'll be focused.

And we'll be doing that again tomorrow. Oh, will we ever. Yestersol we did three MI series, a total of 21 images, and tomorrow we're doing 22 images. (This total of 43 images, incidentally, is a large number but is short of the 47 MI images Opportunity took of its trench. "We have to beat you at something," Frank says.) Plus, on both sols, we're using the MB and APXS as well. It's amazing that I've come to consider this an easy sol: at the start of the mission, I'd have been severely worried about this. Now it's almost a no-brainer. (Not that I'm complaining: with the sols we've been having lately, a couple of no-brainers are just what the doctor ordered.) Next sol, we drive again.

LTP reports that mission success is basically unchanged, but I learn something from the report: mission success is 600m of driving distance, not 1km as I had thought. Which means we're about a quarter of the way there.

There are a couple of very short science talks. I'm distracted, so I extract exactly one piece of information from the pair of talks: the darker side of the drifts are less dusty than the lighter side and display a weak olivine signature. Maybe that's two pieces of information.

After that I help the scientists plan tomorrow's MI targeting. They're trying to come up with names for targets that lie at the bottom of the reachable zone, a line that divides the part of the trench wall we can't reach from the part we can. They name one of the features DividingLine, which is painfully generic but they're in a hurry. They need one more name, and they take my suggestion: MasonDixon.

W00t! I named something on Mars!

The SOWG meeting goes surprisingly smoothly and is over in no time. Afterward, more than one person remarks that it was "the fastest SOWG ever." I attribute this to the fact that, at least in broad outlines, we're copying Opportunity here, and Ray Arvidson is determined that we shall do so. So there's not much argument; they can skip almost immediately to figuring out how much of their plan fits into the available resources. Most of it, it turns out.

As I did yesterday, I go ahead and start sequencing in this meeting. That's a lot easier on the rare sols like this one, when there's not much debate about what they're going to do, and they don't need me to help them much. I don't get far, but I don't need to, this being such a piece of cake. I'm done sequencing by the time Bob shows up, with only one IDD move I don't like -- at one point, the APXS comes uncomfortably close to scraping the material we dug out of the trench. Fixing this will give him something to do, so we hand off in record time -- earlier than ever, before the activity plan approval meeting even starts.

This leaves me with a little bit of time to gossip and chat. Bob Kanefsky voices a common lament, namely, that he never knows whether to say "Good morning" or "good night," and suggests "good sol" as a Martian replacement. The juiciest rumor is that the NASA Inspector General is coming. Apparently -- we have this on very good authority -- a bunch of Shuttle guys came out to learn about our flight ops approach, decided that our way should be the model for doing ops, and wrote a glowing report that they sent out to the directors of all of the NASA centers. (It says something that everyone who hears the story to this point is cringing in embarrassment, hiding their faces in their hands, and so on, but the story doesn't end there.) Apparently, the IG's office decided that we can't really be doing that well, and hence that we're probably doing something unlawful, and they've opened (or "are opening," which might mean it will never come to pass) an investigation. I can't fathom what they think we could possibly be doing wrong, or for that matter why NASA would be so suspicious of success. (That says a lot, too.)

Really, the project isn't doing anything wrong. Except for feeding us all that meth. It's hidden in the ice cream.

I also have time to deal with more SEQGEN problems, which is good because we have more. The server needs to be rebooted again (though, to be fair, this may not be a SEQGEN problem, it just shows up there), and apparently this also happened yesterday.

And I push forward on another front. One of the daily time sinks we kept dealing with was going through our sequence flow structure with the TULs and SIEs -- showing them which sequences we had, and which other sequences we call from our sequences. This has to get done, because the rover drivers' sequences often incorporate a large part of the day's plan. But it takes time and is distracting. So a few days ago I wrote a script to make the list for us, and today it occurs to me that I can just show the TULs and SIEs how to run the script for themselves. Today I show Kevin Talley, who's enthusiastic about it. Teach a man to fish, and you don't have to deal with him any more, that's my motto.

It's time for me to leave, and on my way out I remember about the midnightly science lecture, so I go back and wait around for that, reading Nicholas Nickleby on the Web while I wait. The science talk is again given by Larry Soderblom, who discusses El Capitan (the rock Opportunity has driven to; Larry shows us a beautiful 3-D mesh of it) and the Marsberry phenomenon. Larry says that the Marsberries, or blueberries, actually look more like Cocoa Puffs, and later he uses an analogy with a "thin candy shell." Seriously, he must be hungry.

Anyway, the prevailing theory is that the Marsberries aren't deposited on the surface (say, by rain nucleating around airborne volcanic ash -- think of prehistoric volcanic hailstones that became rock), they're formed in place somehow. There aren't many processes that would explain this that don't involve water, but then again there are questions about why we see olivine at all, when olivine is so readily eroded by water. I actually think of what I think is a good question and ask it: what exactly does olivine turn into in the presence of water, and whatever that is, do we see a lot of it around us? That might tell us whether there was water and it just didn't get around to eliminating all of the olivine, or whether something non-water-related happened instead. Larry looks surprised and says that's a good question and he'll look into it. Impressing Larry is not easy, so I feel absurdly proud of myself.

The Marsberries are also thought to be spread throughout the terrain (and within it, as we know from finding some in Opportunity's trench). As the wind erodes the surface, the Marsberries are left behind. I think about that for a second and ask another question. If that's true, I say, the Marsberries should be thicker on the surface than under it, since the surface Marsberries represent everything that used to be above the current level. (One other implication occurs to me now: you could use the same observation to figure out how much more volume there used to be above the present surface level, assuming Marsberries form, or are deposited, at a constant rate.) That's right, according to Larry, and it's one of the things they're going to be looking for as they continue exploring the crater.

Ah, this science thing isn't so hard after all.

This last bit doesn't fit anywhere, narratively speaking, but it's cool: Randy Lindemann knows all kinds of crazy stuff the rover can do. He describes using the rover to flip over a rock. You drive it over the rock so that the rock is between the two back wheels on one side. Then you drive all of the wheels backward except for that middle wheel, and as the middle wheel drags backward, its cleats catch the underside of the rock and flip it. If little Martian bugs crawl out, you win unlimited funding.


Spirit Sol 48

Yestersol we dug a hole. This is a pretty cool maneuver, a variation on the one I watched Jeff and Mark rehearsing in front of the NBC cameras a few weeks ago: the rover holds five wheels steady and spins the sixth, digging it down a little way into the soil. Then it turns in place a little way back and forth, packing down the soil on either end of the hole. Then it returns to its starting point and digs a little further. The result, as in our case, is a hole as wide as a wheel and as deep as we have patience to make. (In this case, that's about 6 or 7cm. Opportunity's hole, by contrast, was nearly 10cm deep, and they needed less than half as much energy to dig it. Which would tell me something about the differing soil composition between the two sites, if I were that kind of person.)

They decided to dig in this spot because when they got the images after the drive that took us here, they spotted polygonal structures in the soil that, on Earth, indicate water. "But we're on Mars," shrugs Dave Des Marais, who's filling me in, "so we'll see."

Now that they've dug the trench, the plan is to IDD it. This makes me nervous, since it means all kinds of new ways to screw up. Fortunately, Bob is going to be RP-2 tonight, and he knows the arm like, uh, the back of his hand. So I won't be able to screw up too badly, anyway.

The scientists are excited, and the downlink assessment meeting is fairly upbeat. LTP reports that Spirit has now covered 131.1m, and we've now explored the number of different locations (four) needed for minimum mission success. Also, our recent aggressive drives have brought us within "kissing distance" (as Dave phrases it) of the path that will take us to Bonneville by sol 60. We'll hang out by the trench a while first, spending a couple of sols here, then we're driving again.

Ray Arvidson has shown up for the meeting, partly because he's going to be the SOWG chair for a couple of sols starting tomorrow, and partly because there are specific observations he wants us to make at this trench. It's a rare chance for an interplanetary comparison, in which we'll do science observations that complement the ones Opportunity made at its trench. We'll also be prototyping drive science for the extended mission (and it's weird to me that they're already planning the extended mission; but here we are, past the halfway mark already).

The conclusion Ray pushes them to is to do a couple of long APXS and MB integrations on the trench, along with several MI observations. I suggest that they pick backup targets within the trench just in case their primary targets aren't reachable, which was a practice that saved us at Mimi and might do so here as well, since it's hard to safely maneuver the IDD in the trench.

They're going to have a lot of questions I won't be able to answer without using RSVP, so by the SOWG, I'm already sequencing. This works out perfectly; they keep asking me questions I've just gotten the answers to. At the end of the meeting, one of the MI guys comes over to ask if we're going to be able to put the MI on their preferred target, and I say, "Well, why not see for yourself?" And I show him an animation of the IDD doing exactly what he wants. ("You guys are so good at your jobs," he tells me and Art wonderingly. Apparently, this mission also has an unusually close rapport between the engineers and scientists -- I've never been on a mission before, so I don't really know, but he and Art talk about other projects they've been on in which the two groups were at each other's throats.)

Just to make my life more complicated, the RAT guys want another picture of the RAT magnets. Apparently there was something strange about the last picture they got, and they want to know if it was real or an image artifact. So I work out a position in the sequence where we can just flip the wrist a little bit and get them a nice shot of the magnets, and they're happy. As it turns out, we have a bunch of other imaging we need to call from our sequence, so this ends up fitting right in.

The handover to Bob goes more smoothly than usual. I finish writing up the handover documentation just as he arrives, and I manage to get the sequences into just about the perfect shape: close enough to finished to satisfy my persnickitude, but with a few tweaks still needed so he'll have something to do. This isn't going to get much better, so I decide to leave.

But right then the midnightly science talk starts, so I stay for that. This one is given by Larry Soderblom, who talks about what they found at Opportunity's trench. Opportunity landed in clean black sand, which is largely free from the sulfur and chlorine that glues Gusev's sand together. Over time, lighter sand has been blown out of the crater, leaving the sand we see -- and the ubiquitous Marsberries. (Which, as it turns out, are more nearly brown than blue in true-color images.) These Marsberries come in three types: the blue and spherical kind I've seen the most of; a yellow, gumdrop-shaped kind (which Larry calls "Kix"); and a third kind that are sandblasted, pitted, and darker in color (Larry calls these "grape-nuts" -- somebody's hungry). Opportunity's trench contained Marsberries, too, and while these are shiny like the ones on the surface, they lack the frosted appearance of the surface spherules -- possibly, this is simply because they're not on the surface, being rolled around and smacked with grit.

In addition, as Opportunity dug its trench, they confirmed their observations about its soil. It's like putting your hand in a bag of dry cement -- it retains a perfect imprint, showing that its particles are very fine.

Not long after the science talk finishes, I leave. On the way out I stop to pick up my mail, which I haven't done for weeks, and discover a letter from a kid in Long Island, addressed to me personally. I assume he got my name out of a newspaper or something, or maybe off the Web site. He asks me a couple of questions about the rovers, and encloses a couple of pictures he drew, and asks if he can have a poster of the rover. I think about when I was a kid his age, watching the Voyager missions on TV. About how much it meant to me to know that the world was so much bigger than the little town I lived in, that there was this huge universe out there, waiting for people to explore it. How I wanted to grow up to be one of those people. And here I am.

You bet you can have a poster, kid.


Spirit Sol 47

I get up, get ready, and go out to the car to go to work. Where I find that the driver's-side window has slipped out of the little rubber track that it's supposed to slide up and down in. So it won't completely roll up, which is a problem on a cold night like tonight. Not to mention that some asshole will steal the radio if we don't fix this ASAP.

I can see the problem, but I don't have the tools to get at the bits I need to get at in order to fix it. I fuck with it for half an hour or so anyway, getting my hands filthy as I slowly freeze. I eventually get so frustrated with it that I just give up.

Good thing I'm not on shift today, because now I have to stay home so that I can take the car to the fucking mechanic and pay them good money to put a piece of glass back in between two pieces of rubber. Nice engineering.

So, to sum up: sure, we can drive a car on another planet, but you'd better not try to roll down the window on your fucking Honda Civic.


Spirit Sol 46

They tried doing yestersol's drive in a new way: they picked a destination point and told the rover to go there in "blind waypoint" mode. In this mode, the rover keeps more careful track of its location than it does during a pure blind drive, but it doesn't do the full autonav thing either (monitoring the surrounding terrain for hazards and avoiding them). Only the very last part of the drive -- less than a meter or so out of the 20m total -- was done in the regular "blind" mode. Not only should the blind-waypoint approach be more accurate than pure blind driving (because it automatically corrects for slippage), it also turned out to be 17% faster. So when possible -- when the terrain is sufficiently benign, and our drive postconditions are sufficiently generous -- we'll probably do our "blind" drives that way from now on.

Not much else happens -- I don't stay very long. I get my pix fix, and at last I get around to teaching the MI PUL how to work out the terrain shadowing himself, so they won't have to ask me. And that's it.


Spirit Sol 45

Yestersol's drive worked! We covered 21m, easily more than the 17m we needed to beat Sojourner's total-distance record. This means we set three world (interplanetary?) records in two days: longest directed drive, longest one-sol drive, and greatest total distance. None of these records will last for long, which is as it should be. But if they published the Guinness Book today, I'd have three entries.

I've been too busy to look at any of the pretty pictures for almost a week, so I catch up all at once. We've gotten some fantastic results, including the astrobot picture, which I hadn't had a chance to examine closely until now. Opportunity keeps making interesting tracks in its crater, and has gotten a few peeks over the rim. Flat. When the scientists tire of the crater -- if the scientists tire of the crater -- they'll be able to drive for miles.

While I'm doing this, Marc Pack comes over and asks me for RoSE's source code. This seems odd, so I ask him why he wants it. "Because you're the best Java programmer I know, and I want to be the best Java programmer I can be," he answers. Uh-huh. I don't know what there is to dislike in this request, and maybe this is just bad paranoia on my part. I don't really know the guy; he's probably on the level. So I split the difference, showing him a few books I think are excellent guides to different parts of Java and telling him that if he has any specific questions, I'd be happy to walk through the relevant code with him. This sends him on his merry way, and I go back to catching up on pictures. I can't shake the suspicion that something is behind that, but I can't think what it could possibly be. Nothing. I'm too paranoid.[1]

I catch up on my email and on the plan for the day (another touch-and-go, driving 20m to a nearby depression).

It's nearly time for Candy to get up, so I go home to see her. We end up wasting the day shopping, which was really not what I wanted to do with my day off, but whatever. I buy a cool book on Renaissance art and sleep for ten hours. Fantastic.


[1] At the time, there was a bit of behind-the-scenes political business going on, which is what underlay my paranoia. But it was misplaced: I've gotten to know Marc since then, and he's a straight-up guy. But you notice how I don't even consider the possibility that someone might say a nice thing like that to me and mean it? Sigh.


Spirit Sol 44

Today's my day to come in early to support the megadrive. Between getting home late and needing to return early, I only had about four hours to sleep. And I slept for only half of that, waking early because I was stressed out about the sequence.

I listen to the radio in the shower. I hear a funny BMW commercial comparing BMWs to a Mars rover. Still, I know which one I'd rather drive.

We're also on the news: KNX reports on Opportunity's trench-digging, and on our attempt -- the one we'll make today -- to set a Martian distance record.

I arrive not long before 11:30 rover time, when the first data from the morning activities is scheduled to arrive. We end up getting MI images -- which confirms that the morning sequences ran to the end, or nearly so. Shortly after that, we get confirmation that we drove!

This alone means that a lot of things went right. If we drove, then the IDD sequences -- which were planned two days before, and which executed this morning before this morning's drive -- completed successfully, and the IDD stowed. Plus, at least some of the drive sequence obviously executed.

That's the good news. The less good news is that the autonav didn't happen, which means that the drive didn't run all the way to the end. This causes some consternation, until we deduce the cause. Apparently, we set the mobility time-of-day limit -- a kind of reverse alarm clock, which tells the rover when it's time to stop moving -- about 20 minutes too early. As a consequence, the rover stopped moving just at the end of the blind drive, as it was turning toward Bonneville. We got about 18m as it was, but if we hadn't messed up the time-of-day limit, we'd have driven another 5m, maybe further.

But as it is, we still made a lot of progress -- including the longest directed drive ever on Mars -- and the rover is alive and healthy. So we can do our afternoon drive, which will let us set another record -- the longest one-day drive -- if we do it right.

MIPL pops out a terrain mesh in no time. We check with the uplink team. We've got about 30 minutes before we need to start uplinking our sequences. "Ah, no problem," I tell them.

Because of a second mistake, we have no post-drive NAVCAM images. This leaves us with only the HAZCAMs, and therefore we can see well enough to drive only a few meters ahead. This limits our options, but sometimes that's a good thing. We don't have time to explore a lot of options anyway.

Mark and Chris and I find the cleanest path through the terrain we can see, and we prepare the sequences we need. We're done with about 10 minutes to spare, which is actually more margin than I was expecting. Just as I'm about to deliver the sequences, Mark reminds me that we need to clear the goal error that was set when the rover ran out of time; if we don't, Spirit will refuse to drive. "Yes, I was just on my way to do that," I say nonchalantly, scurrying back to my workstation.

Well, still, we have five minutes to spare. I hand the sequences over to the uplink team, and as they get to work, I spend the remaining time indulging my paranoia, checking things that I know perfectly well are just fine and don't need any checking. One of the things I check is a list of sequences that got uplinked this morning, to see if all of the megadrive-related sequences we need actually made it to the rover.

That's funny ... I don't see some of the sequences that were supposed to be there. I check the list a couple of times, sure that I must be overlooking something. But I'm not. Three sequences are missing.

The three missing sequences prepare the rover for its drive and clean up afterward. If they're not there, the rover will still execute the drive sequences we're about to send, but without preparing itself properly. I'm not sure what the results of that will be, but they won't be good.

I ask around, and indeed, those sequences are missing. At the very last minute, we locate them, prepare them, and send them up along with the drive sequence. Disaster averted.

"How did you notice that the sequences were missing?" Celina Garcia asks me. I explain that I'm ridiculously paranoid, and that my paranoia just gets worse every time something like this seems to justify it. "I'm still barely functional as a human being," I tell her, "but a few more cases like this and I won't be any more."

With the excitement over, there's nothing to do but wait. And wait.

One good result of arriving so early is that I'm there for the lunchtime science briefing. Today it's by one of the Atmospheric Science guys, Mike Smith, who is very funny. You have to have a sense of humor to be an atmospheric scientist on this mission; relatively speaking, they get no respect. But they take it all in stride, and Mike talks about the science they've been able to do, watching how the temperature changes at different levels of the atmosphere over time. In a few days they'll have a simultaneous observation with MGS -- we'll measure the atmosphere by looking up through it at the same time they do a measurement looking down, flying over us. This is very similar to the flyover we did with MEX early in the mission.

We've got a while before anything will change -- there's no new data yet, and the downlink assessment meeting hasn't happened. Now that I've relaxed a little, I realize that I'm hungry, and the reason why occurs to me. I've been so busy that I haven't eaten for more than a day. I go out and get chicken strips from Jack in the Box, which are not bad at all, assuming you're hungry enough.

I'm back just in time for the downlink assessment meeting. The top story is that the MTES checkout sequence -- the one that was running when Spirit had its anomaly, and which never completed -- has now been rerun, and completed successfully. This means we can do nighttime MTES science, which makes the atmospheric guys very happy.

LTP reports that we've traversed 59.3m, plus today's drive. (Opportunity has driven 35.3m.) This is good, but still a long way from minimum mission success, which is 600m between the rovers. We've got a lot of driving left to do. Tomorrow will likely be a touch-and-go, once more driving toward Bonneville. We'll likely continue in this vein for a while, alternating touch-and-go drives with megadrives.

The scientists also present an MI image showing the MB's imprint in the wheel tracks, a target called "Mimi Tracks 2." This is an image from sol 42, the day of the unusually complex IDD sequence. (Actually, I think the image was taken on the morning of sol 43, but whatever.) You can clearly see the imprint we left in the soil, even including a relief of the small depression at the tip of the MB. I'm very happy for the scientists, who say the image is "incredibly interesting" and will keep them busy for months, maybe years, analyzing the soil's physical properties. I'm also relieved: I almost gave up on this target, since it was in a tricky spot, almost impossible to reach, making the sequencing inordinately complex, and we were so pressed for time that evening already. But I stuck with it, and found a way to make it work. Mimi Tracks 2 was also their third choice -- they had picked two other soil targets which were not clearly reachable by all of the instruments they wanted to use, and Bob Deen suggested that they choose a target that we were more certain to be able to get. Good thing he did so; we might have lost a valuable science target if he hadn't noticed the problem.

Courtesy NASA/JPL-Caltech. The MI image of the target "Mimi Tracks 2," showing the effect of pressing the MB instrument's donut-shaped "nose" into Spirit's tracks.

The Odyssey pass is coming, so I go to the SMSA so I can be there when we get the data. The longest one-day drive on Mars so far is 24.382m (set, I think, by Chris Leger, just a few sols ago). When we get the data, we find that indeed we've beaten the record, driving over 27m today. Mark reports this as "a new otherworldly record," and Joel Krajewski offers his congratulations. Andy adds that tomorrow, we should beat Sojourner's total distance record -- 17m to go.

A lot went wrong today. We lost time from setting the mobility time-of-day limit too early, from failing to uplink sequences in the morning (so that we had to uplink them just before the drive, at a much lower rate, cutting significantly into our afternoon drive time), and from not having the mid-drive NAVCAMs, which kept us from planning a long blind drive in the afternoon. And a couple of other things, too. All put together, this kept us from getting the 50m we should have gotten.

But a lot went right. All of the mistakes were minor, and were mostly understood and corrected, and we tested the megadrive approach. We learned everything we needed to learn in order to do it right the next time. And we did set a new distance record. I call it a "mini-megadrive," and the term seems to catch on. Jennifer uses it later when reporting on the sol's activities to the scientists, and it gets a tension-defusing laugh.

Tomorrow will be a fairly routine touch-and-go. We'll explore the soil we happen to be sitting on top of, then drive more. Andy is the TUL for the evening, and in the SOWG, we both push for a longish drive so that we can break Sojourner's record. I'm surprised -- but pleasantly surprised -- to see Andy pushing for it as hard as he is. I assume he's not the TUL tomorrow and therefore wants to be involved in breaking the record as much as I do. He has to talk fast in order to make it happen -- when the scientists have cut tomorrow's science as far as they can and are on the brink of cutting part of the drive, Andy talks them into giving up the evening DTE comm session instead. It won't return much data, and it's only an hour or so before the UHF pass, he points out, and we'll get all the data in the UHF pass anyway. They buy it, and the drive is on.

The sequencing itself, which would have seemed dauntingly complex just a few days ago, now seems a doddle. It's in decent shape when I hand over to John -- early, for once -- and I can actually relax a little and listen to the midnightly science briefing. This one's on dunes, and it explains why they wanted measurements of both the crest and the trough of that dune-like thing we examined a few sols ago (seems like forever, now). They were trying to tell whether it was a dune or a ripple. The distinction depends on measurements of the particle sizes at the crest and trough of the bedform (the generic term): ripples have larger particles at the top and smaller particles at the bottom, while dunes' particles are too large to make it to the top. The conclusion: it was a ripple. Don't ask me the larger significance of this, because I don't know (though I'm sure there is one). To me, it just seems like a cool thing to know.

I stick around for a few hours after my shift, so that I can put together our next software delivery. This takes longer than it should (doesn't everything?), so that by the time I leave I've been there 18 hours on about two hours of sleep. I go home and sleep as long as I damn well please. It feels wonderful.


Spirit Sol 43

We did so much work yestersol, and hardly anything has happened yet. This is as expected, since most of the work was in overnight operations that haven't run yet -- or, rather, that hadn't run at the time we had our comm pass. But so far, the news is good.

Assuming our sequences run successfully, tomorrow will be a pure driving sol. When we get the images that show us where we are, we'll plan the longest drive we can, then come in tomorrow afternoon (rover time) for an afternoon "megadrive." In preparation for this, Chris Leger brings me up to speed on the architecture they've come up with. It isn't quite the way I would have done it, but it's perfectly cromulent. We'll uplink forty or so sequences tomorrow, then when we know which ones we want to use for the megadrive, we'll uplink a small bridge sequence to invoke the autonav and a real-time command to start the drive. The bridge sequence also needs to fiddle with the driving time-of-day limit, which has been a bit of an annoyance for us, but it'll be fine.

It falls to me to give the uplink team a briefing on this plan. So once I understand it myself, I go to the SMSA, strap on a headset, and explain it. (Which is needlessly hard to do -- I think my way of arranging things would have been clearer -- but then again, that's just me being an asshole. It's perfectly cromulent.) I discover once more that I can no longer have a meaningful technical conversation without recourse to a whiteboard. They raise one of the projection screens for me, showing the whiteboard behind it, and that helps a lot.

Unfortunately, this causes me to miss the downlink assessment meeting. They won't have much to talk about anyway -- or so I assume -- since most of yestersol's data hasn't arrived, and tomorrow will be almost exclusively a driving sol, with very little science if any.

The SOWG meeting bears this out. We really have just one science request, to image the area immediately in front of the rover just before the drive completes. Chris was already aware of this and has built it into the megadrive sequences, so I don't really need to do anything to support it.

Today's main activity is about 18m of carefully planned driving, in which we must thread our way through several nearby obstacles to get to a reasonably safe zone to start tomorrow's megadrive process. This wouldn't be too bad, but it takes time to get a terrain mesh from MIPL that we can use for the driving. We have one that gives good coverage of the area immediately around the rover, and one that has decent coverage of the mid-field, but nothing really good for more than 10m or so out, and nothing that combines the near and far fields in a single mesh. It takes time to work out exactly what we need, and that leaves less time than I'd like for the actual sequencing.

Still, I must be getting better at this, because by the time Bob shows up, I've worked out the terrain mesh issues and I've got a first cut at the drive: we back up a couple of meters, maneuver between a dune (which is not an obstacle but could cause us to slip, which would endanger the rover later in the drive) and a rock, and zigzag between a couple of other obstacles as we head northeast in the general direction of Bonneville. When we get to the edge of the terrain mesh, we turn the rover in Bonneville's direction and turn on the autonav. What's really unusual is that we have to sequence this whole thing before we know the rover's final state. If the overnight and morning sequences we planned yestersol -- which are running now -- don't complete successfully, the drive won't even happen, and we'll have another sol in this spot whether we like it or not. So we might be rushing for nothing. Nevertheless, we have no choice but to proceed.

Bob seems a little nervous about the complex drive. He's obviously more comfortable sequencing the IDD -- he should be, he wrote the software for it -- but he's game. I sympathize with his feelings, though; it's exactly how I felt about both driving and IDDing when we started.

We decide to try to learn from previous experience and hand over the sequencing to Bob earlier. This frees me to fix up some minor problems I noticed in the megadrive sequences, which we'll be using for the first time tomorrow. At some point I find myself in the zone, which hasn't happened for a while: I'm kicking out code like breathing. This feels good.

What with one thing and another, I end up staying well past the end of my shift -- again. This is a problem I need to solve. And I have to come in early tomorrow, almost 4 hours early -- 11:30 rover time, not 15:00 -- to do the megadrive. Despite all of this, I'm weirdly energetic and happy. It might be fatigue, or it might not.

And it's oddly comforting to know I'm not the only one who has a complex task to struggle with. Even though the day was supposed to be simple, the engineering requests and imaging science added up to make it a complicated day after all. During the handover, Kevin Talley asks despairingly, "Why does every sol have to be an intelligence test?" At least we're passing.


Spirit Sol 42

While I was sleeping, Art Thompson called a meeting to discuss the megadrive approach. Mark and Chris were awake and got the email, went to the meeting, and ended up changing the approach somewhat. They're writing scripts to autogenerate a large number of canned drive sequences, with blind-drive distances ranging from 0m to 25m at headings of 20 to 80 degrees (centered on Bonneville), and a family of autonav sequences that will take us in similar headings.

I'm a little put off by this at first -- not just because I had already decided inside of my own head that this side project was mine, but also because it's starting to look like Chris will get to do all the long drives, and I'll mostly get wimpy drives like the one we executed today (all of 20cm, not counting the turn-in-place -- bringing our total odometry to 59.5m). But it doesn't take me long to get over it. I don't have time to produce the megadrive building blocks anyway, so it's a good thing Chris and Mark can do it. And getting to drive the rover at all is cool. I don't need to drive 50m. 1cm would be cool, and I get to do longer drives than that every day.

I repeat this to myself until I start to believe it.

I can't do any useful work because we didn't get all of the post-drive HAZCAM images down yet, so I catch up on my email, which has stacked up terribly. I'm losing that battle. I take care of the worst of it, then go to the downlink assessment meeting.

Happily, there's a lot of praise for me and Bob, as we did the most complex sequencing to date last night. Jennifer Trosper, reporting to the scientists on yestersol's activities, says that we did a "fantastic job." The SOWG chair, John Grant, agrees: "I know yestersol's plan was really complex, and we're amazed at the work you guys are doing to put it all together." Jennifer repeats, "Yeah, the overnight team did a fantastic job. We were surprised it worked -- as we usually are."

They're a bit stymied by the lack of HAZCAM data as well, but they know roughly what they want to do. Mimi was the main target, and they might be interested in some soil targets as well. Mimi is that flaky rock that was off our front wheel until we turned to face it yestersol. It's not a terribly large rock, just 15cm wide, and the PANCAM shows that it's not spectrally unusual. But they're still interested in it as a possible sedimentary rock.

While we're waiting on the data we'll need for more complex planning, they show one of the MI results from yestersol. I'm not sure whether we're looking at the dune crest or the trough in this image, but whatever it is, it's full of tiny little round grains or pebbles. Smaller than Meridiani Marsberries, and with a different composition, but not entirely dissimilar in appearance. Nobody understands them yet.

Courtesy NASA/JPL-Caltech. Sol-41 microscopic image of the dune, showing it's covered with small round grains or pebbles.

John leads a short discussion about these results, and I observe something funny about his style. He'll pose a question, then walk over to his interlocutor to hand them the microphone -- and in form, it looks almost exactly like Donahue. Also like Donahue, John often is kind of tightly wound, but to his credit, I must say that he plainly recognizes this and tries to overcome it. And he never takes it out on the engineers, as far as I can tell -- on the contrary, with us he's always genuinely appreciative and complimentary.

While they're talking about this, we get the news that the front HAZCAM image is in, so we'll be able to IDD tomorrow. The plan, as yesterday, is to spend one day IDDing here, then move on. This is going to be even more complex than last night, as we're going to do several overnight observations leading to a morning touch-and-go.

In order to do any of this work, I need a terrain mesh. Because of the delay in getting our downlink data, I decide to head upstairs and ensure that MIPL is aware that they need to produce one for us. I haven't interacted much with MIPL before, so I need to spend a long time talking to them about their process before I can figure out (a) what I need, and (b) what I should ask for. I also need to talk to them about why the reachability maps they've produced seem to show that we can't place the IDD on the top of Mimi, even though it's obviously accessible. The scientists work from these reachability maps when deciding what instrument placements to request, and I'm worried that they're going to miss out on doing the science they want to do because of the misleading data.

We work out those problems, but it takes time for the software to chew through the data and produce new results. And you never know exactly what's going to come out -- if there's a problem, and you get the wrong result, they have to start over, waiting another 15 to 90 minutes (depending on the mesh complexity). I head to the SOWG with my fingers crossed. (The first mesh they produce, it turns out later, is a mess, but Bob and Payam work hard on it for me, and we end up with a really nice product that's exactly what I need. And I learn a lot in the process.)

The headline at the SOWG is a rumor that the free ice cream will be terminated at the end of February. It's not clear whether money is the reason (much less that the rumor is true in the first place), but they're apparently spending $3000 per week on the ice cream.

That's a lot of ice cream.

While MIPL chews on the terrain mesh, we chew on tomorrow's plan. As expected, it's the most complex one we've ever attempted: a series of five sequences placing each of three instruments on two targets, including three overnight tool changes (two of which require careful attention to heating). One of the targets is Mimi, the other is our own wheel tracks, which are not normally in the IDD work volume (but they are this time because of yestersol's turn-in-place) and which will tell us something about the physical properties of the soil. I race to implement all of this before John shows up as RP-2, and do a reasonable job of it. As usual, though, there are a lot of niggling little details that require attention, and though I work on it well past the end of my shift, eventually I hand it over to him. It's in decent shape by then.

Even so, when I do leave, I feel as though I'm leaving John in the lurch. On the way home, I reflect on some ways I can do my job better. I'm a perfectionist, and that's really working against me here. I can't stand to give something I've been working on to someone else unless it's perfect; I hate saying, "Well, this is broken, and now it's your problem." But that leads me to delay handing off the sequences to the RP-2 (second-shift rover planner), which makes their jobs harder. My job isn't to get the sequences perfect, it's to get a decent first draft in place for the RP-2. Maybe if I think of it that way, it will neutralize my perfectionism. Also, maybe pigs will fly.