Opportunity Sol 401 (Spirit Sol 422)

Four hundred sols, baby. That's what I'm talking about!

The drive to Vostok went damn near perfectly, which apparently means the curse is lifted. As we suspected from the previous images, Vostok is large but very shallow, kind of like Shaquille O'Neal. (Just kidding, Shaq!) Over the millennia, the crater has almost completely filled with dust and soil. Now, only a broad ring of broken stone, like a circular garden path tens of meters across, shows where a meteor struck once, untold ages ago. At least some of Mars's ancient wounds have healed.

Frank and Brian spent yesterday starting on some IDDing of outcrop that ended up right under us, just as we were hoping. We'll likely continue that work over the next several days.

That's what we're doing today, for example. We're planning two sols today and another two tomorrow, so that we won't have to work Saturday. I think this is a great approach (heck, I advocated it myself yesterday), but it so happens that the two most complex sols out of those four are the two we're planning today. Well, if the work weren't difficult, they could find someone cheaper than I to do it.

What makes the sols complex is that we're RATting on both of them. I haven't done this for a while and had almost forgotten how much there is to it. RATting is usually part of a broad campaign that involves complex placements with all of the instruments, and this time's no exception, so the sol keeps me hopping.

It does give me a chance to play with a new flight software feature that tests directly for RAT contact with the terrain. It's a vast improvement over the old way we had to do it, which required deliberately generating a fault and some tricky logic to determine the cause of the fault and conditionally clear it. So this is good.

But the large workload and short timescale (it would be a tight sol even if we were planning only one) has a predictable effect: I revert to get-the-fuck-out-of-my-way mode, in which I trade politeness for efficiency. (Ahem.) I've been trying not to do this, but old habits die hard, and I have to admit this one is damned effective. Andy's already worried that he's been scheduling me for too many shifts, so he asks later, "Are you okay? You seemed a little testy earlier." I hope my reassurance suffices, because I want him to schedule me more! More! MORE!

Uh, anyway. What with all the work, I miss my chance to appear in an IMAX movie[1] they're filming downstairs; among other things, they're attempting to re-create the landing and egress. But it's probably just as well: the world doesn't need to see my face on a screen the size of a city block. On a screen the size of a thimble, maybe that's something the world needs to see. But a screen the size of a city block, forget about it.

Tomorrow would be simpler than today no matter what, but once today's in the bag (with an hour to spare, mind you; maybe I really don't need to be such a jackass), Khaled and I get to work on tomorrow's sequences. Khaled hasn't built IDD sequences from scratch yet, and doing it with no time pressure is the right way to do it. He's come along really well, and is turning into a fine rover planner.

But he can't have any of my shifts. More. More! MORE!

Courtesy NASA/JPL-Caltech; mosaic image hosted at Wikipedia. This is the entire 360-degree NAVCAM panorama, including (centrally) the broad ring of outcrop outlining what's left of Vostok Crater.


[1] This, of course, was Roving Mars.


g said...

Four hundred sols? Meh. What are your plans for four thousand sols?

Anonymous said...

I found Opportunity's rate of progress around SOL 400 amazing. I have heard rumours that Opportunity will soon reach easy driving country again. If so then will we be at Endeavour crater sooner than we all expect?

Scott Maxwell said...

@Anonymous We will indeed reach a nice flat zone in another kilometer or so. Once we're there, the terrain will again support longer drives, and we're looking into techniques to do those safely with the current hardware.

But what's currently constraining our progress is less the terrain and more the condition of the right front wheel: we're sticking to 70m/sol as a way to keep that wheel healthy, and if in fact we need to continue to do that, it won't matter how benign the terrain is. It wouldn't do us much good to cover 200m/sol for a few weeks, only to kill that wheel.

I should add that just now our progress is further constrained by the lower energy levels we're experiencing as a result of Martian winter's onset, but that will relax after solstice.

So, for now, you should figure that the flat terrain will still have a 70m/sol speed limit. We'd like to raise that limit just as much as you would, though, and we certainly will if we can!