2009-03-11

Spirit Sol 67

The downlink assessment meeting has its share of happy news. They got a cool animation of Phobos transiting the sun. It's a crude animation -- only two or three frames -- but it's something that's never been seen before. That is, it's the first time we've seen Phobos transit the sun; the first transit by Deimos was snapped by Opportunity a sol or two ago. Phobos is larger and closer to Mars, so it obscures more of the sun; Deimos is just a tiny speck, but Phobos took a good bite out of that sucker.

Mark Adler reports that the sequence timings were a little messed up, so the traverse didn't complete. We're still a couple of meters short of the edge. But it turns out that this might be fortuitous: at this point, we lose elevation as we get closer to the rim, so we're getting a better view from where we ended up. Still, because of the way the drive ended, we don't have images of the terrain immediately under the rover. Thus we can't be sure it's safe to deploy the IDD; this limits what we can do tomorrow.

Our view of the crater itself has never been better. "In a sense, we've just found a new universe," Golombek says as a way of kicking off the "what's next" discussion. It falls to Dave Des Marais to re-frame the question in the terms I suspect are on everyone's mind: "What're we gonna do for LPSC?" (The Lunar and Planetary Science Conference is the conference they've been building up to; it occurs next week.) We'll probably just scoot forward 2m or so and take a legacy panorama. This will likely be at least 180 degrees or so, in color, and should look absolutely spectacular. And when will they need to have this done? "What day are the talks?"

I have a lot of work to do, but most of it I can do at home. I came in mainly to do a favor for Bob Deen, who (like me) is writing a paper for the Space Ops conference. (I wrote mine last night, after realizing the deadline was 10 days earlier than I thought. Most people, it turns out, are even later than I am: Frank, Jeng, and Brian, at least, haven't done theirs yet.) He needs some screen shots of Spirit exploring the trench, since he's particularly proud of the trench mesh and is going to discuss it in the paper. I put the screen shots together for him quickly, and he more than repays the favor by showing me a beautifully clear 3-D view of the crater, looking over the rim into the enormous bowl.

I spend some time catching up on my email, the backlog of which has grown to scandalous proportions. Andy sees me and asks the usual question: "So are there any days you don't come in?" I explain that I originally came in on my off days to catch up on the pictures, but I don't have much time for that any more; now I use my off days to catch up on all the work that piles up when I'm on shift. He tells me his strategy for dealing with it: "I just let things fall behind."

My email contains one more piece of good news: the free ice cream is back! Through the end of the nominal mission, anyway, which means until April-ish. Someone will have to go out each week and buy about $1000 worth of ice cream with his own money, then get reimbursed by the project. Mike Adler has already done it for this week. I seriously want to do this just once, for one simple reason: I want to see the look on the cashier's face when I show up at the checkout line with $1000 worth of ice cream.

The only thing funnier would be to throw in one box of tampons.





Courtesy NASA/JPL-Caltech. Phobos transits the sun.


3 comments:

Yarp said...

Do you know how long does the actual Phobos occultation last ? This is a common question I have with GIF animation. There are some clouds of dust storm animations around (at least one from Spirit) but we don't know about the real length.
This is a great blog. Thanks.

btw Great to have the ice cream back. Not the lesser good reason to work for MER.

Doug Ellison said...

There was a science paper pulled out of the phobos and deimos transits... http://marswatch.astro.cornell.edu/mer/Bell_nature03437.pdf

Deimos, being further away and thus slow - they're about a minute and a half. Phobos, being closer and faster, they're about half a minute at most - often quicker if it just takes a bite out, instead of transmitting across the middle.

I did some animations of what they might look like in real time that JB put on the pancam website -look for the quicktime movies - http://pancam.astro.cornell.edu/pancam_instrument/projects_4.html

Yarp said...

Thanks Doug, the Movies are just great. Exactly what I wanted to see.
And the Pancam website is very very interesting and so colorfull.