2009-09-06

Spirit Sol 241

If all goes well, I don't have a job. For the next ten days or so, that is -- we won't be driving the rover or moving the IDD during conjunction, so I can spend the time on other projects.

If all goes well. Which, again, we won't know until toward the end of the SOWG. But the plan is that there won't be anything for me to do -- and, indeed, the confirming NAVCAMs of the last IDD placement arrive on schedule, and the IDD is right where it's supposed to be. I flip back and forth through the images, and everything just looks like it went perfectly.

Luckily, there are sharper eyes than mine looking at these images. Rich Petras spots a dark clump on the MB, one that's not supposed to be there. When we look more closely at the images, we discover that the MB picked up some dirt when we used it to touch the soil. (The MIs also clearly show this dirt missing from the soil patch itself.) From that point on, each image that shows the MB shows the chunk of dirt riding along with it, hanging off the outside of the contact ring.

Including -- uh-oh. Including the image we took just before placing the MB on the filter magnet. Which means we just put a whole bunch of dirt onto the magnet.

It's unlikely this will be a major problem. Probably, the worst case would be that when we placed the MB on the magnet, the closing contact ring squished the dirt into the MB's own field of view. If indeed this happened, they'll likely be able to recalibrate the MB to subtract out the dirt's effect. And maybe we'll find a way to shake it off, or scrape it off, if it doesn't look like it'll fall off by itself.

I ask the scientists whether they want us to do anything about this nextersol -- maybe we could retract the MB, image it to see if the soil's still there, check out the magnets, whatever. But they decide against it. I've put the arm where they want it to be right now, and they don't want to risk that. They'll want to inspect the MB and the filter magnet more thoroughly, but they want to wait until after conjunction to do it.

So that means no IDD work nextersol -- nor, indeed, through conjunction -- and therefore nothing for me to do.

Well, I guess there is one thing to do -- we need to start laying out a long-term post-conjunction drive plan. The next science goal is to reach Pergamon Ridge, about 75m east from Conjunction Junction. It's pretty easy to plan this path; there's no good way to get there from here, but Ray and Bethany and I look at the insolation maps and decide we'll head to the northeast. As we go, we'll keep taking pictures of Pergamon Ridge. If a path opens up, we'll take it; otherwise, we'll have to treat Pergamon Ridge as unreachable.

And that's it. I wish everyone a Happy Conjunction, and go home.

[Next post: sol 258, September 23. Sorry about the long delay; that's what happens when a gigantic ongoing multi-billion-year-old nuclear explosion floats between you and something you want to send radio signals to.

Most of us spent these two weeks catching up on other work, or taking vacations. I did some of the former, but used about half the time to write an ops tool that had been sitting in my head for months.

I called it "mPhoto," and it was conceived as a sort of "iPhoto for MER." The idea was to quickly render a simple grid showing thumbnails of all of the recent images, enabling the user to rapidly zero in on images of interest. In addition, it provided some very simple image-manipulation facilities, and the ability to save the images in more useful formats than the one the project normally uses internally. Partly, I wanted the tool itself, and partly I wanted a chance to experiment with writing software in a different -- frankly, a somewhat sloppier -- way than I normally do.

It didn't come out perfect, but I was very happy with it, given that I explicitly gave myself a time limit of one week to develop the entire thing. Despite its limitations and lack of polish, it still does some things better than any other image-browsing tool on the project, so that even now it's still used by me and others. It scratched my itch, and I had fun making it.]






Courtesy NASA/JPL-Caltech. One of the NAVCAM images showing the chunk of dirt that stuck to the MB, shortly before the sequence would put the MB on the rover's magnets. You can see the chunk of dirt on the MB contact ring, near the top of the image.





Courtesy NASA/JPL-Caltech. Sure enough, the MI images -- like this one -- show a chunk of dirt got torn out of the soil where the MB contacted it.

1 comment:

Unknown said...

I've been reading this since shortly after you started posting it. It's one of the first blogs I read when I check my subscriptions in the morning. But because I read it on Bloglines, I probably don't count as a daily hit. So here's my word of encouragement.

I'll be loooking forward to the next installment.