Spirit's On The Move

That showed us where Backstay was and what it looked like. Next we used Mini-TES to check out a lot of the interesting-looking rocks in the Pancam scene, to get a handle on what they might be made of.

That gave us a hint that Backstay might be something new, and made us decide to go after it. Then we used the rover's mobility system to drive over to Backstay and put it within reach of the arm. After that we used the RAT to clean off the rock's surface, followed by MI, APXS and Moessbauer on it to see what it was really like.

And the answer, to everyone's delight (particularly the Mini-TES guys, who had been the advocates for going to Backstay in the first place) was that it is indeed a martian rock type that we'd never seen before.

It's a basalt, as you might guess just from looking at the pictures, but one with more titanium, more aluminum, less iron and more potassium in it than the basalts we saw out on the plains.

We can't tell where it came from, of course, since it's probably a piece of impact ejecta, and maybe one that's pretty far from home. But it's definitely something new and interesting for the geochemists to puzzle over.

And with that, we're off into unknown territory once more. It really does feel good to be on the road again. (In fact, somebody put up a picture of Willie Nelson at today's Spirit SOWG meeting just for that reason!)

The current plan is pretty much just drive-drive-drive for awhile unless something interesting and unexpected pops up in the images. So look for nice new vistas to the south as we work our way around the hill.

Good progress too at Meridiani, though we're being slowed down a bit right now by being in the period we call "restricted sols".

This is what happens when Earth time and Mars time line up inconveniently, so that we have to plan each sol on the basis of what happened on Mars not yestersol, but the sol before. Despite being in restricted sols, we've gotten Opportunity through most of the three-point turn we're using to get her facing back toward Purgatory Dune.

The next step will be to get into a safe position on the dune to try some arm work on it before we move on.

And dust is down a little at both sites, and Mini-TES on Opportunty seems happy and healthy. So life is good.