Wednesday, September 27, 2006

Martian craters



I know you've all been waiting for it as eagerly as we have .... today we're planning our last, cautious bump to the rim of Victoria Crater! Check out the images of Opportunity's approach via her navigation cameras: Tuesday and Wednesday. Today we'll be planning out the campaign that we'll conduct at Victoria. Basically, Opportunity will start with some spectacular remote sensing, so look for that later this week. Then, the team will decide which direction to start circumnavigating Victoria. We're expecting some fantastic orbital imaging from the HiRISE camera onboard the Mars Reconnaissance Orbiter that will help guide the team's decisions on where to stop and hopefully, where to think about entering this beautiful crater! Stay tuned....

Terrestrial craters

Last weekend I took a group of students and other scientists from UNM to Meteor Crater, just down the road from us in Winslow, AZ. We circumnavigated the crater (~2.5 km) in the morning and spent the aafternoon looking at ejecta nearby. It was good to see again just what a crater form looks like in person. When you see pictures, craters tend to look like bowls with gently sloping sides, and it's easy to think of the rovers as skating down them like halfpipes. But when you really see them in person, impact craters are imposing features, lined with near-vertical cliffs and jagged outcrops.

It was a real treat to have a fellow MER scientist, proto-Dr. Shawn Wright from ASU (below, with me at the crater edge), join us there to show us some of the remote sensing he did of the crater. Shawn came fresh off field work looking at potential craters in South America and though tired, he was enthusiastic about guiding us to his favortite locations around the crater. At several stops, we could easily trace cliff outcrops and correlate specific ejecta lobes with remote sensing imagery because of Meteor Crater's unique (and fortuitous) target material: discrete layers of red siltstone, yellow limestone, and sugary white sandtone.

Wednesday, September 13, 2006

It's dark when I wake up

I know we're sliding into autumn for real when the sun's no longer up when my alarm clock goes off at 5:30 am (!). My daily attitude is definitely controlled by the sun - on sunny days I'm bouncy and energetic, and rainy days make me want to curl up on the sofa with a good novel and a warm cat. As the amount of sunlight in my day shrinks, I feel like I lose energy - just like our little friends on Mars. So we're all very relieved and happy that Spirit made it through the depths of another Martian winter with even enough energy to continue doing at least a little bit of science nearly every day. Power levels are on the rise again, little by little, and the rover appears to be in good health. Of course, the rover doesn't have to wake up until local sunrise *yawn* .

Opportunity, being near the equator, has my perfect life - sunny and warm year-round. She continues to zip along toward Victoria Crater, whose ejecta blanket turned out to look a lot like the normal Meridiani plains - flat, hard, some sand drifts. On sol 929 Opportunity almost got a hole-in-one by driving 100.31 meters to the small crater Emma Dean, where we are trying to look at what the bedrock in the ejecta blanket is. We got our last good look at the "normal" Meridiani rock at Beagle Crater (yes, another shameless plug for a caption I wrote). It's a really spectacular mosaic - and - there's a super-cool quicktime window you can open and scroll around the panorama from the center. Sweet!

August travel update II

I mentioned a while back on this blog that one of the highlights of my summer was going to be visiting the Ries Crater in southern Germany - and it was. Here's a photo of me with Walter Goetz, who's one of the investigators on the MER Magnetic Properties Experiment. Walter joined me, Rob, and Gisela Poesges from the Ries Crater Museum for 2 days of fun on the outcrops inside and outside the Ries. We were also joined on the second day by Iris Fleischer and a group of grad students from the Mossbauer group in Mainz. It was super fantastic, really amazing to see the different kinds of ejecta so well preserved, we had tolerable weather except for one downpour, and Gisela knew all the best places to see shatter cones, the crater rim, megablocks, and lunch stops! Walter and I both got a lot out of the trip, trying to see impact products from the rover's point of view, and bringing back lots of samples for further study. Rob maybe didn't get so much out of the rocks, but Gisela did give him a chocolate model of the Ries Crater.



After Ries, Rob & I spent a couple of days in Krakow and western Poland checking out my family roots, then drove to Prague for the IAU meeting. It was a timely meeting to attend because it was where all the planet-definition discussion was heating up, culminating in the vote that redefined Pluto. I couldn't vote, because I'm not a member of the IAU, so don't send me hate email. Honestly, I didn't think it would fly, because at a contentious lunchtime forum during the week, the panel asked for an informal show of hands and the proposals were soundly rejected. Basically, everyone is upset at different aspects of the proposal so there was no consensus. It's far from over and don't be surprised when the IAU takes this up again in 3 years at their next meeting.

(You're wondering how I would have voted? We now understand that Pluto is the prototype of this belt of icy objects in the outer solar system - it's a new discovery and reflects our new understanding of the solar system, and *that's* exciting. How to codify it scientifically seems less of a problem than dealing with the "public outrage." I did a radio interview last week on the topic and one of the other guests says he knows someone who learned the planets *before* there was Pluto. I wonder what that was like, did people protest that now all the textbooks were obsolete and how could they be expected to come up with a new mnemonic? Crazy.)

August travel update I

I had a great time traveling in August but I am so happy to be back in the saddle. I had real withdrawal symptoms while I was off doing other things and not always able to keep up with what's going on on Mars. I carried my laptop around, hungrily looking for wireless connections and internet cafes :)

In Zurich, at the Meteoritical Society meeting, I had a great time talking with some of our European APXS/MB colleagues including Christian Schroeder and Jutta Zipfel. We're all very excited that both rovers just uplinked a flight software update -an amazing thing to do so late in the mission - that includes some fantastic new capabilities for our little buddies. The most exciting thing for us IDD types is the ability to go-and-touch. Up til now, we need a full sol to approach a rock and downlink images from the hazard-avoidance cameras, then there's a human in the loop to assess the images and determine how safe it is to deploy and extend the arm out to touch a rock that we want to look at, then then next sol we uplink the touch command and can start taking data. Because of the vagaries of the planning process, this can actually take more than one sol sometimes. The new software will (hopefully) allow the rover to make an independent determination of a safe place to put the arm instruments and go and do it without us, saving us a sol (or more) of real time.

Also in Zurich, I found out to my surprise and infinite delight that the asteroid formerly known as 1981 EB28 is now officially 6816 Barbcohen! How cool is that! Read the UNM story about it here. It's only a tiny speck of a rock in the main belt, but this is where it was on Aug. 10, the day I found out!



You can see where it is any time by going here. Of course, Spirit and Opportunity already have theirs too!