Victoria Crater

While Spirit is stuck in one place for a while, looking at the sky and dirt, I've been paying a lot more attention to Opportunity. Over at Meridiani Planum, we're headed toward this huge (by rover standards) hole in the ground, Victoria crater. Craters over here are named after great ships of exploration, and Victoria was the only ship to successfully return from Magellan's voyage around the world. Victoria crater is just about the size of Meteor Crater here in the southwest, a little less than 1 km wide. Check out the rim of Victoria crater as Opportunity approaches.

Victoria punched a deeper hole into the Meridiani Planum surface than the last big crater Opportunity visited, Endurance crater. Endurance crater was where we got to check out Burns Cliff, a fantastically well-preserved set of sedimentary layers in the inside crater wall that showed crossbedding, evaporite mineral casts, and the little hematite blueberries. Craters are nature's roadcuts, the way these little mechanical geologists will be able to check out what's underneath the surface of the plains, and we're all hoping that the inside walls of Victoria show us more wonders.

Right now, Opportunity is about to roll up onto Victoria's ejecta blanket, which is the apron of material that was thrown out of the crater and rained down around it. When craters form, a lot of stuff gets thrown out from a depth roughly as much as the drater diameter. As the rocks deform and fail with the crater shock, the final crater is much shallower, only about a tenth as deep as the diameter. So, the rocks in the ejecta blanket come from much deeper down than the rocks at the bottom of the crater now. If you want to look for the deepest rocks, you look at the edges of the ejecta, which is what's next on our journey. We're stopping nearly every weekend to check out our surroundings to see if anything is different yet.

It's a little ironic - we're now interested in changes in the rocks but all we see are really large expanses of the same Meridiani Planum bedrock. One of the science team members remarked that last year, huge expanses of crossbedded bedrock would have been nirvana for this rover. But the scientists were so good at eking out the geologic history from what small outcrops they had that now we are just enjoying this area for the ease of driving over lots of flat material.

Martian winter work, terrestrial summer work

Spirit is nestled snugly in her Winter Haven and we are all getting in on the chance to conduct experiments that we never seem to have time for when we are on the move. Spirit is parked on the slope of Low Ridge, an arcuate feature that might be connected to, and possibly related to, Home Plate. Directly in front of the rover is an expanse of drifted dust and/or soil, which is the first target of an intense campaign with all the arm instruments to make measurements progressively deeper into the soil. There's also a long list of rock and soil targets for miniTES, some long-timeline atmospheric observations, and a monster panorama of our surroundings in all 13 Pancam filters, which should be really beautiful. For those of us interested in rocks, we have poor choices right now. There are a couple of clasts and possibly a shingle in our workvolume, which we will investigate. Several of us are hoping that after the solstice, we will be able to move to some rock targets ahead of us to figure out the geology of Low Ridge, its relationship to Home Plate, and the origin of some of these volcanic units around us.

In terrestrial analog news, I will be heading to the Ries Crater in Nordlingen, Germany, after the Meteoritical Society meeting this summer. Ries is a well-preserved 24-km diameter, 15 Ma crater with post-impact lacustrine layers inside and fantastic outcrops of ejecta. The Ries ejecta may be a good analog to Martian double-layered ejecta deposits. There is an upper ejecta layer (suevite) which is a mix of deep material and impact melt, overlying a lower layer (the Bunte breccia) which is an interesting unit formed when the first (shallow) ejecta was ballistically emplaced and churned up the substrate, mobilizing it and causing a radial flow. It is rumored there are distal parts of the Bunte breccia containing crossbeds and lapilli that may be potentially interesting to compare with proposed origins of Meridiani and/or layers in the Inner Basin. Cool!

Roving Mars!

Rob and I finally went to see Roving Mars this weekend in Phoenix. It's an IMAX film about the launch and landing of Spirit and Opportunity and has some really spectacular full-screen renderings of some of the early data. It wasn't as long as I would have liked but it was amazing to see some of the pictures on the humongous screen. Also, I was glad to see some of the cenes of the scientists when landing occurred - I was in a tent in Antarctica at the time and missed the excitement. Something about Steve Squyres having his own IMDb entry strikes me as hilarious, though his brother Tim is a bona fide Hollywood editor.

Spirit is definitely nestling down for a long winter in her present location. Unfortunately for me, there's no good rocks right in front of the rover, so my grand plans for multi-rock analysis campaigns will have to wait until after the southern Martan winter solstice (August 8). The soil and remote sensing people are kicking into high gear for the first part of winter and have some really cool plans for looking at different levels in the soil and acquiring the McMurdo Pan, a grand 13-filter panorama of everything around us. Opportunity is still zipping along, less than 1500 m to go to Victoria crater!

So, while I am supporting operations, I'm trying to dig into some data analysis, including multivariate analysis. I took linear algebra in college as an elective because I am such a geek. It was one of the few classes where I succumbed to the whining refrain, "When will I ever use this in the real world?" Well, 15 years later, it's come round to haunt me with whispers of eigenvectors.....

Sand trap

Wow, I'm sorry I haven't updated you all in a month! I've been traveling a lot this semester for work unrelated to MER.

Here on Earth, we had a fantastic turnout for the MER sessions at the Lunar and Planetary Science Conference, where the team updated everyone on the current science and other members of the community got to offer their own interpretations. Always lively, sometimes contentious, never boring. It's an exciting time to be looking at this data! I presented my poster on my ejecta calculations - how much ejecta from far-away terrains should we expect to find at the MER landing sites? I'll give you a clue: not much. But you can see the whole paper here. It's my first single-author paper and it was published on my birthday this year!

Up on Mars, Spirit is dragging a wheel. It's the right front wheel, the one that went gimpy early in the mission. At this point, it is steerable but not driveable and so it's just dragging behind us. In principle, that's fine and the rover is totally ok driving with 5 wheels. In practice, we got terribly bogged down in some soft, sandy soils and had some real scary days where the rover wheels dug in and we watched our power sink lower and lower. We re-evaluated our plans to get to north-facing slopes and decided to retreat back the way we came to better ground.

We chose a Winter Haven along Low Ridge, a small feature possibly connected to Home Plate, with nice slopes and lots of rocks. We're now developing plans for what to do there as Spirit waits out the winter. I think it's going to be a really exciting time because we will finally have time to sit in one place and do some detailed analyses of rocks and soils, so I'm actually very much looking forward to the winter, despite the scary power numbers!

On the other side of the planet, things are looking zippy - literally. Being nearer the equator and dust-free, Opportunity continues to have a favorable power situation even into the wintertime and is making amazing mileage along dune troughs and outcrop rock. We're only 2 crater radii away now from this humongous crater, Victoria, which is Opportunity's destination. It's old and eroded but probably dug pretty deeply into Meridiani Planum, so it should be super interesting when we arrive.

Rewarding rock

Wow! My commands to Spirit to use her APXS and Moessbauer instruments on the rock last week apparently were the right ones and got through with no problems (sigh of relief here) and good thing too, because the rock is awesome! Obviously I can't post many details here, but I think I can say that it's probably some combination of a volcanic rock and Martian weathering, like many rocks we've seen, but in a weird and new and very interesting way. You might hear about it at LPSC next week.

LPSC is our big planetary science conference, held annually near the Johnson Space Center in Houston. It started as the Lunar Science Conference back in the day, then expanded to become the Lunar and Planetary Science Conference. For the last couple of years it might as well have been the Martian and Other Planetary Science Conference. There's at least one Mars session every slot, and sometimes Mars goes head-to-head with itself. I'm looking forward to seeing what everyone has been up to!

Another press release

I was excited to write the press release for our first images of Home Plate a couple of weeks ago, check it out here.

Investigating Home Plate

Spirit has spent the last couple of weeks on her Home Plate campaign. Since we arrived, we've seen layering in the rocks and some chmical evidence that might point to Home Plate being volcanic in origin, which is really interesting. No rover or lander has been to a volcanic center on Mars before! So we're taking the time here to get as many in situ analyses as we can plus a whole host of Pancam images and miniTES work. This week, I served as APXS/Moessbauer uplink lead, which meant that I determined what the rover needed to run the APXS and MB instruments on Spirit at the times we wanted it to. Now that the rovers have been going so long, some of this is old hat and doesn't need to be reinvented every time we do an analysis, but there still needs to be someone to make sure everything is ok for the instruments!

For the first time since I joined the team, I've been way too busy for the last three weeks with other aspects of my job to really keep up on what one rover is doing, much less both of them. It's much more clear to me now why they need new, enthusiastic people to come in and put the time into the rovers. I was glad to have a specific job to do this week that forces me to look at the data coming in and participate in the process. It's easy to get overwhelmed after missing even a couple of days!

Home Plate

We’ve finally made it through part one of our race against winter, to the feature called “Home Plate” in the inner basin. Wild theories of its origin abound - everyone is getting in on the speculative volcanology. We’re now parked perilously up against an outcrop on the outer ring of Home Plate and doing a very nice campaign bringing all our instruments to bear. Keep an eye on the JPL home page for details of what we find!

Yet more training

This week I spent a couple of days at the Johnson Space Center in Houston learning the ins and outs of two of our arm instruments – the Alpha Proton X-ray Spectrometer (APXS) and the Moessbauer spectrometer (MB). These two instruments give us detailed, quantitative information on the major-element chemistry (APXS) and mineralogy of the iron-bearing phases (MB) in the rocks, and are the two instruments that I’m most interested in for my work. So, as one of my operational roles, I wanted to learn more about how they work and how we make them work.

Both the APXS and the MB were designed and developed by German teams as contributions to the MER mission, and they are led by the Payload Element Lead scientists in other countries. They are the ones who know the real ins and outs of these instruments. But, in the current mode of remote operations, two people at JSC know an awful lot about the day-to-day operation of the instruments, and Houston is a lot easier to get to than Germany.

These three days were really rewarding for me. Days like that are the ones that keep me going through the slump months. It was the busiest couple of days on both rovers that we could have asked for, as both were using their arm instruments on interesting outcrops. I got to see lots of friends and meet new colleagues, learn something really interesting that only a few people in the world can do, feel confident that I can do it well, and talk about the science with a collegial bunch of planetary scientists. As an extra bonus, while there, I also got to see the Stardust samples making tracks through their aerogel collectors, just a few weeks after their return from Comet Wild/2.

The Earth's a planet too

When I first joined the Athena team, I went out to dinner with my fellow New Mexican, Larry Crumpler. He said something that stuck with me - that the value of planetary geology is what you gain in being able to see the Earth differently, and hopefully, better. I'm finding myself looking around me all the time and asking, "How would the rovers see this?" It's especially true now that we're rounding third and heading for "Home Plate," a mysterious feature that could be a crater, a salt pan, a lava flow, or come combination of all three.

On my commute home every evening, I head up La Bajada hill, an abrupt fault face capped with spectacular columnarly jointed basalts of the Caja del Rio field, where I live. It's usually getting on dark when I creep up the hill, but this week I happened home early and saw my passage through the tumbling basalt boulders, steep arroyos, and deep red soils. I really paid attention to the illumination, the relationships between boulders and layers, to what I saw and what my brain filled in as "normal." It was one of those great moments when I'm so happy with my own brain. Then, later in the evening, it got dark and there was Mars itself, a shining orange point.

Downright Frothy!

I wrote my first press relase for the rocks I fought for last week and now you can see it on the JPL web page. Here's the text:

Gusev Rocks Solidified from Lava

In recent weeks, as NASA's Mars Exploration Rover Spirit has driven through the basin south of "Husband Hill," it has been traversing mainly sand and dune deposits. This week, though, Spirit has been maneuvering along the edge of an arc-shaped feature called "Lorre Ridge" and has encountered some spectacular examples of basaltic rocks with striking textures. This panoramic camera (Pancam) image shows a group of boulders informally named "FuYi." These basaltic rocks were formed by volcanic processes and may be a primary constituent of Lorre Ridge and other interesting landforms in the basin.

Spirit first encountered basalts at its landing site two years ago, on a vast plain covered with solidified lava that appeared to have flowed across Gusev Crater. Later, basaltic rocks became rare as Spirit climbed Husband Hill. The basaltic rocks that Spirit is now seeing are interesting because they exhibit many small holes or vesicles, similar to some kinds of volcanic rocks on Earth. Vesicular rocks form when gas bubbles are trapped in lava flows and the rock solidifies around the bubbles. When the gas escapes, it leaves holes in the rock. The quantity of gas bubbles in rocks on Husband Hill varies considerably; some rocks have none and some, such as several here at FuYi, are downright frothy.

The change in textures and the location of the basalts may be signs that Spirit is driving along the edge of a lava flow. This lava may be the same as the basalt blanketing the plains of Spirit's landing site, or it may be different. The large size and frothy nature of the boulders around Lorre Ridge might indicate that eruptions once took place at the edge of the lava flow, where the lava interacted with the rocks of the basin floor. Scientists hope to learn more as Spirit continues to investigate these rocks.

As Earth approaches the Chinese New Year (The Year of the Dog), the Athena science team decided to use nicknames representing Chinese culture and geography to identify rocks and features investigated by Spirit during the Chinese New Year celebration period. In ancient Chinese myth, FuYi was the first great emperor and lived in the east. He explained the theory of "Yin" and "Yang" to his people, invented the net to catch fish, was the first to use fire to cook food, and invented a musical instrument known as the "Se" to accompany his peoples' songs and dances. Other rocks and features are being informally named for Chinese gods, warriors, inventors, and scientists, as well as rivers, lakes, and mountains.

Speculative Volcanology

I've been mostly interested in what Spirit is doing in Gusev crater, because I am a hard-rock kinda girl, and that's where the good rocks are. But this week, I documented for Opportunity, and had a great time! Opportunity is sitting at a location called the Olympia outcrop, that features some really exceptional ripples and crossbedding, and the team is taking its time getting the coverage this outcrop deserves. While I was on, we planned several mosiacs using the Microscopic Imager (MI). The field of view of this little camera is about 4 pennies if you arranged then 2 by 2. So to get a lot of coverage, we take a bunch of images and mosic them together. In addition, because the instrument is so close and the surface is not exactly a plane, we take a stack of images moving a few millimeters closer to the surface each time, and then examine them to find the one that is in the best focus. It's not really difficult to get these MI mosiacs, but there are a lot of detailed commands and it is challenging to make sure they're all correct and in the right order. But of course, the engineering team is terrific at doing this by now!

On the Spirit side, I've been dabbling in speculative volcanology, a new discipline I could really get into. Basically, we're seeing lots of volcanic rocks and the orbital maps seem to show lava flows as well. But, we haven't gotten any decisive data yet, and I'm not a volcanologist. It has been fun (for me, anyway) to learn about various modes of volcanism from my officemate and from other members of the team who are willing to listen to my latest crazy idea!

Pattern recognition

I'm doing Documentarian for both Spirit and Opportunity this week. It's been described as "watching paint dry," but I actually find it interesting to know in exquisite detail what the plan is today. But there are long stretches where I have to be half-listening to a roomful of people and wait until there's something important being talked about, so I can't go off and work on something that really absorbs my brain. Instead, I have to rely on my brain's pattern-recognition to alert me. When you’re next in that situation, and want to keep your pattern-recognition skills up to par, try the online version of my favorite game, SET.

Science Team Meeting

I spent last week at JPL in Pasadena for some training and my first Athena team meeting. It was a long but fulfilling week for me!

The first two days, I shadowed the Keeper of the Plan, a job I hope to start in a month or two. This job is to keep track of all the science activities people request for the day. Like Doc, which I’m doing right now (right now!), it’s a good way to keep my interest in the day-to-day activities of the rovers. It’s like the difference between taking a class for credit or audit – when I audit a class, it’s more difficult for me to find the time to devote to it than if there’s something riding on it. During the first part of the week, I spent the mornings in the science meetings and the afternoons with the planners and learned more about the process. Steve Squyres himself was there as chair, so it was wonderful to sit through the process with him and pick up bits of knowledge.

While we were all at JPL, we had some very crowded planning meetings and happened across a white sand patch that turned out to be packed with sulfur. My roommate Aileen and I were up very early in the mornings to get in and help with picking targets! I know things are busy when they cut into my precious sleep time.

The last three days were spent with the entire Athena team, gathered in the auditorium to talk science. I was very intimidated at first, had to introduce myself to everyone and felt like I should justify my addition to the team. But everyone was super, very welcoming and interested. I gave a talk on my interests that went ok - I wanted it to be fabulous, but it was just ok. I couldn’t think of anything funny to put in it so just gave it straight. One thing I resolved on the second day was to speak up when I had a question or comment instead of asking my neighbor quietly. Surprisingly to me, I did that 5 times! Ultimately, the talks and the time to meet with people were great for me to see what we are still struggling with, what new ideas can be generated, and what I have the tools to jump into.

Gathering courage

I had a great week as a science theme group lead for Spirit. This week we had little to do as we drove the rover hard, even dipping into the battery power, to push it along the road toward its winter haven. In cases like this, it’s up to the scientists to make sure we don’t zip along without at least looking around once in a while. Because we’re now traversing the basin floor, a lot of us want to know what the basin floor is made of. We passed a bedrock outcrop midweek but couldn’t stop. So I screwed up enough courage to make the case in our Friday meeting to look for a bedrock outcrop as we move toward our destination. I know a lot of people are thinking the same thing, so it wasn’t a complete shot in the dark, but I still felt like I was sticking my neck out. Fortunately I didn’t seem to embarrass myself and I think people took me seriously, though there probably isn't enough time to alter our path in the way I suggested.

Rock Star

I was asked for my autograph recently, by a collector who has an old USGS Viking map and is getting it signed by prominent Mars scientists. When asked, I had to demur – I’m certainly not in the league of Bruce Murray, Steve Squyres, and Ray Bradbury! But this great guy thought that maybe someday, I would be :) I got to choose my favorite spot on Mars, and I chose Argyre Basin. Argyre is one of the best-preserved large impact basins on Mars. It’s more than 1000 km across, stratigraphically old, and has a beautiful mountain ring around it that is presumably the remnants of its ejecta. Most of the work I’ve done in my career is related to trying to reveal the history of bombardment in our solar system in its early years, and when my attention turns to Mars, that’s what I wonder about. We don’t have any plans at present to visit Argyre, but it’ll be a fantastic location someday to learn about Martian cratering history, large basin formation, and other things like the past Martian geotherm and possibly the climate record in the infilling sediments.

(With apologies to Sir Mix-a-Lot and to you, dear reader)

I like Big Basins and I cannot lie
You scientists can’t deny
That when a crater formed 4 billion years ago
And that’s where the spacecraft goes
You’ll get sprung! Wanna land your stuff
Cause you’ll notice that basin’s stuffed
With climate records in the sediments
And ejecta in the pediments
Ooh ring of mountains
Of knowledge it’s a fountain
Push that record later, later
Cause this ain’t no average crater

Science Themes

I didn't get to upload a couple of entries last week - they're now posted below by date.

This week I have my first shift as a science theme group lead. The operations of this mission were carefully structured by Steve and his management along science lines where the team thinks of the rovers as integrated instrument packages. That may sound mundane, but in the world of missions, frequently instrument teams find themselves pitted against each other for time and power resources. The science-based approach has worked well on this mission and encourages us all to work together toward our common goals of exploration and discovery.

The science groups are centered around geology, mineralogy & geochemistry, atmospheres, and physical properties. Scientists from each group are responsible for ensuring that activities get planned that support these areas of Martian science. My interests are mainly in geochemistry and mineralogy, so I am in that science group, and this week I am the lead advocate for the group. In practice, this isn't a lot more time than I'd normally put into looking through the data and taking an interest in what's coming up, but there are a couple of systematic observations I'm responsible for suggesting, and of course, I'm a little nervous about not making a fool of myself :)

1/1/05: Leap Second

This year’s leap second may not help me and my habitual 10-minutes-late-for-everything, but it did get radiated to all the spacecraft. Just in case you were worried.

12/31/05: Enforced Vacation Break

Happy New Year! I’m here at a Santa Fe Starbuck’s with my laptop and a Tmobile hotspot, checking out what the rovers accomplished over the long weekend. Did I mention that I’m completely addicted? :)

Most of the MER scientists and engineers got a well-deserved break over the holidays. But the rovers wouldn’t know what to do with a day off. They get so much new energy every morning, like my cat! So a few people were busy right before both holiday weekends putting together multiple 3-day plans to keep the rovers busy while we went home to families and celebrations. The University where I work is closed all week between the holidays, and it’s a pleasant break to not have to drive the hour+ to get there, so I was happy to bring my speakerphone and laptop home for the week and keep up remotely.

I get to the Starbucks closest to our house (it’s about a 15-minute drive into town) for an hour in the morning while Rob’s still asleep and just download what’s available – images, documents, everything. Then I bring it home and sort through it, make mosaics and false-color views, read what actually got accomplished in the last plan, see if I can spot interesting targets where we are, make sure I understand where we’re going and what people think we should do. Then, I call the telecon line from home and participate in the science planning process for the day. It’s total about 3.5 hours for the day if I want to really get into it. There are summaries and other ways to stay abreast of developments on a weekly basis, like this great web site at JPL that I use to check on Opportunity while I am focused on Spirit.

But for the rest of the week, I did take vacation. Rob also had the entire week off and my brother came into town for Christmas and the first part of the week. He’s super fun and we had a fabulous 5 days. Rob and I had big plans to be tourists in our own state for the rest of the week, but those all got canceled when we both got sick and spent the next 5 days cooped up at home sleeping, reading (me), and playing computer games (Rob). Objectively, that’s probably the vacation we needed.

12/28/05: The Lost City of El Dorado

Since I've been involved in this project, we’ve been steering Spirit down the southern flank of Husband Hill and into a basin. Up against the leeward side of many of the hills in this area are vast (from the rovers’ perspective) black dunefields. They’re black because they’re not covered with the ubiquitous red Martian dust, which means they must be relatively young or frequently moving. They’re also probably black because they’re basaltic.

We had a team meeting to decide whether we wanted to spend a couple of weeks heading for one of these dunefields near us, called El Dorado. There are several members of the team interested in aeolian processes (how sand moves) and physical properties of the martian surface (which might be very different in fresh dunes vs old soil), who are eager to go. But what convinced me to get on board was the fact that El Dorado is visible from several orbiting spacecraft. It’s an exceptional opportunity to collect real Martian ground-truth to help interpret orbital data, a topic about which I’ve been known to kvetch.

So down through the rocky, desolate Indian country Spirit went, trading among the Apaches and Comanches, heading southwest on the path to El Dorado. The rover planners outdid themselves again, with some lengthy beauties of drives topped off with a scuff right on a dune face. And here we'll spend a long holiday weekend with the arm out, using all our instruments in chorus on the black sands of El Dorado.