The Tuesday morning press briefing is about to begin. I'll post notes as soon as it's completed. I may be cut a bit short today because it's BugDay, our weekly "getting involved with Mozilla" event.
(notes are really rough because my connection was pretty bad and I don't have time to clean up because of BugDay)
Chris Lewicki(sp?):
Cutting the umbilical. Severed the 135th and 136th pyro devices to free the rover from the lander. The next step was the first drive of the rover. A small one, but it tested out all of the actuators and mobility system and everything checked out. Then we did our last move which was a 45deg turn in place. We also downlinked 100% of our mission success panorama from Pancam and 100% of our mini-TES octants. (showing some testbed videos and images from the lander before and after these maneuvers) Engineers are extremely happy. Everything is tracking exactly where we want. we're 212deg in yaw.
Joe Guinn: some of the radio techniques to determine the location of the rover. The navigation team was able to guide Spirit to an entry more accurate than anywhere before. Once we were on the surface we used a technique to refine the location to within about 30m (about 100 feet). The accuracy is so good that the biggest uncertainty is in the maps. On the best maps we have available, features can be off by as much as 300-400 meters but given the fact that we've got radiometric solutions accurate to 30 meters, that's our biggest uncertainty. Optical techniques will help us squeeze out the uncertainties. This image shows a progression of the evolution of our understanding of Spirit's location. Large ellipse represents where we planned to land. We were able to take measurements during entry and landing the black ellipse (much smaller) and then there's the little dot inside that black eclipse (closer up image). The red and orange circles represent craters and the white dot represents where spirit is. In order to get an idea if this was really correct we wanted to match it up with an image of where Spirit was going. There was such an image from the DIMES images. Overlay of the Dimes images with the radio solution. In conclusion, we have a really good system for quickly determining the surface location.
Tim Parker: Wow! This is just a hoot :D In this graphic (slide of panorama). We've been pouring over the ground view and with the help of the nav team and the DIMES images. Azimuths to crater rim, then "east hill complex" summit heights and azimuths plotted on Pancam image. Azimuths to south mesas and south southwest hills. This method will disagree some with the radiometric data. This shouldn't be taken as an error in the placement of the rover but rather an error in the Mars control network. The next graphic will show the orbiter view comprised of MOC images mosaiced with two of the DIMES images. here I've plotted all those azimuths as yellow vectors and moved it around until I got a good match with the horizon features and this is what I got.
Steve Squyres: we know where we are now and we also know where we're going. (!!!). With that knowledge we can now intelligently plan a mission-long traverse. To understand why the team has come up with this plan I'm about to show you, it's important to remember why we're here. We will know what lies beneath the material we're on and what lies above it. Go some place where there's a big hole in the ground and then see what lies up higher - find a big hill. Map showing location and objectives. To the NE at a distance about 250 m is a crater 200m in diameter, an extremely attractive target, depth of 10s of meters, a rim 3,4,5 meters high. I don't know what we'll do when we get there but as we get closer we'll enter the ejecta blanket. We'll drive up maybe to the lip of the crater, depends on how trafficable. It will provide a window into the surface of Mars. After we've done that we'll have seen as deep into Mars as we will see in this mission. After that we'll head to those hills. I cannot tell you that we're gonna reach those hills. Vehicle was designed to go 600 meters. These hills are 5 times as far away. We're going to go *toward* those hills. This graphic is what I feel is one of the most evocative images we've taken (view of the eastern hills). This is the direction that we're going to go. As we progress, the detail of the images will get better and better. We will have a better and better chance of finding on the ground materials that originated on the hills. I don't know how close we can get. As we progress we'll investigate materials along the way.
Rob Manning: I can't top those pictures. This is a hoot. 64 pyrotechnic devices have been fired totally flawlessly. Status report of how EDL went: We are going to have better visuals by this time next week. Some facts: interesting development during parachute deployment. Opened perfectly except that the software opened it lower than we expected. Software did exactly right but about a mile lower than our target altitude. Makes things more exciting towards the ground ;-). About 7.5 kilometers height when it opened. speed about 920 mph, 412m/sec. We did have plenty of time. Our descent rate was about 152mph which was quite a bit slower than we had expected. We don't quite know why yet. Either more density or updrafts in atmosphere. The vehicle was actually going 30 mph faster than a skydiver (on earth). Robots have nerves of steel, or copper in this case ;-) We fired rockets at 342 feet, about 100 meters. A little bit lower than we anticipated but software did it perfectly. We ended up cutting the bridle a bit lower. Targeted 12 meters but we had a wind gust near the bottom turned us so we had a significant horizontal velocity when rockets fired. So we had an 8 meter height. Pretty close. Exciting. This wind gust, we did fire our rockets which corrected our attitude and we're very glad we did. Still had a little horizontal velocity left over from our entry angle. Still moving downward a little when the bridle cut. We were surprised but it was not unexpected. Since we had a vertical velocity, we bounced higher than we expected. We had quite a few bounces and we've concluded that we had 28 bounces and we believe we may have bounced uphill. Those scuff marks in sleepy hollow are bounces number 25, 26, 27, 28. Animations next week. Bounces took about 57 seconds. Faster than I would have guessed. Surprised the bouncing ended so quickly.
Q. What sort of changes (for opportunity) and how far did it bounce and how far are hills from crater.
Rob: For opportunity, we're doing a lot of minor changes. Airbag temperatures, other small corrections or changes to parameters not so much based on what we know about what we learned at Gusev but based on how we model Meridiani now that we have real data from Gusev.
Tim: 250m from the rim of the crater. A moderate distance for the crater. Hills nearest point is just under 3km away.
Q. Old saying, any one you can walk away from. Did you really escape disaster because of the cross-wind counter.
Rob: if we had not fired that rocket we would have hit the ground just within the boundary of what we designed for. Glad we didn't have to try it.
Q. Steve, can you run through key things science teams are looking at.
Steve: Atmosphere team looking at mini-TES data looking upward through Mars. We've got so many things that we'd like to show you guys. We have lovely temperature profiles. The geology group and long term planning group have been focused on strategy for first few rocks. Just images of wheel tacks in stereo will be very exciting. In the not too distant future, we're gonna do a little scratch and turn kind of thing with the wheels for science and engineering. Minerology and chemistry group awaiting APSX. Their focus is how to pick drive directions that will maximize our ability to learn about the minerals in the rocks with mini-TES. Need to fill the mini-TES field of view so looking for larger rocks to drive closer to.
Q. Looking at those hills, if you're standing on earth, you'll see a range of hills and it appears that one slopes down behind another. They look like hills on earth. Any possibility that you can work your way through one of those passes?
Steve: yeah, it's a beautiful piece of scenery. I'm not gonna tell you we can't. But again, those things are 5 times farther than Spirit was designed to go.
Q. For Chris, can you take us through what's ahead. A few more turns, some Pancam images? For Rob, lots of discussion for future landers. Stick with airbags?
Chris: Still on schedule for egress for sol 12. Two more turn in place maneuvers. Our first move tomorrow will be another 50 degrees. Last move will be a final 20deg move and turn our wheels straight. That'll all be tomorrow with confirmation from end of day Odyssey pass. Then the next day will be egress. There will be some more focused observations with Pancam and mini-TES before roll off. We already have some additional data from the blind spot and nothing hiding there.
Rob: I've been asked about these EDL systems before. There is no right way to land on Mars. We are still in the infant stage of these systems. It depends on so much. I personally believe that we're going to have a collection of different designs for EDL systems. There are many features of this system that need to be improved. We still can't get to many places on Mars. Places that are very scientifically interesting *and* safe are rare. We'd like to be able to deliver to more locations. We can't go to higher elevations yet. There's a big future out there.
Q. How long are the range of eastern hills, how high are the peeks and any theories about how they formed.
Tim: a few km in length. highest peaks about 100 m tall. three times the height of pathfinder twin peaks. three times as far away though. How they got there? That's difficult. Premature to draw conclusions. Some on science team are speculating about layering in the hills.
Steve: generally speaking, the origin breaks down into categories. One, they existed as before the crater. The other possibility is that material was stripped away to create them. We'll learn more as we go there.
Q. As you get closer to crater it gets more difficult to navigate.
Steve: we expect topography to get rougher and more blocky as we get closer to it. We have some hints from THEMIS on Odyssey. By looking at temps from orbit you can get a sense about how blocky. About 3/4ths of it is more blocky and rockier and one little part, like a door opening in has less of that and that's the part facing us. Good luck. We'll be careful. Darned careful. Whether or not it's important to get right to the rim or not. Hard question. I would expect that the floor will have a lot of drift material.
Tim: there is a suggestion that there are dark and light toned dune fields on the floor of the crater. The topography is rather subdued. They've either been partially buried or stripped away. We don't expect a meteor crater freshness. We're probably looking at a 5m high exterior rim. Who knows. The interior is not as deep as a fresh bowl shaped crater. Could be 10 or 15 m deep.
Steve: We can look at the stuff in the crater walls but we can also look at the stuff in the ejecta blanket.
Q. Biggest concerns as you get ready to get off the lander.
Chris: egress itself. we've tested a number of profiles and established how high a drop we can take. We want to have the best alignment. There are also various hazards along the lander deck.
Q. Tomorrow the president is making a big announcement about other missions, a proposed manned mission to orbit Mars. Thoughts on this?
Rob: it is very exciting. It's a huge road to get there, a long-term adventure. It's all integrated with exploration of Earth, and the science we get from these explorations. People need to have a place to head to focus minds and excitement and this can easily do that.
Q. What are we learning about Mars weather? Modeled for water vapor?
Rob: Mars, like earth has weather. Trick is to make sure you don't have to care about the weather. We had cold air prior to Christmas and then this very significant regional dust storm on the other side of the planet but to our surprise, the atmosphere can get warmer in the upper atmosphere because that higher-level dust can propagate over the entire globe. It's like a little thermal blanket that warms up that layer of the atmosphere. No need to model for
Q. How fast do you move off the lander? Steve, projected range of rover was 600 meters? Enough power as seasons change?
Chris: 3cm per second.
Steve: We have a set of expectations worked out ahead of the project. The number that was set as a target was 600 meters. Most of us are feeling pretty good about that number but 3km is a lot longer than that. It's late summer heading into fall.
Chris: As we get colder we'll use more energy but won't have to shut down to avoid overheating problem. Some predictions put us past the 90 sol mission mark.
