I cleaned up my notes from this morning's press conference. I still haven't had my coffee so I don't expect a Pulitzer for this but figured some of you might be interested. Again, I'm not a fast enought typist to do a real transcription and much of this is paraphrasing so don't quote these folks based on my notes. (ugly spellcheck problem fixed. thanks Joe.)
Jennifer Trospar:
Engineering has done analysis of the data from last night.
Rover is currently asleep and will wake up around noon for an Odyssey pass. Around 2:30 PM we'll play our good morning song and wake up the rover.
We're completing our assessment of the thermal environment. Initial assessments said the hardware on the outside of the rover was warmer than we expected and so we think the temperature is 10 percent warmer than we had predicted. Because of the tau, temperatures are more moderate (the hot of the day is less hot and the cools are less cool). Overall this is a good thing but it can have impact on the solar cells charging of the batteries. Today's main goal is to get the high gain antenna deployed. We have a minor problem with occultation with the pancam mast. When the earth is at 30 degrees, the position we want to be in for the high gain antenna to transmit, the pancam mast is in eh way so we've been working overnight to flip the high gain so we don't have to worry about the pancam mast blocking it. ACS is good but we have to work around that.
Assessment of mechanical systems: We saw that they actually look very good. We didn't see any current readings that would indicate pulling in any rocks. in one case something that looked like a rock last night might be an airbag.
Imaging: downlinked 60 of 64 images. Imaging system is functioning nominally. Prior to uhf pass we collected one image and after that the vehicle did some more pancam imaging and those missed last night's pass and are in this morning's MGS data but not yet processed.
Power: last night someone asked about the solar array current being less than predicted. That seems to be the case and that's where this tau was more than predicted so we are getting a little bit less current from solar arrays. We'll have a better estimate of just how much less at 2:42 when the batteries reach a set level and the rover wakes up.
Communications: 6 megabits from MGS pass (this morning?)
Egress assessment: We believe that we're facing south, 9 degrees off of south pointing slightly east. We'll tell the spacecraft those numbers to help it with its sunfind later today. We looked at the airbags and we believe that both the airbags are above the egress aid and what we thought is probably not a rock. These are poor resolution images, though, 2 bits per pixel 256x256 images. We'll take some full frame 8 bits per pixel images today to determine if that's a rock or a darkened patch of airbag. The front deck height is 37 centimeters. We've never had an opportunity to egress off such a low height. The egress path is the straight off egress. In a basedown landing case we don't want to be that high so we don't retract the base petal airbag as much. We'll leave that, retract the side petal airbags, hopefully without moving the petals.
Matt Wallace:
Engineering activities: We've been making efforts to establish our heading to be able to accurately point the antenna. We are able to sense the rotation of the planet and since we know what latitude we're at, we can come up with a heading. We've been doing analysis of shadows and that's helped too. Steve will talk about exactly where we are in that ellipse. We can also use features on the horizon to help us better understand our heading. Because we landed facing south, the imaging mast is in the way of the high gain antenna beam. We're testing the sequence of commands to flip the antenna around to avoid that interruption. We hope to be able to uplink that command today. We're doing more imaging to better understand the position of the airbags. The rover continues to be healthy. We're trying to prepare some of our mechanisms for follow on activities tomorrow on sol 3 when we'll start unfurling the rover in prep for standup and egress.
Steve Squyres:
Science activities: Just as i think any explorer would do, the science team has been focused on where we are and where we're gonna go. We have a number of ways we can tell where we are. The science team has been focused on looking at images from DIMES (Descent Image
Motion Estimation Subsystem). it worked perfectly to figure out if wind was moving us and when it determined that was the case, signaled to fires the mini retro rockets that straightened us up for landing. It also provided pictures on the ground and we almost immediately spotted some features on the ground that we recognized from THEMIS and MOC images. We have Three dimes images. The last of the three has (1200 meters altitude estimated) shows a heavily cratered surface. This image was taken seconds before touchdown. Exactly where we are in the image you can't tell by looking at the image because we bounced, but we know we're in this image. The team is looking at hills to match them up against landmarks. (Here he compared the DIMES image with a THEMIS image). "We hit the sweet spot." Mother nature has cleared off the rocks for us. See the dust devil tracks. We've landed right in a place with dust devil tracks. We know with great certainty that we're absolutely in the place where we want to be in Gusev. "We're in a marvelous place".
What are we gonna do when we drive off the lander. It's going to take 8 or 9 sols to get this vehicle safely off. The science team is thinking about what will come next. We're anxious to get the arm out. The first thing we plan to do in the first few sols (cautiously) is to put the arm out and look at whatever's in front of us after the egress drive. The polar panorama view shows some of the rocks in front of us. If we drive off in the forward direction, terrain in front of us is littered with ricks. We'll probably drive forward about 3 meters. We may have both soil and rocks within reach of the arm we'll get measures on soil and rock without moving the rover after the egress park. We probably won't use the RAT but we could use the , mossbauer spectrometer, the microscopic imager, APX imager. I don't know where we're going to drive yet. The egress drive will be based solely on safety. Once we've done that we're gonna get the arm out and look immediately in front of us. Then look to more distant travels. Once we've got our exact location there might be some wonderful feature that we find out is within range that will tempt us. If that happens then that may be the direction we'll go. The other possibility are these very strange looking depressions. The lip of nearest depression exposes some rocks in a very interesting way. We've got pictures 14 times sharper coming soon (pancam better than navcam). That depression may be a tantalizing place to go. We don't know what the texture of that stuff. I don't know for sure that it's not a rover trap. (don't want to sink into it) we're gonna tread carefully. Science activities on the current sol is health checks, mossbauer, apxs, microscopic imager, mini-TES plus we want to get the "postcard" image taken, sent, and processed. It will be a truly spectacular image. It'll be taken this afternoon and will come down on one of the subsequent UHF passes. One last thing. I got a congratulatory call from Beagle 2 Colin Pillinger. They're still holding out hope of contacting Beagle 2. I haven't given up on Beagle 2. I told him that "a whole bunch of people on this side of the Atlantic are rooting for you."
Brian Tortock:
DIMES and EDL reconstruction people have given us an estimate. We are less than 10 km from the center of the ellipse. In the days ahead we'll be using Spirit data (some direct and some via Odyssey) to get the lander location.
Q. Jennifer, beyond today what will rover do before egress?
Jennifer: Today we'll focus on the high gain antenna. Tomorrow start the standup. Wheels are folded in so first thing we do as part of standup (tomorrow or delayed a day based on airbags) is to lift up the rover from its belly using a lead screw and deploy the wheels and get the rover standing stable. Standup takes two days then we release wheels. Then we'll release the IDD and move it from the travel position into stowed position. Then final releases and cable cutter. Then egress "bump" (short drive). Then egress drive on sol 9 or sol 10.
Q. 2:42 this afternoon the sun should charge enough to wake up rover. What's the plus or minus minutes based on the new tau estimates.
Jennifer: Assuming a tao of .9 then we should wake up at 2:42. We could wake up 40 minutes sooner.
Q. Who took that picture.
Steve: THEMIS.
Q. The ridges off to the lower right, can you correlate those?
Steve: Those are certainly among the landmarks that people will be looking at to pinpoint our position. Guys on my team are arguing vigorously. They'll have it settled very soon.
Q. The "press science team" (smiles) has begun their "analysis" They're convinced that they can see a huge amount of 3-D details.
Steve: Just wait! We've got stereo pancam, stereo navcam images coming. There is structure, there's plenty of it. It will be revealed in all its glory in the next several days.
Q. Jennifer, can you explain tau. Steve, how far away is that depression.
Jennifer. Tau is related to dust in the atmosphere from dust storms. If it impacts the mission, then it gives us a little less energy margin. We've planned our activities with enough margin that this amount of change won't affect the egress. Once we're into science, then clearly if we're getting less energy then there will be a little bit less for the science. We can do trades, for example, do one less comm pass and a little more driving.
Steve: We don't know the exact distance of the depression. I was just talking with the team and it's still rumor and hearsay but the number I heard was 30 meters but don't take that to the bank. A couple tens of meters or something like that. We'll have a good number soon.
Q. Gross comparison between this site and pathfinder Viking?
Steve: Easier to drive on. Too early to talk about the composition, we don't have color images yet. It's too early to talk about the texture, we don't have the high resolution images yet. So we're talking about population now. We're seeing a surface that is remarkably devoid of big boulders and that's glorious news because big boulders are hard to drive over. If you look at the Pathfinder site, you'd have a hard time driving around parts of that. I'd say we nailed it (finding a good sight to drive on).
Q. Is that (pointing out a feature on the image) a playa?
Steve: It's playa-looking but it's not a playa. I'll be willing to bet that it's something that's been filled in very recently with fine grained dust. Fine stuff has been swept away exactly consistent with the THEMIS images showing all the dust devil tracks. We're left with lag deposit of courser grained materials. These hollows or depressions look to contain significant amounts of dust but we don't have the big "dunes" that would make driving difficult. This is a "great place to drive"
Q. Is this dust devil season? Concerned?
Steve. Martian wind is not something to be concerned about. It's less than 1% the pressure on earth. This is a big rover. The chances of a dust devil coming around and flipping over our rover: "ain't gonna happen." Guys on my team are talking about making a dust devil movie. Dust devil time of day early afternoon hours, noon, one, two o'clock. It's not really a season but a time of day. They've done us a favor cleaning off rocks and I'd like to catch one in the act.
Q. How to determine if you can safely enter one of those depressions.
Steve: We're dealing with low res now but we're gonna have better images and the morphology when shown to an experienced geologist should tell us more. Another technique is that we may be able to use mini-TES which can measure temperature. You can learn about density by measuring temperature at different times of day. You know when you're at the beach and it's mid-day and the sand is hot, you can jump to rocks and they're cool. In the evening, the opposite, the sand is cool and the rocks are warm. Also, "you can drive up and dip your toe in and see what happens".
Q. Wakeup calls.
Jennifer: The flight director will (as per the tradition) play the song selected for the day then do the wakeup call.
Steve: "Don't worry be happy" played last night during the landing sequence.
Q. What time will we get the "postcard". Is that notch in the horizon a mosaic artifact?
Steve: pancam postcard 11:30 tonight at the earliest. Mars odyssey afternoon flyover (late tonight) is the first shot. 3 UHF passses have performed well but we don't know. Yes, it's artifacts of big blow-up of a low res image.
Q. Everything looks good on the lander? Have you done tests of things? Can you elaborate on the condition of the lander and the rover. (The Reuters guy seems a bit lame)
Brian: We do regular detailed assessments. We have models to validate all of the numbers. We have teams of experts. Each time we do a comm pass we look at each of the subsystems, power, thermal, software, etc. This is an extremely healthy rover system.
Posted by asa at January 4, 2004 10:03 AM