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Spirit (rover)

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MER-A ("Spirit") is the first of the two Mars Exploration Rover Missions. It successfully landed on Mars on January 3, 2004. Its twin, MER-B ("Opportunity"), is expected to land on Mars January 24, 2004.

Note: Days on Mars are called Sols, the landing date (January 3) of MER-A is considered Sol 1, Sol 2 is January 4 and notable as the rover first responded to NASA commands on Sol 2.

Landing Site: Columbia Memorial Station

MER-A landed in Gusev crater about 10 km from the center of the target ellipse at latitude 14.5718° S ± 30 meters, longitude 175.4785° E ± 0.5 meters [1]. A panorama [2] shows a slightly rolling surface, littered with small rocks, with hills on the horizon up to 27 km away. The MER team named the landing site "Columbia Memorial Station", in honor of the seven astronauts killed in the Space Shuttle Columbia disaster.

Events and discoveries

Sleepy Hollow

"Sleepy Hollow," a shallow depression in the Mars ground near NASA's Spirit rover, may become an early destination when the rover drives off its lander platform in a week or so. NASA scientists were very interested in this crater. It is 9 meters (30 feet) across and about 12 meters (40 feet) north of the lander.

File:Sleepyhollowsmall.jpg


First 3-D panorama of landing site: the crater under the sun is "Sleepy Hollow" received on January 5. (Enlarge image)

"Just as the ancient mariners used sextants for 'shooting the Sun,' as they called it, we were successfully able to shoot the Sun with our panorama camera, then use that information to point the antenna," said JPL's Matt Wallace, mission manger.

First color photograph

Below is the first color image of Mars taken by the panoramic camera on the Mars Exploration Rover Spirit. It is the highest resolution image ever taken on the surface of another planet. "We're seeing a panoramic mosaic of four pancam images high by three wide," said camera designer Jim Bell of Cornell. There are actually 12 million pixels in this image, it's 4,000 high by 3,000 wide. This, however, is only the tip of the iceberg, as this image, received on January 6, 2004, is about one eighth of a single pancam panorama and isn't stereo.

Another detailed photograph, this one from the center of the Gusev Crater, showing a mostly flat, reddish expanse, with relatively small greyish rocks littering the field of view, taken by the Spirit rover (NASA)
Part of the first color photograph sent from Spirit. The depression known as "Sleepy Hollow" is visible at the right of this photograph. (Enlarge image)


Adirondack

Adirondack is the rover's first target rock. Scientists chose Adirondack to be Spirit's first target rock rather than another rock, called Sashimi, that would have been a shorter, straight-ahead drive. Spirit traversed the sandy martian terrain at Gusev Crater to arrive in front of this football-sized rock on Sunday, Jan. 18, 2004, just three days after it successfully rolled off the lander. The rock was selected as Spirit's first target because its dust-free, flat surface is ideally suited for grinding. Clean surfaces also are better for examining a rock's top coating. Scientists named the angular rock after the Adirondack mountain range in New York. The word Adirondack is Native American and is interpreted by some to mean "They of the great rocks." Spirit's Moessbauer spectrometer detected a mineral called olivine, which does not survive weathering well. The lack of weathering suggested by the presence of olivine might be evidence that the soil particles are finely ground volcanic material. Another possible explanation is that the soil layer where the measurements were taken is extremely thin, and the olivine is actually in a rock under the soil.


(enlarged image)

Timeline

2003

  • June 6 - June 8 - Two launch attempts cancelled due to weather conditions at Kennedy Space Center.
  • June 10 - MER-A ("Spirit") was successfully launched aboard a Delta II rocket.

2004

  • January 3 (Sol 1) JPL Images from 1/3/2004
    • 20:35 PST - MER-A landed in Gusev crater, however not exactly at its appointed landing spot within the crater (believed by scientists to once have been a crater lake). It later became apparent that the rover had landed six miles downrange from its planned landing site, but has landed in an area possibly even more favorable for the tests scientists want the rover to perform. Three decent images showed its progress as it came down. [3]
    • It returns black and white photographs via a relay through Mars-orbiting satellites.
  • January 4 (Sol 2) JPL Images from 1/4/2004
    • MER-A starts its first day of "work", receiving and responding to commands from NASA.
  • January 5 (Sol 3) JPL Images from 1/5/2004
    • The lander locks on its high-gain antenna and begins transmitting color photographs directly to Earth.
    • The first 3D Stereogram images are sent back from Spirit.
    • Four of five planned tests on scientific instruments on MER-A have been successful, the fifth instrument test is expected to occur later tonight. See Scientific instuments on the rovers.
  • January 6 (Sol 4) JPL Images from 1/6/2004
    • 08:00 PST - U.S. President George W. Bush calls JPL to congratulate the MER team for a successful landing.
    • The first high resolution, full color image is received from Spirit. [4]
    • Throughout the day, a series of high quality color images were sent from Spirit to NASA. During a news conference about the day's events Steve Squyres, science chief of the MER mission said "This is just a tiny taste of what's to come", refering to the first color images coming back.
    • 12:15 PST - The MER team decides to name the specific spot that Spirit landed on within the Gusev Crater "Columbia Memorial Station", in honor of the seven astronauts killed in the disaster. [5]
  • January 7 (Sol 5) JPL Images from 1/7/2004
    • 09:00 PST - Daily news briefing broadcast from JPL over NASA TV. A few new images are released, mainly polished versions of earlier images. Events from Sol 4 are reviewed, including a diagnostic test of a high gain antenna motor voltage spike(which occured on Sol 2), which did not show any problems and was attributed to debris in the antenna machine housing. Airbag retraction was continued on Sol 4. Sol 5 activities are discussed, scientists and engineers on the MER team are anxious to get Spirit separated from its lander and moving around the martian surface.
    • A plot is released by JPL showing the "Dust Optical Depth" of the Gusev Crater and Meridiani Planum areas of Mars. The plot shows a measure of the amount of dust in the martian atmosphere as taken by instruments on the orbiting Mars Global Surveyor satellite. Recent dust storms in December and January on Mars have greatly increased the amount of dust in the atmosphere around Meridiani Planum, the expected landing site of MER-A's sister rover Opportunity, landing 1/24/2004. It is unknown at this point if this increased dust activity will hinder Opportunity's mission. [6]
  • January 8 (Sol 6) JPL Images from 1/8/2004
    • 09:00 PST - Daily news briefing from JPL, apparently the activities to further retract the airbag under Spirit's lander were unsuccessful. On Sol 6 JPL engineers will try 6 rotations to try and force the partially deflated airbags fully under the lander. If this attempt fails, Spirit may have to turn itself around on the lander and attempt egress via another route.
    • Engineers will also begin Spirit's two step lifting process to "stand up" on the lander. Step 1 is to raise Spirit up on its back 4 wheels, and Step 2 is to deploy the currently retracted front wheels.
    • It is predicted that the airbag problem will delay Spirit's egress from the lander to January 14 or later. Currently the plan is to lift landing petal on the lander that Spirit is preparing travel down and attempt to tuck the excess airbag material under the petal. [7]
  • January 9 (Sol 7) JPL Images from 1/9/2004
    • During the night of Sol 6 Spirit successfully completed parts one and two of the "stand up" operation and now has its front wheels deployed and is almost ready to egress. Parts three and four of the stand up operation will be executed tonight. [8]
    • Images of data from Spirit's Mini-TES were released [9]
    • Another attempt to pack the inflated airbags under the ramp petals of the lander failed. Now JPL engineers will attempt to turn the rover around while still on the lander and egress down one of the other ramps on the lander. This activity has been practiced before MER mission launch and is expected to work.
  • January 10 (Sol 8) JPL Images from 1/10/2004
    • The Spirit Rover completed its stand up operation and is now standing with all six wheels deployed and locked, with one final connection between the lander and Spirit remaining.
  • January 11 (Sol 9) JPL Images from 1/11/2004
    • At the conclusion of Sol 8 the Spirit Rover's science arm, which features tools for digging into and taking close up images of rocks, was moved from its stowed launch position to its forward "drive" position.
  • January 12 (Sol 10) JPL Images from 1/12/2004
    • During Sol 9 the Spirit Rover performed science activities and returned data from the Pancam, completing the 360 panoramic image it took of its surroundings last week. Mini-TES data suggests more evidence that the Gusev site may have been a water filled lake.
    • Engineers plan the egress operation Spirit will begin on Sol 10 using a replica of the Spirit rover and lander. The tests go well, and no problems are expected.
  • January 13 (Sol 11) JPL Images from 1/13/2004
    • Sol 10 activities included successfully cutting the last link between the Spirit rover and lander. The first 45 degree turn was successful and the rover is preparing for egress. On Earth, mission details for the rover's exploration of the martian surface are being planned now that it is known exactly where Spirit is within Gusev.
  • January 14 (Sol 12)
  • January 15 Images from 1/2/2004
    • Spirit leaves the launch vehicle.
  • January 16
    • A 3-D perspective image [10] is taken by the panoramic camera onboard the Mars Exploration Rover Spirit showing "Adirondack," the rover's first target rock.
  • January 20 Images from 1/20/2004
    • NASA Mars Rover’s First Soil Analysis Yields Surprises Among these suprises, is the detection of olivine, which does not survive weathering well.
  • January 21 (Sol 18) Spirit stops transmitting data and no longer responds to commands.
  • January 22 (Sol 19)
    • The rover radioed a 7.8 bps beep Thursday morning confirming that it had received a transmission from Earth. The 7.8 bps indicates that the spacecraft believes it's in a fault mode. Still, it has not returned any data since early Wednesday. Flight-team engineers for NASA's Mars Exploration Rover Project are working to diagnose the cause of communications difficulties.
    • Pete Theisinger at the Jet Propulsion Laboratory in Pasadena, Calif., described the situation as "a very serious anomaly." He did say however that "If this problem on Spirit is somehow a software corruption issue, or memory corruption issue that's reflecting itself in software, and there's not a serious power fault, Spirit can go for quite a long time and we can pick up the pieces again."
    • Steve Squyres, the Cornell astronomy professor who heads the Mars mission's science team, said "It's cause for concern, certainly, but it's not cause for alarm. I've been in this business for almost 25 years now, and I've been involved in over a dozen different planetary missions. I don't know of a single one that hasn't had a problem like this somewhere along the line, and I include in that list missions like Voyager and Magellan that were spectacular successes. This kind of thing is part of the business of operating complicated spacecraft far from Earth." He continued stating that "This vehicle knows how to protect itself when something goes wrong, and can do so for long periods of time." He concluded saying "I'm very optimistic that we'll get this straightened out, and get back to the business of exploring Gusev crater."
    • The NASA team plans to instruct the craft to send back engineering data from Spirit's onboard memory (for diagnostic purposes) and possibly send commands to restore normal communication at around 6 a.m. EST tommorow.
    • On NASA Television, JPL Director Charles Elachi said "We are cautiously encouraged," and added "It is a pretty smart machine that we have up there and the key thing that we are going to do next is to communicate with it tomorrow morning and ask it to send us some data down so we can do a diagnostic of what's the problem"
  • January 23
    • NASA's Spirit rover communicated with Earth in a signal detected by NASA's Deep Space Network antenna complex near Madrid, Spain, at 12:34 Universal Time (4:34 a.m. PST) this morning. The transmissions came during a communication window about 90 minutes after Spirit woke up for the morning on Mars. The signal lasted for 10 minutes at a data rate of 10 bits per second. Mission controllers at NASA's Jet Propulsion Laboratory, Pasadena, Calif., plan to send commands to Spirit seeking additional data from the spacecraft during the subsequent few hours. [11]
    • The flight team for NASA's Spirit received actual data from the rover in another communication session that began at 13:26 Universal Time (5:26 a.m. PST) and lasted 20 minutes at a data rate of 120 bits per second. [12]
  • At a news briefing, Pete Theisinger said, "The software is in X-band fault mode. We surmise it got there because of some problem with the high-gain antenna pointing, and that is why the second high-gain antenna pass on Wednesday did not work. It gives us a little bit of a tale-tell for what is going on with the processor now. But as I pointed out to you, the flight software is not functioning normally. The two times we have gone and communicated with the system, we have gotten different flight software behaviors. Therefore we do not have assurance the next time we go and ask for it we will get either one of those two behaviors or perhaps a third behavior. " Later Theisinger said that the Spirit is in "critical condition" and stated that "We do not know to what extent we can restore functionality to the system because we don't know what's broke. We don't know what started this chain of events. I think, personally, that is a sequence of things. And we don't know, therefore, the consequences of that. I think it is difficult, at this very preliminary stage, to assume that we did not have some type of hardware event that caused this to start. Therefore, we don't know to what extent we can work around that hardware event and to what extent we can get the software to ignore that hardware event, if that is what we eventually have to do. "

References

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