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  BY JUSTIN RAY Follow the landing of NASA's "Spirit" Mars Exploration Rover-A on the Red Planet! Reload this page for the very latest on the mission.
THURSDAY, FEBRUARY 26, 2004
2215 GMT (5:15 p.m. EST)
The rover will study the soil in its current location before approaching a rock called "Humphrey" for observations and then using the Rock Abrasion Tool to grind into it. Opportunity continues to use its Mossbauer Spectrometer to look for iron-bearing minerals in the RAT hole it carved at the bedrock outcropping. The data from the first Mossbauer spectrum of hole was received on Earth Wednesday afternoon. The Alpha Particle X-ray Spectrometer data from yestersol at this target was retransmitted to Earth again Wednesday to get missing packets of data that were not received during the first data communications relay, NASA said. Opportunity also snapped pictures of the rock areas named "Maya" and "Jericho" with the panoramic camera and took Miniature Thermal Emission Spectrometer measurements of the sky and "El Capitan" throughout the sol. On Thursday evening (U.S.) time, Opportunity will make a short move (10 to 20 centimeters or 4 to 8 inches) to the next Rock Abrasion Tool target site called "Guadalupe." Meanwhile, controllers are changing their communications plans with Opportunity due to power considerations. "The amount of power Opportunity is able to generate continues to dwindle due to the decreasing amount of sunlight (energy) reaching the solar panels during the Martian seasonal transition to winter. Because of this, the engineers are adjusting the roverŐs daily communications activities. To minimize power use for communications sessions, engineers began a new "receive only" morning direct-from-earth communication relay. This lower-power communication mode was successful. Opportunity will continue with this approach to maximize the available power for driving and science activities as Mars moves farther away from Earth and the Sun in its elliptical orbit. "In conjunction with the morning communications session change, engineers added a second afternoon Mars Odyssey orbiter relay pass, which uses less power in transmitting data volume than direct-to-Earth communication. This additional Odyssey pass more than compensated for the elimination of the morning direct-to-Earth downlink. Engineers also continue to effectively use rover 'naps' throughout the day to maximize energy savings."
WEDNESDAY, FEBRUARY 25, 2004 Meanwhile, Opportunity had a light work day. It was awake for only three hours during the daytime to relay data to Earth and then slept through the afternoon to recharge its batteries, Cook said. The rover has been using its instruments to probe the RAT hole during the night, including multi-hour observations with the Mossbauer Spectrometer, Cook reported. "The rover has been doing a lot of science work at night, and the season on Mars is changing to winter, so the rover has less energy to work with than it did earlier in the mission. The Martian days are getting shorter and the sun angle is not allowing either rover to power up the solar panels as much as in the past," NASA says. A full press conference is scheduled for 1 p.m. EST (1700 GMT) on Thursday for officials to give a full update on the rovers and their science activities.
TUESDAY, FEBRUARY 24, 2004
The science instruments will study the RAT hole over the next couple of days to determine if the rock's interior has the same composition and minerals as the outer surface. Scientists are trying to figure out what the exposed bedrock outcropping is made of. Spirit finished its work at the trenching site and has driven about 50 meters in the past two days, reaching an area called "Middle Ground." It will be studying this region before continuing to move up to Bonneville Crater's rim.
SUNDAY, FEBRUARY 22, 2004
Opportunity is using its arm to make close-up inspections of the "El Capitan" part of the street-curb-sized outcrop in the crater where the rover is working. Opportunity took 46 pictures with its microscope, examining several locations on "El Capitan" at a range of focal distances, NASA reported. The Mossbauer Spectrometer and Alpha Particle X-ray Spectrometer studied the rock to assess what minerals and elements are present. On Monday, Opportunity is scheduled to use the Rock Abrasion Tool to grind into part of El Capitan, giving the science devices a port hole to determine if the rock's interior is the same as the exterior. Meanwhile, Spirit has spent a couple of days probing the wheel-dug trench nicknamed "Road Cut." Using the science instruments on its arm, the rover is collecting data about the subsurface soil exposed by the hole. A series of microscopic images of the trench floor and walls have also been obtained. Spirit is preparing to resume driving to Bonneville Crater. The next news conference on NASA Television is Thursday.
FRIDAY, FEBRUARY 20, 2004 The science observations will be performed over the next couple of days, studying the trench floor and wall. Spirit resumes its drive on the road to Bonneville Crater Monday. Meanwhile, Opportunity finished studying its trench and drove 15 meters (50 feet) on the last workday, the longest drive that rover has made to date. Dodging the trench and lander, Opportunity cruised to nearly the opposite side of the crater to the bedrock outcrop, Erickson said. The rover is doing soil studies today, then moving three-tenths of a meter forward to get its arm within reach of the El Capitan area of the outcrop to begin a detailed study.
THURSDAY, FEBRUARY 19, 2004
By inspecting the sides and floor of a hole it dug on Mars, NASA's Opportunity rover is finding some things it did not see beforehand, including round pebbles that are shiny and soil so fine-grained that the rover's microscope can't make out individual particles. "What's underneath is different than what's at the immediate surface," said Dr. Albert Yen, rover science team member at NASA's Jet Propulsion Laboratory, Pasadena, Calif. Meanwhile, NASA's other Mars Exploration Rover, Spirit, has reached a site with such interesting soil that scientists have decided to robotically dig a hole there, too. Spirit's trenching at a shallow depression dubbed "Laguna Hollow" could answer questions about whether traits on the soil surface resulted from repeated swelling and shrinking of an upper layer bearing concentrated brine, among other possibilities. Opportunity has manipulated its robotic arm to use its microscope on five different locations within the trench the rover dug on Monday. It has also taken spectrometer readings of two sites. "We've given the arm a very strenuous workout," said JPL's Dr. Eric Baumgartner, lead engineer for the arm. The accuracy of the tool placements -- within 5 millimeters, or less than a quarter inch -- is remarkable for mobile robotics on Earth, much less on Mars. Once data are analyzed from the alpha particle X-ray spectrometer and the Moessbauer spectrometer about what elements and what iron-bearing minerals are present, the differences between the subsurface and the surface will be easier to interpret, Yen said. While Opportunity has been digging and examining its trench this week, it has also been catching up on transmission of pictures and information from its survey last week of a rock outcrop along the inner wall of the small crater in which the rover is working. Both rovers can communicate directly with Earth, but JPL's Andrea Barbieri, telecommunication system engineer, reported that 66 percent of the 10 gigabits of data they have returned so far has come via relays by NASA's Mars Odyssey orbiter and another 16 percent via relays by NASA's Mars Global Surveyor. Based on the outcrop survey, scientists have chosen a feature they have dubbed "El Capitan" as the next target for intensive investigation by Opportunity. "We've planned our assault on the outcrop," said Dr. Steve Squyres of Cornell University, Ithaca, N.Y., principal investigator for the rovers' science instruments. "The whole stack of rocks seems to be well exposed here," he said of the chosen target. Upper and lower portions appear to differ in layering and weathering characteristics. Planners anticipate that Opportunity's arm will be able to reach both the upper and lower parts from a single parking spot in front of "El Capitan." Halfway around the planet, Spirit will be told to use a front wheel to dig a trench during the martian day, or "sol," that will end at 12:36 p.m. Friday, PST. Some soil in "Laguna Hollow" appeared to stick to Spirit's wheels. Possible explanations include very fine-grained dust or concentrated salt making the soil sticky, said Dr. Dave Des Marais, a rover science team member from NASA Ames Research Center, Moffett Field, Calif. Pictures of the surface there also show pebbles arranged in clusters or lines around lighter patches Des Marais described as "miniature hollows." This resembles patterned ground on Earth that can result from alternating expansion and shrinkage of the soil. Possible explanations for repeated expanding and contracting include cycles of freezing and thawing or temperature swings in salty soil. After trenching to seek clues about those possibilities, Spirit will continue on its trek toward the rim of a crater nicknamed "Bonneville," now estimated to be about 135 meters (443 feet) away from the rover. Spirit has already driven 128 meters (420 feet). The rovers' main task is to explore their landing sites for evidence in the rocks and soil about whether the sites' past environments were ever watery and possibly suitable for sustaining life.
1830 GMT (1:30 p.m. EST)
Meanwhile, Spirit is using its full suite of instruments to study a depression called Laguna Hollow. The rover is preparing to do a trenching in this hollow. Check back a little later for a full report from today's rover science news conference.
WEDNESDAY, FEBRUARY 18, 2004
1845 GMT (1:45 p.m. EST)
"We did a fairly complicated, probably the most complicated ever, set of Microscopic Imager observations of the trench that we have dug as well as getting the Mossbauer and APXS down there where they can do some observations overnight," Richard Cook, rover project manager, told reporters in a teleconference today. "We have also done a little bit of long-distance remote sensing observations with the Mini-TES and Pancam looking over at the target that we probably are going to go to on the rock outcropping called El Capitan. So that information was acquired and sent to the ground as well. "The plan for today is actually to do more of the same. They find the inside of this trench to be quite interesting, so the scientists want to spend another day doing another set of observations. Then we will probably start driving to El Capitan tomorrow at the earliest. In fact, it might even be delayed another day if they decide to drive around and look at this trench from the other side, which apparently there is some discussion of doing." Meanwhile, Spirit has reached the midway point of its primary mission. It is completing the Sol 45 workday on Mars. "Things continue to go well," Cook says. Late last night/early this morning (U.S. time), the rover used its science arm to examine the spot reached the day before. Then Spirit resumed driving, moving to a flat depression called Laguna Hollow. It will remain there a day doing science measurements before making an approximate 40-meter drive Friday morning on the trek to Bonneville Crater. Engineers believe the rovers will last well beyond their 90-day primary mission, allowing the craft to enter extended missions to continue exploring their respective landing locations on the opposite sides of Mars. The next NASA news conference is scheduled for 1 p.m. EST on Thursday.
TUESDAY, FEBRUARY 17, 2004
Proving to be a real Mars hotrod, the Spirit rover has become the most traveled vehicle on the Red Planet, surpassing the distance accumulated by the Pathfinder rover nearly seven years ago. Read our full story.
2245 GMT (5:45 p.m. EST)
NASA's Mars Exploration Rover Opportunity has scooped a trench with one of its wheels to reveal what is below the surface of a selected patch of soil. "Yesterday we dug a nice big hole on Mars," said Jeffrey Biesiadecki, a rover planner at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The rover alternately pushed soil forward and backward out of the trench with its right front wheel while other wheels held the rover in place. The rover turned slightly between bouts of digging to widen the hole. "We took a patient, gentle approach to digging," Biesiadecki said. The process lasted 22 minutes. The resulting trench -- the first dug by either Mars Exploration Rover -- is about 50 centimeters (20 inches) long and 10 centimeters (4 inches) deep. "It came out deeper than I expected," said Dr. Rob Sullivan of Cornell University, Ithaca, N.Y., a science-team member who worked closely with engineers to plan the digging. Two features that caught scientists' attention were the clotty texture of soil in the upper wall of the trench and the brightness of soil on the trench floor, Sullivan said. Researchers look forward to getting more information from observations of the trench planned during the next two or three days using the rover's full set of science instruments. Opportunity's twin rover, Spirit, drove 21.6 meters closer to its target destination of a crater nicknamed "Bonneville" overnight Monday to Tuesday. It has now rolled a total of 108 meters (354 feet) since leaving its lander 34 days ago, surpassing the total distance driven by the Mars Pathfinder mission's Sojourner rover in 1997. Spirit has also begun using a transmission rate of 256 kilobits per second, double its previous best, said JPL's Richard Cook. Cook became project manager for the Mars Exploration Rover Project today when the former manager, Peter Theisinger, switched to manage NASA's Mars Science Laboratory Project, in development for a 2009 launch. Spirit's drive toward "Bonneville" is based on expectations that the impact that created the crater "would have overturned the stratigraphy and exposed it for our viewing pleasure," said Dr. Ray Arvidson of Washington University in St. Louis, deputy principal investigator for the rovers' science instruments. That stratigraphy, or arrangement of rock layers, could hold clues to the mission's overriding question -- whether the past environment in the region of Mars where Spirit landed was ever persistently wet and possibly suitable for sustaining life. Both rovers have returned striking new pictures in recent days. Microscope images of soil along Spirit's path reveal smoothly rounded pebbles. Views from both rovers' navigation cameras looking back toward their now-empty landers show the wheel tracks of the roversŐ travels since leaving the landers. Each martian day, or "sol" lasts about 40 minutes longer than an Earth day. Opportunity begins its 25th sol on Mars at 10:59 p.m. Tuesday, PST. Spirit begins its 46th sol on Mars at 11:17 a.m. Wednesday, Pacific Standard Time. The two rovers are halfway around Mars from each other.
1820 GMT (1:20 p.m. EST)
Meanwhile, Spirit used its arm last night to study the surface at its latest parking spot, then drove over 20 meters. The rover has now traversed 108 meters on Mars, breaking the previous record of 102 meters set in 1997 by the Mars Pathfinder rover called Sojourner. We'll have a full report and video from today's news conference later this afternoon.
MONDAY, FEBRUARY 16, 2004 Late tonight (U.S. time), Spirit will use its arm to "touch and feel" the current location. Then it will make a short drive over a two-hour period, mission manager Jim Erickson said. On Tuesday night, the rover is expected to perform up to 50 meters of driving. On Opportunity, the rover today will dig a shallow trench so its suite of mineral and elemental instruments can examine the soil at a site dubbed "Hematite Slope." The rover will lock one wheel in place and use its other five wheels to move a short distance. This procedure should create a two-and-a-half foot long, six-inch wide trench, Erickson said. The arm will examine the trench tomorrow, followed by remote sensing work with the panorama camera and Mini-Thermal Emission Spectrometer on Wednesday. Two news conferences are scheduled on NASA Television this week -- Tuesday and Thursday at 1 p.m. EST.
SUNDAY, FEBRUARY 15, 2004 The rover is about 270 meters from the crater. A 25-meter drive in planned for during the morning of its next workday and possibly another 25 meters later in the day, Erickson said. The goal is to reach the crater in about 18 days, with some additional science stops expected between now and then. Meanwhile, the Opportunity rover has reached the spot inside its small crater where it will perform a trenching job to dig a hole for soil studies. The soil is being examined today in preparation for the digging. The trenching is planned for tomorrow, followed by science investigations on Tuesday. Also today, Opportunity's thermal emission spectrometer is looking up and a similar device on the orbiting Mars Global Surveyor spacecraft is looking down for joint atmospheric studies.
FRIDAY, FEBRUARY 13, 2004
The instrument arm was deployed to use the Alpha Particle X-Ray Spectrometer, Microscopic Imager and Mossbauer Spectrometer, mission manager Matt Wallace said. Tonight, Spirit moves to a flaky-looking rock called "Mimi." You can see an image of the rock here. Scientists say Mimi is different than any other rock seen at the Gusev Crater landing site. Its flaky exterior could have been caused by pressure -- either through burial or impact -- or may have once been a dune that was cemented into flaky layers, scientists say. "The science community liked what they saw in Mimi and wanted to get a closer look," Wallace said. Spirit has a long-term goal of reaching the Bonneville Crater in the distance. After the ongoing science activities are completed, rover will resume the drive Sunday night. On the other side of Mars, Opportunity is completing study at the third of three observation points along the bedrock outcropping. The rover is headed a bit south of its current position during a 9-meter drive to another spot where it will spend three days for soil studies, Wallace said. The craft will dig a shallow hole with its wheels in a patch of hematite-rich soil, allowing the science devices to examine the trench. Opportunity was sent to the Meridiani Planum region of Mars to search for hematite -- a mineral that usual forms in the presence of water.
THURSDAY, FEBRUARY 12, 2004 It will spend the next day doing some science research before resuming the drive, he said. On Opportunity, the rover has driven from the Bravo to Charlie location along the rock outcropping. A map of the cruise is available here. In the coming days, Opportunity will use one of its wheels to dig a hole for soil studies.
WEDNESDAY, FEBRUARY 11, 2004
TUESDAY, FEBRUARY 10, 2004
MONDAY, FEBRUARY 9, 2004
NASA's Spirit rover has begun making some of its own driving decisions while its twin, Opportunity, is presenting scientists with decisions to make about studying small spheres embedded in bedrock, like berries in a muffin. Both rovers are on the move. Late Sunday, Spirit drove about 6.4 meters (21 feet), passing right over the rock called "Adirondack," where it had finished examining the rock's interior revealed by successfully grinding away the surface. The drive tested the rover's autonomous navigation ability for the first time on Mars. "We've entered a new phase of the mission," said Dr. Mark Maimone, rover mobility software engineer at NASA's Jet Propulsion Laboratory, Pasadena, Calif. When the rover is navigating itself, it gets a command telling it where to end up, and it evaluates the terrain with stereo imaging to choose the best way to get there. It must avoid any obstacles it identifies. This capability is expected to enable longer daily drives than depending on step-by-step navigation commands from Earth. Tonight, Spirit will be commanded to drive farther on a northeastward course toward a crater nicknamed "Bonneville." Over the weekend, Spirit drilled the first artificial hole in a rock on Mars. Its rock abrasion tool ground the surface off Adirondack in a patch 45.5 millimeters (1.8 inches) in diameter and 2.65 millimeters (0.1 inch) deep. Examination of thefreshly exposed interior with the rover's microscopic imager and other instruments confirmed that the rock is volcanic basalt. Opportunity drove about 4 meters (13 feet) today. It moved to a second point in a counterclockwise survey of a rock outcrop called "Opportunity Ledge" along the inner wall of the rover's landing-site crater. Pictures taken at the first point in that survey reveal gray spherules, or small spheres, within the layered rocks and also loose on the ground nearby. NASA now knows the location of Opportunity's landing site crater, which is 22 meters (72 feet) in diameter. Radio signals gave a preliminary location less than an hour after landing, and additional information from communications with NASA's Mars Odyssey orbiter soon narrowed the estimate, said JPL's Tim McElrath, deputy chief of the navigation team. As Opportunity neared the ground, winds changed its course from eastbound to northbound, according to analysis of data recorded during the landing. "It's as if the crater were attracting us somehow," said JPL's Dr. Andrew Johnson, engineer for a system that estimated the spacecraft's horizontal motion during the landing. The spacecraft bounced 26 times and rolled about 200 meters (about 220 yards) before coming to rest inside the crater, whose outcrop represents a bonanza for geologists on the mission. JPL geologist Dr. Tim Parker was able to correlate a few features on the horizon above the crater rim with features identified by Mars orbiters, and JPL imaging scientist Dr. Justin Maki identified the spacecraft's jettisoned backshell and parachute in another Opportunity image showing the outlying plains. As a clincher, a new image from Mars Global Surveyor's camera shows the Opportunity lander as a bright feature in the crater. A dark feature near the lander may be the rover. "I won't know if it's really the rover until I take another picture after the rover moves," said Dr. Michael Malin of Malin Space Science Systems, San Diego. He is a member of the rovers' science team and principal investigator for the camera on Mars Global Surveyor. Opportunity's crater is at 1.95 degrees south latitude and 354.47 degrees east longitude, the opposite side of the planet from Spirit's landing site at 14.57 degrees south latitude and 175.47 degrees east longitude. The first outcrop rock Opportunity examined up close is finely-layered, buff-colored and in the process of being eroded by windblown sand. "Embedded in it like blueberries in a muffin are these little spherical grains," said Dr. Steve Squyres of Cornell University, Ithaca, N.Y., principal investigator for the rovers' scientific instruments. Microscopic images show the gray spheres in various stages of being released from the rock. "This is wild looking stuff," Squyres said. "The rock is being eroded away and these spherical grains are dropping out." The spheres may have formed when molten rock was sprayed into the air by a volcano or a meteor impact. Or, they may be concretions, or accumulated material, formed by minerals coming out of solution as water diffused through rock, he said. The main task for both rovers in coming weeks and months is to explore the areas around their landing sites for evidence in rocks and soils about whether those areas ever had environments that were watery and possibly suitable for sustaining life.
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On the other side of Mars, Opportunity stowed its science arm and began slowly driving along the exposed bedrock earlier today. The outcrop has been named "Opportunity Ledge." Meanwhile, an incredible image taken by Opportunity has revealed the parachute and backshell from its descent module sitting on the gray plains outside the tiny crater where the rover landed. See the image here. Opportunity snapped a picture of the hardware after climbing up the side of the crater over the weekend. Also today, navigation experts have announced their report on exactly where Opportunity landed. We'll post a full story later today.
SUNDAY, FEBRUARY 8, 2004
SATURDAY, FEBRUARY 7, 2004
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Meanwhile, Opportunity took more microscopic images of soil and finished its drive to the Snout rock, mission manager Matt Wallace said. Tomorrow, the rover will deploy its arm to begin studying its first target rock. We'll post a full report later today.
FRIDAY, FEBRUARY 6, 2004
Driving up the inclined wall of the small crater the craft landed in, the Mars rover Opportunity was expected to arrive at the outer edge of bedrock outcropping early Saturday to begin its geologic work. Read our full story.
1820 GMT (1:20 p.m. EST)
A before-brushing image of the rock is here and this is the post-brushing view. A microscopic view of the brushed area is also available. Spirit will grind into the rock later today. Meanwhile, Opportunity completed another drive today. It didn't quite reach the rock outcrop, so a 30-40 centimeter drive is scheduled for tomorrow before science investigations can begin this weekend, mission manager Matt Wallace says.
THURSDAY, FEBRUARY 5, 2004
An image from the rover showing its tracks in the soil is available here. The rover made two arcs to the right, then one arc to the left, then a 30-degree turn in place, then a straight-ahead drive. Originally slated to dig a hole with one of its wheels Friday, officials scrapped that plan and decided to continue moving to the outcrop. The trenching will be rescheduled when the rover reaches an area where the soil has a higher concentration of large-grain hematite, NASA said. After waking up Thursday night/Friday morning (U.S. Time), the rover will drive about about five feet farther, possibly to within arm's reach of one of the rocks in the exposed outcrop, Mission Control reported. Meanwhile, the Spirit rover fresh off its flash file system reformatting conducted Wednesday was scheduled to brush the rock nicknamed Adirondack today before examination with its science instruments. The next rover news conference is scheduled for 1 p.m. EST Friday. We will update this page with more details at that time.
1605 GMT (11:05 a.m. EST)
On Opportunity, the rover was scheduled to make a 10-foot drive today to a spot where it will later spin one of its front wheels to dig a small hole in the soil for scientists to study.
WEDNESDAY, FEBRUARY 4, 2004
1920 GMT (2:20 p.m. EST)
The work was pushed back a couple of days while testing was completed on Earth. But a day of science planned for Monday was thwarted by a glitch on the rover. Mission manager Mark Adler provided this status briefing on Spirit during a news conference at about 1:20 p.m. EST: "On Sol 30 (Monday) we attempted to do some science operations, we had a day to wait for the testing to be completed on the format operation in the testbed. So we were going to continue our arm operations on Adirondack and take some microscopic images and spectra. Unfortunately, at the beginning of that day we tried to do a Sun find and that Sun find did not succeed -- it was not able to complete the Sun find operation. As a result, the subsequent activities were not allowed to continue because the vehicle wasn't certain of what its attitude was. "So we had to recover from that. We got a Sun find to work later in the day, but we did not succeed in the arm operations for that day. We believe the failure was related either to some activities that were ongoing on the spacecraft at that time that prevented an image to complete acquisition and analysis or there was a file used from the flash file system that was corrupted that may have also contributed to this. "So this may, in fact, be related to the flash file system issue. That further bolsters our desire to format the flash file system and get ourselves back into a clean state. "So Sol 31 (Tuesday) we did preparation for the format operation. We got the vehicle into a state where it was going to go sleep early, we were not going to do the overnight (communications) passes, to get the vehicle as cold as possible for this morning and to have as much power in the batteries because today the rover has a very, very long day. "Poor rover was woken up by its alarm clock this morning at 6 a.m., much earlier that it's been woken up before. We got the rover up and we rebooted into the cripple mode so it doesn't use the flash memory so we can do our operations on the flash memory. We are doing those operations now. "We are currently in a four-hour process, which started probably 20 minutes ago, that will go through and erase all the contents of the flash. That also provides us with a means of checking the flash hardware -- we are checking to make sure all of the flash hardware, all of the flash chips, are working because we are still not certain that there wasn't some hardware problem that contributed to what we found. We don't think there was but to be safe we want to make sure we check all of the flash memory to make sure it's good. So we are going through all 224 megabytes of the flash memory that is used for the file system and erasing it over the next couple of hours. "After that we will reboot the system and reformat that flash file system and get it back and operating. We should have the system back in normal operational mode later this afternoon. We expect then we will reintroduce our Odyssey (communications) pass overnight and tomorrow morning we will be able to go back to our science operations." Adler says engineers have cautiously approached the reformatting procedure to ensure no harm is caused. "That's why we've spent four days testing this in the testbed. It's not an operation that we do lightly. We did go through a lot of testing to make sure the operation does exactly what we expect. We've reconstructed the environment in the testbed that the vehicle is going to be operating in. We verified also that there are no other things, other side effects that the flash format/erase operation could have on the rest of the vehicle. "For example, we store our flight software images in another area of flash, separate from the flash file system. And we verified, in fact, that when we do this erase operation that there is no way those copies of flight software to be corrupted in any way. In fact, the sequence we've developed that's running today checks every step of the way that that doesn't happen and we'll abort if there is some issue that it sees and some side effects from the operation. "This is an operation you don't do just willy-nilly. You have to make sure it works right and we've done that (on Earth). So we're doing it on the spacecraft right now." If all goes well, Spirit will resume its study of Adirondack tomorrow by using the Rock Abrasion Tool to brush a portion of the rock's exterior and then allow its instruments to take images and measurements. On Friday, the Rock Abrasion Tool will actually grind into the rock, followed by further study with the instruments. Future plans call for Spirit to depart Adirondack this weekend and begin driving, bound for a large crater over 800 feet away. The next Mars news conference is scheduled for 1 p.m. EST Friday.
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NASA is currently holding a rover news conference. We'll post a full report this afternoon.
MONDAY, FEBRUARY 2, 2004
Meanwhile, NASA Administrator Sean O'Keefe today announced the Martian hills, located east of the Spirit Mars Exploration Rover's landing site, would be dedicated to the Space Shuttle Columbia STS-107 crew. Read the announcement. NASA is not planning a Mars status briefing on Tuesday. The next news conference is scheduled for 1 p.m. EST (1800 GMT) on Wednesday.
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Opportunity's arm extended can be seen here. A 3-D version is available here.
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Opportunity remains parked in the position it reached after driving off the lander Saturday. It will stay in that spot for several days while the soil investigations are completed. Then the rover will drive to the bedrock outcrop nearby. The arm, known as the Instrument Deployment Device, or IDD, carries the Mossbauer Spectrometer, Alpha Particle X-Ray Spectrometer, Microscopic Imager and Rock Abrasion Tool. Also during today's workday for Opportunity, the Rock Abrasion Tool was activated to ensure it was working. Next, the Microscopic Imager cover was successfully opened. Later, the arm maneuvered the Mossbauer and APXS instruments into view of the rover's cameras. The first science observations are being made with the Microscopic Imager, giving scientists unique views of the soil. Tomorrow, the German Mossbauer instrument will examine the soil to look for iron-bearing minerals. Meanwhile on Spirit, science operations are being performed today. The reformatting of the flash memory has been pushed back to tomorrow.
SUNDAY, FEBRUARY 1, 2004
"We have confirmed that Spirit is booting up normally. Tomorrow we'll be doing some preventive maintenance," mission manager Mark Adler said. Read our full story.
1930 GMT (2:30 p.m. EST)
SATURDAY, JANUARY 31, 2004
IMAGES OF SATURDAY'S ROVER DRIVE
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The Mars Exploration Rovers were sent to the Red Planet to look for proof of past water.
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Confirmation was received on Earth just after 6 a.m. EST via the Mars Odyssey relay. The rover is facing 32 degrees east of due north.
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"Two for two, one dozen wheels on soil," flight director Chris Lewicki says as Opportunity joins Spirit on the surface of Mars. A post-egress news conference is coming up at 6:45 a.m. EST.
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The rover will remain in its current position a few feet away from the lander for a couple of days, allowing its science arm to examine a patch of soil with the microscopic images and spectrometers. Opportunity will then drive to the bedrock outcrop along the crater wall about 25 feet northwest of the lander. Opportunity is near the center of a crater 72 feet in diameter and 10 feet deep. On Friday, scientists unveiled a three-dimensional model of the crater, created from information in stereo images. This is the first time a crater on another planet has been mapped from inside the crater. See the model here.
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"Twenty-nine minutes and counting," flight director Chris Lewicki tells his controllers.
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"Because of light time, the vehicle should already be on the surface at this time," flight director Chris Lewicki reported. It takes about 11 minutes for a signal to travel between Mars and Earth. "But I want to know now," another controller could be heard saying. Confirmation of a successful drive will be relayed through the Mars Odyssey orbiter around 6:15 a.m. EST.
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The honor of pushing the button to transmit the command from Earth to Opportunity was bestowed upon Kevin Burke, the lead mechanical engineer for the drive-off. With the mouse click complete, applause broke out in the control room.
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Shortly, commands will be issued to Opportunity to make the roll off the lander.
0802 GMT (3:02 a.m. EST)
Controllers are examining data in preparation to giving approval for Opportunity's drive off the lander later this morning.
FRIDAY, JANUARY 30, 2004
The massive batch of no-longer-needed files piled up on the rover and prevented its computer system from successfully accessing the flash memory. The flash memory stores engineering and scientific data. With the files gone, Spirit was rebooted late Friday. "I am pleased to report it appears to be working just fine," Glenn Reeves, chief engineer for the rover's flight software, was quoted as saying. NASA officials indicated it would be another day or two before they will know for sure that Spirit is entirely healthy again. As Spirit returns to action, the craft's Rock Abrasion Tool will be used in the next few days to reveal the interior of a rock dubbed Adirondack. The pyramid-shaped, football-sized rock is the first that Spirit drove to after leaving its lander base January 15. Meanwhile, Opportunity remains set to join its sister-rover on the Martian surface early Saturday when it rolls off its lander base on the opposite side of Mars.
1805 GMT (1:05 p.m. EST)
On the Martian workday Thursday, controllers checked out the rover's science instruments while continuing to investigate the computer problems. "We read out data from the Mossbauer Spectrometer and APXS (Alpha Particle X-ray Spectrometer) instruments. We also took several Pancam images with the panoramic imager up on the mast," Adler reported. The new Pancam views can be seen here. The photo shows the calibration target, the sun and two rocks that Spirit will be investigating later. "We also yesterday completed a scan of the flash memory. This provided us with some important diagnostic information. We are now able to tell that when we mount the flash memory, it does in fact take a lot of the system RAM in the process. In fact, more system RAM than is available. So that's helping confirm the theory we had that the reason the restarts were hanging up was because we were running out of memory when we are trying to mount the flash memory. "We still don't know if the number of files is the cause of that or what other characteristics of the contents of the flash file system are causing this. But that is what we are going to try and find out today. "Today on Sol 27 we are going to continue with the task trace that is going on right now -- about 10 a.m. on Sol 27," Adler told reporters at the 12 noon EST briefing. "We are going to take some pieces of memory after the rover is run up in the mode where it's not working properly and see if that shows trace information about what routines are running when the system hung up and not able to complete the reset. "After that, we are going to bring the system back up in what we call the cripple mode where we are able to have normal operations in the mode in which we are able to take pictures and you are able to use the instruments. And in that mode we are going to delete from the flash memory -- the flash file system -- a large number of files that were left over from the cruise phase of the mission before landing," Adler said. Engineers think that by deleting that batch of files, the rover might not require as much memory when trying to use the file management system. "After that we are going to try and reboot in the normal mode, the non-cripple mode, and see if the system comes up. We are hopeful that it will come up. At that point, we'll resume normal operations and begin to do some housekeeping on the system (and) begin to playback some data in the flash in preparation for possibly a flash file formatting on tomorrow on Sol 28." Spirit could resume full, normal operations on Sunday, a week-and-a-half after being sidelined by the computer trouble. If the file deletion doesn't fix the problem, controllers will get the rover back into the cripple mode and form a new plan of attack for tomorrow.
1740 GMT (12:40 p.m. EST)
THURSDAY, JANUARY 29, 2004
1740 GMT (12:40 p.m. EST)
On Wednesday, the screw jack mechanism elevated Opportunity's body so its two front wheels could unfold. The rocker-bogie suspension system was then locked into place. With the rover supporting its own weight, the lifting mechanism was retracted back into the lander this morning. Tonight, the middle two wheels will be released from their stowed position and the science arm will be unlatched from its launch location. Also on the just-completed Martian workday, Opportunity used the Mini-Thermal Emission Spectrometer instrument to observe a portion of the landing site terrain, including the rock outcrop. However, the data was not returned to Earth before the rover went to sleep for the night. Meanwhile, controllers today will perform health checks on Spirit's camera mast as they prepare that rover for returning to science operations next week. Last night, the rover sent back its first image since developing computer troubles a week ago. There is no Mars rover status news conference today. The next briefing is scheduled for Friday at 12 noon EST (1700 GMT).
WEDNESDAY, JANUARY 28, 2004
2110 GMT (4:10 p.m. EST)
1755 GMT (12:55 p.m. EST)
New close-up views of the rock formations at landing site are available here and here. Also, click here to see views of the marks that the lander's airbags made in the soil. You can compare the airbag markings with this ground testing image.
1734 GMT (12:34 p.m. EST)
The Sol 5 workday that begins late tonight (U.S. time) will see the lift mechanism retracted out of the rover's way and the deployment of the rear wheels. If all continues to go well, Opportunity could drive off the lander as early as Sunday night.
1730 GMT (12:30 p.m. EST)
1700 GMT (12:00 p.m. EST)
We'll update this page once the briefing begins -- as officials report on the scheduled efforts to deploy Opportunity's front wheels and the release of stunning new color imagery of the rock outcrop at the landing site.
TUESDAY, JANUARY 27, 2004
NASA memorialized the Apollo 1 crew - Gus Grissom, Ed White and Roger Chaffee - by dedicating the hills surrounding the Mars Exploration Rover Spirit's landing site to the astronauts. The crew of Apollo 1 perished in flash fire during a launch pad test of their Apollo spacecraft 37 years ago today. Read the announcement.
1820 GMT (1:20 p.m. EST)
"There is one new issue with the vehicle. We have discovered that there is a power loss that's going on in the vehicle. We think we know what's going on there. "There is a set of thermostatic-controlled heaters. One of them is located physically in the shoulder joint of the instrument arm. Normally this is enabled by the ground and then a thermostat on the side of the rover determines what the air temperature is and, if it's cold enough, it turns on this heater in this arm to keep it up in temperature for operation. "Normally we don't always want it on because we aren't normally always operating the arm. Right now, we are believing it is going to be on continuously whenever it's cold enough. "We have multiple investigation paths underway on this -- one making sure that our current theory of what this current draw is is correct, and others to begin to explore the issues of are there operational workarounds to keep this under control or possible solutions to be able to turn it off when we want it to be off." In response to questions after his briefing, Erickson also had this to add: "Right now we are seeing about a 15-watt resistance that's being dissipated somewhere. We have evidence this is where it's going to. At this point, I would like to have a little more time to look at what we are seeing from the vehicle before we make any judgments on exactly what's there." Erickson said it's too soon know what impact this issue might have. "It's not on continuously, let me make sure that is clear. It is only when the thermostat brings it on during the cold period of the day. We use it to keep the rover's shoulder mechanism warm enough to operate correctly. Apparently it is going to be warm enough to operate correctly whether we want it to be operated or not! "We are very paranoid people. So now that we're thinking about having this on all of the time, if that's really the problem, we have already asked people to start thinking about 'well, is this something long-term that might be an issue?' We just have to have time to have those people go back, do their analysis and come let us know. We always assume there is a problem until we prove otherwise."
1745 GMT (12:45 p.m. EST)
A three-dimensional version, for those of you with 3-D glasses, can be seen here. Also, a computer animation image has been created showing the rover at the outcrop.
1730 GMT (12:30 p.m. EST)
Also, the second of the three umbilical cable bundles running from the lander to rover has been cut. On the workday that begins tonight, Sol 4, a lift mechanism on the lander base will raise up the rover, allowing the front wheels to be unfolded from their stowed launch position and locked into place. These are just the first steps to get the rover configured to drive off the lander late next week. Controllers are looking at an issue on Opportunity. Telemetry from the rover indicates a small power draw, which engineers suspect is a heater on the science arm's shoulder joint that is operating during the cold period of the each day instead of simply when the arm is being used. Mission manager Jim Erickson says it is too soon to say what, if any, impact this will have. Overall, he says Opportunity is in "pretty good shape." Meanwhile, the science team is giddy from new imagery taken by Opportunity showing finely-layered rocks in the light-colored, tabular-shaped outcrop formations near the rover landing site. It isn't yet known if the layering was caused by water or volcanic activity. Opportunity will drive to the rock outcrop after leaving the lander to begin extensive examination with its suite of science instruments.
MONDAY, JANUARY 26, 2004
1830 GMT (1:30 p.m. EST)
Scientists say this is the darkest landing site ever visited by a Mars spacecraft. The rim of the crater is approximately 32 feet from the rover. The crater is estimated to be 65 feet in diameter. There are rock outcrops dispersed throughout the crater. The soil appears to be a mixture of coarse gray grains and fine reddish grains. Data taken from the camera's near-infrared, green and blue filters were combined to create this approximate true color picture. The view is to the west-southwest of the rover.
1730 GMT (12:30 p.m. EST)
Mission manager Jim Erickson says controllers are making "steady progress" to prepare Opportunity for eventually driving off the lander. The roll is expected late next week.
1701 GMT (12:01 p.m. EST)
The devices are located on the rover's science arm, and will be used for close-up examination of soil and rocks at Meridiani.
0500 GMT (12:00 a.m. EST)
0400 GMT (11:00 p.m. EST Sun.)
The batch of science-related commands for the rover include health checks of the Alpha Particle X-Ray Spectrometer and Mossbauer Spectrometer, a test image of the Microscopic Imager and snapping photos of the landing site using the panoramic camera.
0318 GMT (10:18 p.m. EST Sun.)
0301 GMT (10:01 p.m. EST Sun.)
0249 GMT (9:49 p.m. EST Sun.)
"X-band system is working on the surface of Mars," flight director Chris Lewicki reported as communications were successfully established. This is a planned 45-minute communications session between the rover and Earth in which health data will be received and controllers will verify earlier sequence commands transmitted did arrive onboard Opportunity. Earlier communications sessions were performed using the Mars Global Surveyor and Mars Odyssey orbiting around the planet. The craft received data from the rover and relayed the information to Earth.
SUNDAY, JANUARY 25, 2004
2116 GMT (4:16 p.m. EST)
As suspected overnight when the first images arrived on Earth, the rover has landed inside "a 20-meter diameter" crater, Squyres reports. The crater is estimated to be "a couple of meters deep." Therefore, it should not be a challenge for the rover to drive out, he said. A much larger crater, seen in the descent camera images, is near the lander and likely within reach of Opportunity to explore.
2106 GMT (4:06 p.m. EST)
In the past day, engineers have determined that Spirit's flash memory hardware is OK. A leading theory today is that a portion of the rover's software simply couldn't cope with all that was happening on Wednesday when the trouble began. The rover's batteries are now fully charged and the craft shortly will be going to sleep for the night. But before nighttime it will be relaying data to the Mars Odyssey orbiter including engineering and diagnostic information. Theisinger predicts that Spirit will resume driving around the surface in a couple of weeks. Meanwhile, the Opportunity rover is operating properly following its landing last night.
2050 GMT (3:50 p.m. EST)
2034 GMT (3:34 p.m. EST)
A NASA news conference is upcoming at 4 p.m. EST.
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Mission Control says the data bundle should include the pictures from the lander's descent imaging camera showing the surface just prior to touchdown.
1215 GMT (7:15 a.m. EST)
We will update this page when information becomes available from the Odyssey pass. The next rover news conference is scheduled for 4 p.m. EST.
1140 GMT (6:40 a.m. EST)
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1020 GMT (5:20 a.m. EST)
"This is exactly what it looked like in my wildest dreams. But they were pretty wild!" Squyres says. Squyres guesses the rover might actually be down in a crater.
1009 GMT (5:09 a.m. EST)
1007 GMT (5:07 a.m. EST)
The heading is about 26 degrees or north-northeast.
1002 GMT (5:02 a.m. EST)
"I am just speechless," said JPL director Charles Elachi. "A friend of mine told me 'good things happen slowly but great things happen suddenly.' Today, I know exactly what he meant."
0950 GMT (4:50 a.m. EST)
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As the images were coming to Earth, rover scientist Steve Squyres said, "I will attempt no science analysis because it looks like nothing I've ever seen before in my life."
0927 GMT (4:27 a.m. EST)
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0923 GMT (4:23 a.m. EST)
"I've got no words for this!" he says.
0918 GMT (4:18 a.m. EST)
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"You are privileged to be in one of the most exciting rooms on Earth at the moment," says flight director Chris Lewicki. If all goes well, this data to be received will begin with engineering health information about the rover and be followed by images from various cameras on Opportunity.
0859 GMT (3:59 a.m. EST)
0857 GMT (3:57 a.m. EST)
"Cheer!" flight director Chris Lewicki jokingly instructed his team. The fact that telemetry has been received indicates that the rover has performed its critical deployment activities following landing. Opportunity's exact status has yet to be confirmed, however. That is still to come.
0856 GMT (3:56 a.m. EST)
0845 GMT (3:45 a.m. EST)
"Earthset" has occurred -- meaning that Earth is no longer visible from landing site for tonight.
0745 GMT (2:45 a.m. EST)
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0717 GMT (2:17 a.m. EST)
The Mars Odyssey orbiter will fly over the landing site in about 90 minutes to relay data back to Earth.
0714 GMT (2:14 a.m. EST)
0706 GMT (2:06 a.m. EST)
0700 GMT (2:00 a.m. EST)
0657 GMT (1:57 a.m. EST)
The U.S. now has logged five successful landings on Mars out of six attempts -- Opportunity, Spirit, Pathfinder and two Vikings. The only failure was Mars Polar Lander.
0649 GMT (1:49 a.m. EST)
"What a night! I mean, as the old saying goes 'it's far better to be lucky than good.' But you know the harder we work, the luckier we seem to get," O'Keefe said. "This team is absolutely phenomenal. The very idea that no one dared dream that we could pull off batting a thousand on this. Yet this is a tremendous testimonial of how NASA can really focus on the objective and put every ounce of effort, energy, emotion and talent to an important task. This is just a truly remarkable achievement. This team is the best in the world, no doubt about it!"
0637 GMT (1:37 a.m. EST)
Both Mars Exploration Rovers -- Spirit and Opportunity -- have safely reached the Red Planet just three weeks apart. The two rovers are located half a world away from each other, having traveled 300 million miles from Earth to Mars. Although Spirit developed a problem more than two weeks into its mission, engineers remain hopeful it can resume exploring Gusev Crater. The Opportunity post-landing news conference will begin shortly.
0545 GMT (12:45 a.m. EST)
0535 GMT (12:35 a.m. EST)
Also, they believe that Opportunity wasn't really rolling all of that time. The fluctuating indication interpreted as rolling was actually an artifact of the communications path with the craft on its side and not the vehicle still in motion.
0532 GMT (12:32 a.m. EST)
0528 GMT (12:28 a.m. EST)
Next, the rover will deploy its power-generating solar panels. Then the Pancam Mast Assembly will be raised up. It can begin taking some pictures of the landing site once those events are completed. The initial images, if snapped this morning, would be relayed to Earth via the Mars Odyssey orbiter overnight.
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Here is an overview: The system for getting each rover safely through Mars' atmosphere and onto the surface relies on an aeroshell, a parachute and airbags. The aeroshell has two parts: a heat shield that faces forward and a backshell. Both are based on designs used successfully by NASA's Viking Mars landers in 1976 and Mars Pathfinder in 1997. The parachute is attached to the backshell and opens to about 15 meters (49 feet) in diameter. The parachute design was tested under simulated martian conditions in a large wind tunnel at NASA's Ames Research Center near Sunnyvale, Calif. The backshell carries a deceleration meter used to determine the right moment for deploying the parachute. Solid-fuel rockets mounted on the underside of the shell reduce vertical velocity and any excessive horizontal velocity just before landing. The airbags, based on Pathfinder's design, cushion the impact of the lander on the surface. Each of the four faces of the folded-up lander is equipped with an envelope of six airbags stitched together. Explosive gas generators rapidly inflate the airbags to a pressure of about 6900 Pascal (one pound per square inch). Each airbag has double bladders to support impact pressure and, to protect the bladders from sharp rocks, six layers of a special cloth woven from polymer fiber that is five times stronger than steel. The fiber material, Vectran, is used in the strings of archery bows and tennis racquets.
0451 GMT (11:51 p.m. EST Sat.)
0449 GMT (11:49 p.m. EST Sat.)
The system has about 100 possible tones to provide information such as whether the cruise stage has separated, whether the parachute opens and whether the deceleration rate is within the expected range.
0448 GMT (11:48 p.m. EST Sat.)
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0445 GMT (11:45 p.m. EST Sat.)
Opportunity is poised for entering the atmosphere in about 13 minutes.
0444 GMT (11:44 p.m. EST Sat.)
0443 GMT (11:43 p.m. EST Sat.)
0441 GMT (11:41 p.m. EST Sat.)
0440 GMT (11:40 p.m. EST Sat.)
Opportunity is currently 2,183 miles from Mars, traveling over 9,400 miles per hour.
0435 GMT (11:35 p.m. EST Sat.)
The next major event will be separation between the no-longer-needed cruise stage from the descent module containing the Opportunity rover. This jettison is scheduled for 11:44 p.m. EST. Here is NASA's description of the cruise stage: The cruise stage provides capabilities needed during the seven-month passage to Mars but not later in the mission, such as a propulsion system for trajectory correction maneuvers. Approximately 2.6 meters (8.5 feet) in diameter and 1.6 meters (5.2 feet) tall, the disc-shaped cruise stage is outfitted with solar panels and antennas on one face, and with fuel tanks and the aeroshell on the other. Around the rim sit thrusters, a star scanner and a Sun sensor. The propulsion system uses hydrazine propellant stored in two titanium tanks. Since the the entire spacecraft spins at about 2 rotations per minute, fuel in the tanks is pushed outward toward outlets and through fuel lines to two clusters of thrusters. Each cluster has four thrusters pointing in different directions. The star scanner and Sun sensor help the spacecraft determine its orientation. Since the rover's solar arrays are tucked away inside the aeroshell for the trip, the cruise stage needs its own for electrical energy. The arrays could generate more than 600 watts when the spacecraft was about as far from the Sun as Earth is, and generate about half that much as it nears Mars. The cruise stage also carries a system for carrying excess heat away from the rover's computer with a pumped freon loop and rim-mounted radiators.
0431 GMT (11:31 p.m. EST Sat.)
Mission Control confirms that the gas generator heaters are active.
0426 GMT (11:26 p.m. EST Sat.)
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0420 GMT (11:20 p.m. EST Sat.)
This venting will cause the spacecraft to wobble a bit, so tiny thrusters will be used to keep the lander on course for entry.
0418 GMT (11:18 p.m. EST Sat.)
Jettison of the cruise stage is upcoming at 11:44 p.m. and entry into the atmosphere begins at 11:59 p.m.
0415 GMT (11:15 p.m. EST Sat.)
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0412 GMT (11:12 p.m. EST Sat.)
This turn was a critical event prior to Opportunity maki |
