Spirit rover

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Objectives

• Search for and characterize a variety of rocks and soils that hold clues to past water
  Water
  
  Water is a common chemical substance that is essential for the survival of all known forms of life. In typical usage, water refers only to its liquid form or States of matter, but the substance also has a solid state, ice, and a gaseous state, water vapor or steam....
   activity. In particular, samples sought will include those that have minerals deposited by water-related processes such as precipitation
  Precipitation (meteorology)
  
  File:MeanMonthlyP.gifIn meteorology, precipitation is any product of the condensation of Atmosphere water vapor that is deposited on the earth's surface....
  , evaporation
  Water vapor
  
  Water vapor or water vapour , also aqueous vapor, is the gas phase of water . Water vapor is one Phase of the water cycle within the hydrosphere....
  , sedimentary cementation
  Sedimentary rock
  
  Sedimentary rock is one of the three main Rock types . Sedimentary rock is formed by deposition and consolidation of mineral and organic material and from precipitation of minerals from solution....
   or hydrothermal activity.
• Determine the distribution and composition of minerals, rocks, and soils surrounding the landing sites.
• Determine what geologic processes
  Geology of Mars
  
  The geology of Mars, also known as areology , refers to the study of the composition, structure, physical properties, history, and the processes that shape the planet Mars....
   have shaped the local terrain and influenced the chemistry. Such processes could include water or wind erosion, sedimentation, hydrothermal mechanisms, volcanism, and cratering.
• Perform calibration and validation of surface observations made by Mars Reconnaissance Orbiter
  Mars Reconnaissance Orbiter
  
  NASA's Mars Reconnaissance Orbiter is a multipurpose spacecraft designed to conduct reconnaissance and exploration of Mars from orbit.When MRO entered orbit there were five other spacecraft in orbit of or on Mars: Mars Global Surveyor, Mars Express Orbiter, Mars Odyssey, and two Mars Exploration Rovers; a then record for mo...
   instruments. This will help determine the accuracy and effectiveness of various instruments that survey Martian geology
  Geology of Mars
  
  The geology of Mars, also known as areology , refers to the study of the composition, structure, physical properties, history, and the processes that shape the planet Mars....
   from orbit.
• Search for iron
  Iron
  
  Iron is a chemical element with the symbol Fe and atomic number 26. Iron is a Group 8 element and period 4 element. Iron is lustrous and silvery in color....
  -containing minerals, identify and quantify relative amounts of specific mineral types that contain water or were formed in water, such as iron-bearing carbonates.
• Characterize the mineralogy
  Mineralogy
  
  Mineralogy is an Earth Science focused around the chemistry, crystal structure, and physical properties of minerals. Specific studies within mineralogy include the processes of mineral origin and formation, classification of minerals, their geographical distribution, as well as their utilization....
   and textures of rocks and soils and determine the processes that created them.
• Search for geological clues to the environmental conditions
  Environmental science
  
  Environmental science is an expression encompassing the wide range of scientific disciplines that need to be brought together to understand and manage the natural environment and the many interactions among physics, chemistry, and biology components....
   that existed when liquid water was present.
• Assess whether those environments were conducive to life
  Life
  
  Life is a characteristic of organisms that exhibit certain biological processes such as chemical reactions or other events that results in a transformation....
  .

Science instruments carried

Landing site: Columbia Memorial Station

Events and discoveries

Timeline

Sleepy Hollow

First color photograph

January 21 flash memory management anomaly

") to try to cause it to suspend itself until a given time. It seemingly ignored the command.

The leading theory at the time was that the rover was stuck in a "reboot loop". The rover is programmed to reboot if there's a fault aboard itself. However, if there is a fault that occurs during reboot, it could continue to reboot forever. The fact that the problem persisted through reboot suggested that the error was not in RAM, but in either the flash memory

Flash memory

Flash memory is a non-volatile memory computer storage that can be electrically erased and reprogrammed. It is a technology that is primarily used in memory cards and USB flash drives for general storage and transfer of data between computers and other digital products....
, the EEPROM

EEPROM

EEPROM stands for Electrically Erasable Programmable Read-Only Memory and is a type of non-volatile memory used in computers and other electronic devices to store small amounts of data that must be saved when power is removed, e.g., calibration tables or device configuration....
, or a hardware fault. The last case would likely mean the doom of the rover. Anticipating the potential for errors in the flash memory and EEPROM, the designers had made it so that the rover could be booted without ever touching the flash memory. The radio itself could decode a limited commandset — enough to tell the rover to reboot without using flash. Without access to flash memory, Spirit booted fine, and the reboot cycle was broken.

On January 24 the rover repair team announced that the problem was with Spirits flash memory and the software that wrote to it. The flash hardware was believed to be working correctly but the file management module in the software was "not robust enough" for the operations the Spirit was engaged in when the problem occurred, indicating that the problem was caused by a software bug as opposed to faulty hardware. NASA engineers finally came to the conclusion that there were too many files on the file system, which was a relatively minor problem. Most of these files contained unneeded in-flight data. After realizing what the problem was, the engineers deleted some files, and eventually reformatted the entire flash memory system. On February 6 (Sol 33), the rover was restored to its original working condition, and science activities resumed.

History's first grinding of a rock on Mars

The round, shallow depression in this image resulted from history's first grinding of a rock on Mars. The Rock Abrasion Tool

Rock Abrasion Tool

The Rock Abrasion Tool is a grinding and brushing installation on NASA?s twin Mars Exploration Rovers, Spirit rover and Opportunity rover , which landed on Mars in January 2004....
 on NASA's Spirit rover ground off the surface of a patch 45.5 millimeters (1.8 inch

Inch

An inch is the name of a Units of measurement of length in a number of different systems, including Imperial units, and United States customary units....
es) in diameter on a rock called Adirondack

Adirondack (Mars)

Adirondack is the nickname for Mars Exploration Rover Mission MER-A'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....
 during Spirit's 34th sol on Mars, February 6, 2004. The hole is 2.65 millimeters (0.1 inch) deep, exposing fresh interior material of the rock for close inspection with the rover's microscopic imager and two spectrometers on the robotic arm. This image was taken by Spirit's panoramic camera, providing a quick visual check of the success of the grinding.

"The RAT

Rock Abrasion Tool

The Rock Abrasion Tool is a grinding and brushing installation on NASA?s twin Mars Exploration Rovers, Spirit rover and Opportunity rover , which landed on Mars in January 2004....
 performed beyond our expectations," beamed Steve Gorevan, of Honeybee Robotics, New York, lead scientist for the rock abrasion tools on both rovers. "With the docile cutting parameters we set, I didn't think that it would cut this deep. In fact, when we saw virtually a complete circle, I was thrilled beyond anything I could have ever dreamed. Following up that glorious circular brushing — it's like back-to-back homers."

Mimi

This color image taken by the Mars Exploration Rover Spirits panoramic camera on Sol 40 is centered on an unusually flaky rock called Mimi. Mimi is only one of many features in the area known as "Stone Council", but looks very different from any rock that scientists have seen at the Gusev crater site so far. Mimi's flaky appearance leads scientists to a number of hypotheses. Mimi could have been subjected to pressure either through burial or impact, or may have once been a dune that was cemented into flaky layers, a process that sometimes involves the action of water.

Humphrey and clues for water

On March 5, 2004, NASA announced that Spirit had found hints of water history on Mars in a rock dubbed "Humphrey". Dr. Raymond Arvidson, Ph.D., the McDonnell University Professor and chair of Earth and planetary sciences at Washington University in St. Louis

Washington University in St. Louis

Washington University in St. Louis is a nonsectarian, private University located in Greater St. Louis. Founded in 1853 and named for George Washington, the university has students and faculty from all fifty U.S....
, reported during a NASA press conference: "If we found this rock on Earth, we would say it is a volcanic rock that had a little fluid moving through it." In contrast to the rocks found by the twin rover Opportunity, this one was formed from magma

Magma

Magma is molten Rock that is found beneath the surface of the Earth, and may also exist on other terrestrial planets. Besides molten rock, magma may also contain suspended crystals and gas bubbles....
 and then acquired bright material in small crevices, which look like crystallized minerals. If this interpretation holds true, the minerals were most likely dissolved in water, which was either carried inside the rock or interacted with it at a later stage, after it formed.

Bonneville Crater

On 11 March 2004, the Spirit rover reached Bonneville crater

Bonneville (crater)

Bonneville is an impact crater on Mars . It is located within the much larger crater Gusev. Bonneville was visited by the Spirit rover in 2004, during its exploration of the floor of Gusev....
 after a journey. This crater is about across with a floor about below

Crater depth

The depth of any crater in a solid planet or Natural satellite - whether it is an impact crater, a volcanic crater, or a subsidence crater - may be measured from the local surface to the bottom of the crater, or from the rim of the crater to the bottom....
 the surface. JPL decided that it would be a bad idea to send the rover down into the crater, as they saw no targets of interest inside. Spirit drove along the southern rim and continued to the southwest towards the Columbia Hills.

Missoula and Lahontan Craters, en route to Columbia Hills

Spirit reached Missoula crater on Sol 105. The crater is roughly across and deep. Missoula crater was not considered a high priority target due to the older rocks it contained. The rover skirted the northern rim, and continued to the southeast. It then reached Lahontan crater on Sol 118, and drove along the rim until Sol 120. Lahontan is about across and about deep. A long, snaking sand dune stretches away from its southwestern side, and Spirit went around it, because loose sand dunes present an unknown risk to the ability of the rover wheels to get traction.

Columbia Hills

On Sol 159, Spirit reached the first of many targets at the base of the Columbia Hills called West Spur. Hank's Hollow was studied for 23 sols. Within Hank's Hollow was the strange looking rock dubbed "Pot of Gold

Pot of Gold (Mars)

Pot of Gold is the nickname for a knobby, softball-sized rock in Gusev Crater on Mars. During an examination by the Mars Exploration Rover Spirit rover on June 25, 2004 Hematite was first detected by Spirit, suggesting a watery past on Mars....
".

From here, Spirit took a northerly path along the base of the hill towards the target Wooly Patch, which was studied from Sol 192 to Sol 199. By Sol 203, Spirit had driven southward up the hill and arrived at the rock dubbed "Clovis". Clovis was ground and analyzed from Sol 210 to Sol 225. Following Clovis came the targets of Ebenezer (Sols 226-235), Tetl (Sol 270), Uchben and Palinque (Sols 281-295), and Lutefisk (Sols 296-303). From Sols 239 to 262, Spirit powered down for solar conjunction

Solar conjunction

Solar conjunction occurs when a planet or other solar system object is on the opposite side of the sun from the Earth. From an Earth reference, the object will pass behind the sun....
, when communications with the Earth are blocked.

Slowly, Spirit has made its way around the summit of Husband Hill, and at Sol 344 was ready to climb over the newly designated "Cumberland Ridge" and into "Larry's Lookout

Larry's Lookout

Larry's Lookout is located on Husband Hill, Gusev Crater, Mars. It is named after geologist Larry Crumpler.In 2005 MER-A, a Mars Exploration Rover, spent 70 Timekeeping on Marss ascending Larry's Lookout and then 4 sols taking panoramic photographs of the Tennessee Valley below....
" and "Tennessee Valley".

On Sol 371, Spirit arrived at a rock named "Peace" near the top of Cumberland Ridge. Spirit ground it with the RAT tool on Sol 373.

By Sol 390 (Mid-February 2005), Spirit was advancing towards "Larry's Lookout", by driving up the hill in reverse. The scientists at this time were trying to conserve as much energy as possible for the climb.

Spirit also investigated some targets along the way, including the soil target, "Paso Robles", which contained the highest amount of salt

Salt

A salt, in chemistry, is defined as the product formed from the neutralisation reaction of acids and base . Salts are ionic compounds composed of cations and anions so that the product is electrically electric charge ....
 found on the red planet. The soil also contained a high amount of phosphorus

Phosphorus

Phosphorus is the chemical element that has the symbol P and atomic number 15. The name comes from the and . A Valency nonmetal of the nitrogen group, phosphorus is commonly found in inorganic phosphate minerals....
 in its composition, however not nearly as high as another rock sampled by Spirit, "Wishstone". Squyres said of the discovery, "We're still trying to work out what this means, but clearly, with this much salt around, water had a hand here".

On 9 March 2005 (probably during the Martian night), the rover's solar panel efficiency jumped from around 60% of what it had originally been to 93%, followed on 10 March by the sighting of dust devils

Dust Devils

Dust Devils is an indie role-playing game role-playing game set in the Old West, written by Matt Snyder. It was voted the 2002 Indie RPG Game of the Year; it also won the Best Synergy of Game and Rules category, as well as placing in the Best Production and Most Innovative Game categories....
. NASA scientists speculate a dust devil must have swept the solar panels clean, possibly significantly extending the duration of the mission. This also marks the first time dust devils had been spotted by either Spirit or Opportunity, easily one of the top highlights of the mission to date. Dust devils had previously been photographed by only the Pathfinder probe.

Husband Hill summit

On Sol 582, August 21, 2005, Spirit reached the summit of Husband Hill

Husband Hill

Husband Hill is one of the Columbia Hills in Gusev crater, Mars. It was named in honor of Rick D. Husband, an astronaut and commander of the Space Shuttle Columbia during its final mission, during which it disintegrated upon reentry ....
 and acquired a 360 degree panorama picture.

Home Plate

Spirit arrived at the north west corner of Home Plate

Home Plate (Mars)

Home Plate is a plateau roughly 90 m across within the Columbia Hills, Mars. It is informally named after a baseball home plate due to the similarity in shape....
, a raised and layered outcrop on sol 744 after an effort to maximize driving. Scientific observations have been conducted with Spirit's robotic arm.

During 2007 Spirit spent several months near the base of the Home Plate plateau. On sol 1306 Spirit climbed onto the eastern edge of the plateau. In September and October it examined rocks and soils at several locations on the southern half of the plateau. On November 6 Spirit had reached the western edge of Home Plate and starting taking pictures for a panoramic overview of the western valley with Grissom Hill and Husband Hill visible. The panorama image was published on NASA's website on January 3, 2008 to little attention, until January 23, when an independent website published a magnified detail of the left side of the original image in which is visible what looks much like a dark green humanoid sitting on a rock or walking down a hill with the right arm raised. This strange formation is also visible when viewing the image in full resolution on the NASA website. The presence of the feature in all separate images which were combined to make the color image as well as NavCam images from several days earlier, conclusively show that it is a permanent feature.

McCool Hill

Spirit's next stop was originally planned to be the north face of McCool Hill

McCool Hill

McCool Hill is the tallest of the Columbia Hills in Gusev , Mars. It was named in honor of William C. McCool, an astronaut of the Space Shuttle Columbia during its final mission where it disintegrated during reentry ....
, where Spirit would receive adequate sunlight during the Martian winter. On March 16, 2006 JPL announced that Spirit's troublesome front wheel had stopped working altogether. Despite this, Spirit was still making progress toward McCool Hill because the control team programmed the rover to drive toward McCool Hill backwards, dragging its broken wheel. In late March, Spirit encountered loose soil which was impeding its progress toward McCool Hill. A decision was made to terminate attempts to reach McCool Hill and instead park on a nearby ridge named Low Ridge Haven.

Low Ridge Haven

Reaching the ridge on April 9, 2006 and parking on the ridge with an 11° incline to the north, Spirit spent the next eight months on the ridge during which time undertaking observations of changes in the surrounding area. No drives were attempted because of the low power levels the rover was experiencing during the Martian winter. The rover made its first drive, a short turn to position targets of interest within reach of the robotic arm, in early November 2006, following the shortest days of winter and solar conjunction when communications with Earth were severely limited.

While at Low Ridge, Spirit imaged two rocks of similar chemical nature to that of Opportunitys Heat Shield Rock

Heat Shield Rock

Heat Shield Rock is a basketball-sized iron-nickel meteorite found on Mars by the Mars rover Opportunity rover in January 2005. The meteorite was formally named Meridiani Planum by the Meteoritical Society in October, 2005 ....
, a meteorite

Meteorite

A meteorite is a natural object originating in outer space that survives an impact with the Earth's surface. While in space it is called a meteoroid....
 on the surface of Mars. Named "Zhong Shan" for Sun Yat-sen

Sun Yat-sen

Sun Yat-sen , also known as Sun Yixian, Sun Wen, Sun Itchisen/Sun Itchiyama and Sun Zhongshan , was a China revolutionary and Politician leader often referred to as the Father of the Nation....
 and "Allan Hills" for the location

Allan Hills

Allan Hills is a site in Victoria Land, in the Eastern region of Antarctica, at the end of the Transantarctic Mountains range. Numerous meteorites have been discovered here, including the meteorite ALH84001 originating from Mars, which has been claimed to contain evidence of Martian life in the form of micro-organisms....
 in Antarctica

Antarctica

Antarctica is Earth's southernmost continent, overlying the South Pole. It is situated in the Antarctica of the southern hemisphere, almost entirely south of the Antarctic Circle, and is surrounded by the Southern Ocean....
 where several Martian meteorites have been found, they stood out against the background rocks which were darker. Further spectrographic testing is being done to determine the exact composition of these rocks, which may turn out to also be meteorites.

Dust storms

Towards the end of June, 2007, a series of dust storms began clouding the Martian atmosphere with dust. The storms intensified and by July 20, both Spirit and Opportunity were facing the real possibility of system failure due to lack of power. NASA released a statement to the press which said (in part) "We're rooting for our rovers to survive these storms, but they were never designed for conditions this intense" . The key problem caused by the dust storms is a dramatic reduction in solar power. There was so much dust in the atmosphere that it was blocking 99 percent of direct sunlight to the rover Opportunity, whereas Spirit was getting slightly more sunlight.

Normally the solar arrays are able to generate up to 700 watt hours of power a day. After the storms, the amount of power generated was greatly reduced to 128 watts. If the rovers generate less than 150 watt hours per day they have to start draining their batteries to run survival heaters. If the batteries run dry, key electrical elements are likely to fail due to the intense cold. Both landers were put into the lowest-power setting to wait out the storms. In early August the storms began to clear slightly and the rovers successfully charged their batteries. They were kept in hibernation to wait out the rest of the storm.

On November 10, 2008, a large dust storm further reduced the output of the solar panels to 89 watt hours per day -- a critically low level not seen heretofore. NASA officials were hopeful that Spirit would survive the storm and the power level would rise once the storm had passed and the skies started clearing. They have attempted to conserve power and keep manual control of the rover. On Thursday November 13, 2008 the rover awoke and communicated back again.

From November 14, 2008 to November 20, 2008 Spirit averaged 169 watt hours per day and the heaters for the thermal emission spectrometer, which uses about 27 watt hours per day, have been disabled since November 11, 2008. Tests on the thermal emission spectrometer indicate that it is undamaged and the heaters for it will be enabled when there is sufficient power. The skies over Spirit are expected to clear over the next few weeks. The solar conjunction

Solar conjunction

Solar conjunction occurs when a planet or other solar system object is on the opposite side of the sun from the Earth. From an Earth reference, the object will pass behind the sun....
, where the Sun is between Earth and Mars, started on November 29, 2008 and communication with the rovers was not possible until December 13, 2008.

On February 6, 2009, a beneficial wind blew off the some of the dust accumulated on the panels. This has led to an increase in power output to 240 watt hours per day. NASA officials have said that this increase in energy will be used predominantly for driving.

Microbe clue

Spirit's

Spirit rover

MER-A , known as Spirit, is the first of the two rover s of NASA's Mars Exploration Rover Mission. It landed successfully on Mars on 04:35 Ground UTC on January 4, 2004, three weeks before its twin Opportunity rover landed on the other side of the planet....
 dead wheel turned out to be a mixed blessing. As it was traveling, pulling the dead wheel behind, the wheel scraped off the upper layer of the martian soil, uncovering a patch of ground that scientists say shows evidence of a past environment that would have been perfect for microbial life. It is similar to areas on Earth where water or steam from hot springs came into contact with volcanic rocks. On Earth, these are locations that tend to teem with bacteria, said rover chief scientist Steve Squyres

Steve Squyres

Steven W. Squyres is the Goldwin Smith Professor of Astronomy at Cornell University in Ithaca, New York. His research area is in planetary sciences, with a focus on large solid bodies in the solar system such as the terrestrial planets and the moons of the Jovian planets....
. "We're really excited about this," he told a meeting of the American Geophysical Union (AGU). The area is extremely rich in silica

Silicon dioxide

The chemical compound 'silicon dioxide', also known as 'silica' , is an oxide of silicon with a chemical formula of and has been known for its hardness since antiquity....
 - the main ingredient of window glass. The researchers have now concluded that the bright material must have been produced in one of two ways. One: hot-spring deposits produced when water dissolved silica at one location and then carried it to another (i.e. a geyser). Two: acidic steam rising through cracks in rocks stripped them of their mineral components, leaving silica behind. "The important thing is that whether it is one hypothesis or the other, the implications for the former habitability of Mars are pretty much the same," Squyres explained to BBC News. Hot water provides an environment in which microbes can thrive and the precipitation of that silica entombs and preserves them. Squyres added, "You can go to hot spring

Hot spring

A hot spring is a Spring that is produced by the emergence of Geothermal groundwater from the earth's crust . There are hot springs all over the earth, on every continent and even under the oceans and seas....
s and you can go to fumarole

Fumarole

A fumarole is an opening in Earth's Crust , often in the neighborhood of volcanoes, which emits steam and gases such as carbon dioxide, sulfur dioxide, hydrochloric acid, and hydrogen sulfide....
s and at either place on Earth it is teeming with life - microbial life

Microorganism

A microorganism or microbe is an organism that is microscopic . The study of microorganisms is called microbiology, a subject that began with Anton van Leeuwenhoek's discovery of microorganisms in 1675, using a microscope of his own design....
.

Astronomy

Spirit pointed its cameras towards the sky and observed a transit

Astronomical transit

File:Moon transit of sun large.oggThe term transit or astronomical transit has three meanings in astronomy:* A transit is the astronomy event that occurs when one celestial body appears to move across the face of another celestial body, as seen by an observer at some particular vantage point....
 of the Sun

Sun

The Sun , a G V star, is the star at the center of the Solar System. The Earth and other matter orbit the Sun, which by itself accounts for about 98.6% of the Solar System's mass....
 by Mars' moon

Natural satellite

A natural satellite or moon is a celestial body that orbits a planet or smaller body, which is called the primary. Technically, the term natural satellite could refer to a planet orbiting a star, or a dwarf galaxy orbiting a major galaxy, but it is normally synonymous with moon and used to identify non-artificial satellites...
 Deimos

Deimos (moon)

Deimos , is the smaller and outer of Mars? two natural satellite . It is named after Deimos , a figure representing dread in Greek Mythology. Its Astronomical_naming_conventions#Natural_satellites_of_planets is ....
 (see Transit of Deimos from Mars

Transit of Deimos from Mars

A transit of Deimos across the Sun as seen from Mars takes place when Deimos passes directly between the Sun and a point on the surface of Mars, obscuring a small part of the Sun's disc for an observer on Mars....
). It also took the only photo of Earth from the surface of another planet in early March 2004.

In late 2005, Spirit took advantage of a favorable energy situation to make multiple nighttime observations of both of Mars' moons Phobos

Phobos (moon)

'Phobos' is the larger and closer of Mars ' two small natural satellites, the other being Deimos . It is named after the Greek mythology Phobos , a son of Ares ....
 and Deimos

Deimos (moon)

Deimos , is the smaller and outer of Mars? two natural satellite . It is named after Deimos , a figure representing dread in Greek Mythology. Its Astronomical_naming_conventions#Natural_satellites_of_planets is ....
. These observations included a "lunar

Lunar eclipse

A lunar eclipse occurs whenever the Moon passes through some portion of the Earth's shadow. This can occur only when the Sun, Earth, and Moon are aligned exactly, or very closely so, with the Earth in the middle....
" (or rather phobal) eclipse

Eclipse

An eclipse is an astronomical event that occurs when one celestial object moves into the shadow of another. The term is derived from the ancient Greek noun , from verb , "I cease to exist," a combination of prefix , from preposition , "out," and of verb , "I am absent"....
 as Spirit watched Phobos disappear into Mars's shadow. Some of Spirits star gazing was designed to look for a predicted meteor shower

Meteor shower

Meteor showers, some of which are known as "meteor storms" , "meteor outbursts,"or "star storm are celestial events in which a number of meteors are observed to radiate from one point in the sky....
 caused by Halley's Comet, and although at least four imaged streaks were suspect meteors, they could not be unambiguously differentiated from those caused by cosmic rays.

A transit of Mercury from Mars

Transit of Mercury from Mars

A astronomical transit of Mercury across the Sun as seen from Mars takes place when the planet Mercury passes directly between the Sun and Mars, obscuring a small part of the Sun's disc for an observer on Mars....
 took place on January 12, 2005 from about 14:45 UTC

Coordinated Universal Time

Coordinated Universal Time is a time standard based on International Atomic Time with leap seconds added at irregular intervals to compensate for the Earth's slowing rotation....
 to 23:05 UTC. Theoretically, this could have been observed by both Spirit and Opportunity

Opportunity rover

MER-B , known as Opportunity, is the second of the two rover s of NASA's Mars Exploration Rover Mission. It landed successfully at Meridiani Planum on Mars on January 25, 2004 05:05 Ground UTC , three weeks after its twin Spirit rover had landed on the other side of the planet....
; however, camera resolution did not permit seeing Mercury's 6.1" angular diameter. They were able to observe transits of Deimos

Deimos (moon)

Deimos , is the smaller and outer of Mars? two natural satellite . It is named after Deimos , a figure representing dread in Greek Mythology. Its Astronomical_naming_conventions#Natural_satellites_of_planets is ....
 across the Sun, but at 2' angular diameter, Deimos is about 20 times larger than Mercury's 6.1" angular diameter. Ephemeris data generated by JPL Horizons indicates that Opportunity would have been able to observe the transit from the start until local sunset at about 19:23 UTC Earth time, while Spirit would have been able to observe it from local sunrise at about 19:38 UTC until the end of the transit.

Software upgrades

On January 4, 2007, both rovers received new flight software to the onboard computers. The update was received just in time for the third anniversary of their landing. The new systems let the rovers decide whether or not to transmit an image, and whether or not to extend their arms to examine rocks, which would save much time for scientists as they would not have to sift through hundreds of images to find the one they want, or examine the surroundings to decide to extend the arms and examine the rocks.

Equipment failures

Although both rovers have passed their original mission time of 90 sols many times over, the extended time on the suface and therefore additional stress on components has resulted in some issues developing.

On sol 779, the right front wheel ceased working after having covered on Mars. Engineers began driving the rover backwards, dragging the dead wheel. Ironically, although this has resulted in changes to driving techniques the dragging effect has also had a positive effect in the fact that the wheel dragging has partially cleared soil away on the surface as the rover travels and allows for imaging areas that would normally be covered in soil.

The grinding surface of the Rock Abrasion Tool has also worn down, and the device can only be used to brush targets.

All of the other science instruments and engineering cameras continue to function. The Mössbauer spectrometer takes much longer to produce results than it did earlier in the mission because of the decay of its radioactive source.

Honors

Honoring Spirits great contribution to the exploration of Mars, the asteroid

Asteroid

Asteroids, sometimes called minor planets or planetoids, are small Solar System bodies in orbit around the Sun, smaller than planets but larger than meteoroids....
 37452 Spirit

37452 Spirit

Asteroid 37452 Spirit was discovered on September 24, 1960 by Ingrid van Houten-Groeneveld, Cornelis Johannes van Houten, and Tom Gehrels. The asteroid was spotted by examining photographic plates of images taken by telescopes at the Palomar Observatory....
 has been named after it. The name was proposed by Ingrid van Houten-Groeneveld

Ingrid van Houten-Groeneveld

Ingrid van Houten-Groeneveld is a Netherlands astronomer.In a jointly-credited trio with Tom Gehrels and her husband Cornelis Johannes van Houten, she was an extremely prolific discoverer of many thousands of asteroids....
 who along with Cornelis Johannes van Houten

Cornelis Johannes van Houten

Cornelis Johannes van Houten was a Dutch astronomer, sometimes referred to as Kees van Houten.Born in The Hague, he spent his entire career at Leiden University except for a brief period as research assistant at Yerkes Observatory....
 and Tom Gehrels

Tom Gehrels

Tom Gehrels is an American astronomer, Professor Planetary Sciences, and Astronomer at the University_Of_Arizona, Tucson.Gehrels pioneered the first photometric system of asteroids in the 50s, and wavelength dependence of polarization of stars and planets in the 60s, each resulting in an extended sequence of papers in the Astronomical_Jour...
 discovered the asteroid on September 24, 1960.

Ruben H. Fleet Museum and the Liberty Science Center

Liberty Science Center

'Liberty Science Center' is an interactive science museum and learning center located in Liberty State Park in Jersey City, New Jersey.The center, which first opened in 1993 as New Jersey's first major state science museum, has science exhibits, the world's largest IMAX Dome theater, numerous educational resources, and the original Hoberma...
 also has an IMAX show called Roving Mars that documents the journey of both Spirit and Opportunity, using both CG and actual imagery.

See also

• Exploration of Mars
  Exploration of Mars
  
  The exploration of Mars has been an important part of the space exploration programs of the Soviet Union , the United States, Europe, and Japan....
  
• Space exploration
  Space exploration
  
  Space exploration is the use of astronomy and space technology to explore outer space. Physical exploration of space is conducted both by human spaceflights and by robotic spacecraft....
  
• Unmanned space missions
• Autonomous robot
  Autonomous robot
  
  Autonomous robots are robots which can perform desired tasks in unstructured environments without continuous human guidance. Many kinds of robots have some degree of autonomy....
  
• Opportunity rover
  Opportunity rover
  
  MER-B , known as Opportunity, is the second of the two rover s of NASA's Mars Exploration Rover Mission. It landed successfully at Meridiani Planum on Mars on January 25, 2004 05:05 Ground UTC , three weeks after its twin Spirit rover had landed on the other side of the planet....
  
• Comparison of embedded computer systems on board the Mars rovers
  Comparison of embedded computer systems on board the Mars rovers
  
  The embedded system computer systems on board the various rovers sent to planet Mars by organisations such as the NASA have to withstand the high radiation levels and large temperature changes in space, and for this reason their computational resources are limited....
  

External links

JPL, MSSS, and NASA links

• by
• , NASA JPL's Planetary Photojournal for Spirit
• for MER News Briefings at JPL
• Wikisource:NASA MER press briefings

Other links

• last updated May 2004
• , a site that tracks time on Mars.
• (requires download, last update October 25, 2004)
• last update 2006
• (not working as of 2008-06-04)
• - News, status, technical info, history, and more.
• , 15 March 2005
• , 03 April 2006
• as of 2008-06-04 last updated 2008-06-04
• , satire from The Onion
  The Onion
  
  'The Onion' is an United States "news satire" organization. It features satire articles reporting on international, national, and local news as well as an entertainment newspaper and website known as The A.V....
  , October 24, 2006
• , nasatech.net, Nov 23 to Dec. 5, 2005 (long download, uses Java
  Java
  
  Java is an island of Indonesia and the site of its Capital city, Jakarta. Once the centre of powerful Hindu kingdoms, The spread of Islam in Indonesia , and the core of the colonial Dutch East Indies, Java now plays a dominant role in the economic and political life of Indonesia....
  )
• , nasatech.net, Nov 23 to Dec. 5, 2005 (long download, uses Java
  Java
  
  Java is an island of Indonesia and the site of its Capital city, Jakarta. Once the centre of powerful Hindu kingdoms, The spread of Islam in Indonesia , and the core of the colonial Dutch East Indies, Java now plays a dominant role in the economic and political life of Indonesia....
  )