Spirit landed successfully within the impact crater Gusev on Mars at 04:35 Ground UTC on January 4, 2004, three weeks before its twin, Opportunity (MER-B), which landed on the other side of the planet. Its name was chosen through a NASA-sponsored student essay competition. The rover became stuck in a sand trap in late 2009 at an angle that hampered recharging of its batteries; its last communication with Earth was sent on March 22, 2010.
The rover completed its planned 90-sol mission, slightly less than 92.5 Earth days. Aided by cleaning events that resulted in more energy from its solar panels, Spirit went on to function effectively over twenty times longer than NASA planners expected.
Spirit also logged 7.73 km of driving instead of the planned 600 m, allowing more extensive geological analysis of Martian rocks and planetary surface features. Initial scientific results from the first phase of the mission, the 90-sol prime mission, were published in a special issue of the journal Science.
More information: NASA
On May 1, 2009 (5 years, 3 months, 27 Earth days after landing; 21 times the planned mission duration), Spirit became stuck in soft sand. This was not the first of the mission's embedding events and for the following eight months NASA carefully analysed the situation, running Earth-based theoretical and practical simulations, and finally programming the rover to make extrication drives in an attempt to free itself.
These efforts continued until January 26, 2010 when NASA officials announced that the rover was likely irrecoverably obstructed by its location in soft sand, though it continued to perform scientific research from its current location.
The rover continued in a stationary science platform role until communication with Spirit stopped on March 22, 2010. JPL continued to attempt to regain contact until May 24, 2011, when NASA announced that efforts to communicate with the unresponsive rover had ended, calling the mission complete. A formal farewell took place at NASA headquarters shortly thereafter.
The primary surface mission for Spirit was planned to last at least 90 sols. The mission received several extensions and lasted about 2,208 sols.
On August 11, 2007, Spirit obtained the second-longest operational duration on the surface of Mars for a lander or rover at 1282 Sols, one sol longer than the Viking 2 lander. Viking 2 was powered by a nuclear cell, whereas Spirit is powered by solar arrays. Until Opportunity overtook it on May 19, 2010, the Mars probe with the longest operational period was Viking 1 that lasted for 2245 Sols on the surface of Mars.
On March 22, 2010, Spirit sent its last communication, thus falling just over a month short of surpassing Viking 1's operational record. An archive of weekly updates on the rover's status can be found at the Spirit Update Archive.
More information: Time
Spirit's total iodometry as of March 22, 2010 is 7,730.50 meters.
The scientific objectives of the Mars Exploration Rover mission were to:
-Search for and characterize a variety of rocks and soils that hold clues to past water activity. In particular, samples sought will include those that have minerals deposited by water-related processes such as precipitation, evaporation, sedimentary cementation or hydrothermal activity.
-Determine the distribution and composition of minerals, rocks, and soils surrounding the landing sites.
-Determine what geologic processes 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 instruments. This will help determine the accuracy and effectiveness of various instruments that survey Martian geology from orbit.
-Search for iron-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 and textures of rocks and soils and determine the processes that created them.
-Search for geological clues to the environmental conditions that existed when liquid water was present.
-Assess whether those environments were conducive to life.
NASA sought evidence of life on Mars, beginning with whether the Martian environment was ever suitable for life. Life forms known to science require water, so the history of water on Mars is a critical piece of knowledge. Although the Mars Exploration Rovers did not have the ability to detect life directly, they offered very important information on the habitability of the environment during the planet's history.
More information: Wired
new scientific understanding of climate change,
of how planet-wide processes can make
a warm and wet world into a barren landscape.
By exploring and understanding Mars,
we may gain key insights
into the past and future of our own world.
Buzz Aldrin
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