Spirit Rover

                         SPIRIT ROVER   

 

ABOUT THE MISSION:

 

Spirit, also known as MER-A (Mars Exploration Rover – A) or MER-2, is a robotic rover on Mars, active from 2004 to 2010. It was one of two rovers of NASA's ongoing Mars Exploration Rover Mission. It landed successfully on Mars at 04:35 Ground UTC on January 4, 2004, three weeks before its twin, Opportunity (MER-B), landed on the other side of the planet. Its name was chosen through a NASA-sponsored student essay competition. The rover became stuck in late 2009, and its last communication with Earth was sent on March 22, 2010.

 

Scientific Instrument(s)

- Panoramic camera (Pancam)
- Microscopic Imager (MI)
- Miniature Thermal Emission Spectrometer (Mini-TES)
- Mossbauer Spectrometer (MB)
- Alpha Particle X-ray Spectrometer (APXS)
- Rock Abrasion Tool (RAT)
- Magnet arrays
- Hazard Avoidance Cameras (Hazcams)
- Navigation Cameras (Navcams) 

 

OBJECTIVES: 

 

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 the question of 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.
 

INSTRUMENTS DESCRIPTION:

 

• Panoramic Camera (Pancam) – examines the texture, color, mineralogy, and structure of the local terrain.
• Navigation Camera (Navcam) – monochrome with a higher field of view but lower resolution, for navigation and driving.
• Miniature Thermal Emission Spectrometer (Mini-TES) – identifies promising rocks and soils for closer examination, and determines the processes that formed them.
• Hazcams, two B&W cameras with 120 degree field of view, that provide additional data about the rover's surroundings.

The rover arm holds the following instruments

• Mössbauer spectrometer (MB) MIMOS II – used for close-up investigations of the mineralogy of iron-bearing rocks and soils.
• Alpha particle X-ray spectrometer (APXS) – close-up analysis of the abundances of elements that make up rocks and soils.
• Magnets – for collecting magnetic dust particles.
• Microscopic Imager (MI) – obtains close-up, high-resolution images of rocks and soils.
• Rock Abrasion Tool (RAT) – exposes fresh material for examination by instruments on board

 MISSION OVERVIEW:

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 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. Spirit's total odometry as of March 22, 2010 (sol 2210) is 7,730.50 meters 

 

 FIRST COLOURED IMAGE OF SPIRIT:

 

To the right is the first color image derived from images taken by the panoramic camera on the Mars Exploration Rover Spirit. It was the highest resolution image taken on the surface of another planet. According to the camera designer Jim Bell of Cornell University, the panoramic mosaic consists of four pancam images high by three wide. The picture shown originally had a full size of 4,000 by 3,000 pixels. However, a complete pancam panorama is even 8 times larger than that, and could be taken in stereo (i.e., two complete pictures, making the resolution twice as large again.) The colors are fairly accurate. (For a technical explanation, see colors outside the range of the human eye.)
The MER pancams are black-and-white instruments. Thirteen rotating filter wheels produce multiple images of the same scene at different wavelengths. Once received on Earth, these images can be combined to produce color images.

 

FIRST GRINDING OF ROCKS:

 

The round, shallow depression in this image resulted from the first intentional grinding of a rock on Mars. The Rock Abrasion Tool (aka "RAT") on NASA's Spirit rover ground off the surface of a patch 45.5 millimeters (1.79 in) in diameter on a rock called Adirondack during sol 32 (February 6, 2004). The hole is 2.65 millimeters (0.104 in) 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 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."
 

END OF MISSION:

 

JPL continued attempts to regain contact with Spirit until May 25, 2011, when NASA announced the end of contact efforts and the completion of the mission.According to NASA, the rover likely experienced excessively cold "internal temperatures" due to "inadequate energy to run its survival heaters" that, in turn, was a result of "a stressful Martian winter without much sunlight." Many critical components and connections would have been "susceptible to damage from the cold." Assets that had been needed to support Spirit were transitioned to support Spirit's "still-active twin", Opportunity, as well as the next-generation Mars rover Curiosity. Two NASA Mars orbiters and the Deep Space Network of antennas were prepared for the Curiosity launch that took place on November 26, 2011

DISCOVERIES OF MISSION:

The rocks on the plains of Gusev are a type of basalt. They contain the minerals olivine, pyroxene, plagioclase, and magnetite, and they look like volcanic basalt as they are fine-grained with irregular holes (geologists would say they have vesicles and vugs)

 

Much of the soil on the plains came from the breakdown of the local rocks. Fairly high levels of nickel were found in some soils; probably from meteorites.
Analysis shows that the rocks have been slightly altered by tiny amounts of water. Outside coatings and cracks inside the rocks suggest water deposited minerals, maybe bromine compounds. All the rocks contain a fine coating of dust and one or more harder rinds of material. One type can be brushed off, while another needed to be ground off by the Rock Abrasion Tool (RAT).
There are a variety of rocks in the Columbia Hills (Mars), some of which have been altered by water, but not by very much water.
The dust in Gusev Crater is the same as dust all around the planet. All the dust was found to be magnetic. Moreover, Spirit found the magnetism was caused by the mineral magnetite, especially magnetite that contained the element titanium. One magnet was able to completely divert all dust hence all Martian dust is thought to be magnetic. The spectra of the dust was similar to spectra of bright, low thermal inertia regions like Tharsis and Arabia that have been detected by orbiting satellites. A thin layer of dust, maybe less than one millimeter thick covers all surfaces. Something in it contains a small amount of chemically bound water.