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Mars Exploration Rover

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Mars Exploration Rover



 
 
NASA
NASA

The National Aeronautics and Space Administration is an agency of the Federal government of the United States, responsible for the nation's public list of space agencies....
's Mars Exploration Rover (MER) Mission is an ongoing robotic mission of exploring Mars, that began in 2003 with the sending of two rover
Rover (space exploration)

A rover is a space exploration vehicle designed to move across the surface of a planet or other astronomical body. Some rovers have been designed to transport members of a human spaceflight crew; others have been partially or fully autonomous robots....
s — Spirit
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....
 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....
 — to explore the Martian surface and geology
Geology

Geology is the science and study of the solid and liquid matter that constitute the Earth. The field of geology encompasses the study of the composition, structural geology, physical properties, dynamics, and History of the Earth of Earth materials, and the processes by which they are formed, moved, and changed....
.

Primary among the mission's scientific goals is to search for and characterize a wide range of rocks
Rock (geology)

In geology, rock is a naturally occurring solid aggregate of minerals and/or mineraloids.The Earth's outer solid layer, the lithosphere, is made of rock....
 and soil
Soil

Soil is the naturally occurring, unconsolidated or loose covering on the Earth's surface. Soil is composed of particles of broken rock that have been altered by chemical and environmental processes including weathering and erosion....
s that hold clues to past water activity on Mars.






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Encyclopedia


Nasa Mars Rover
NASA
NASA

The National Aeronautics and Space Administration is an agency of the Federal government of the United States, responsible for the nation's public list of space agencies....
's Mars Exploration Rover (MER) Mission is an ongoing robotic mission of exploring Mars, that began in 2003 with the sending of two rover
Rover (space exploration)

A rover is a space exploration vehicle designed to move across the surface of a planet or other astronomical body. Some rovers have been designed to transport members of a human spaceflight crew; others have been partially or fully autonomous robots....
s — Spirit
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....
 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....
 — to explore the Martian surface and geology
Geology

Geology is the science and study of the solid and liquid matter that constitute the Earth. The field of geology encompasses the study of the composition, structural geology, physical properties, dynamics, and History of the Earth of Earth materials, and the processes by which they are formed, moved, and changed....
.

Primary among the mission's scientific goals is to search for and characterize a wide range of rocks
Rock (geology)

In geology, rock is a naturally occurring solid aggregate of minerals and/or mineraloids.The Earth's outer solid layer, the lithosphere, is made of rock....
 and soil
Soil

Soil is the naturally occurring, unconsolidated or loose covering on the Earth's surface. Soil is composed of particles of broken rock that have been altered by chemical and environmental processes including weathering and erosion....
s that hold clues to past water activity on Mars. The mission is part of NASA's Mars Exploration Program which includes three previous successful landers: the two Viking
Viking program

NASA's Viking program consisted of a pair of space probes sent to Mars , Viking 1 and Viking 2. Each vehicle was composed of two main parts, an orbiter designed to photograph the surface of Mars from orbit, and a lander designed to study the planet from the surface....
 landers in 1976 and Pathfinder
Mars Pathfinder

The Mars Pathfinder was launched on December 4, 1996 by NASA aboard a Delta II just a month after the Mars Global Surveyor was launched. After a 7-month voyage it landed on Ares Vallis, in a region called Chryse Planitia on Mars, on 4 July 1997....
 in 1997.

The total cost of building, launching, landing and operating the rovers on the surface for the initial 90 day primary mission was about US$820 million. Since the rovers are still functioning almost five years after landing, mission funding has been extended to "possibly through 2009". In July of 2007, Martian dust storms blocked sunlight to the rovers and threatened the ability of the craft to gather energy through their solar panel
Photovoltaic module

In the field of photovoltaics, a photovoltaic module or photovoltaic panel is a packaged interconnected assembly of photovoltaic cells, also known as solar cells....
s, causing engineers to fear that one or both of them might be permanently disabled. Luckily for the rovers, the dust storms lifted, allowing them to resume operations.

In recognition of the vast amount of scientific information
Scientific information from the Mars Exploration Rover mission

NASA's 2003 Mars Exploration Rover Mission has amassed an enormous amount of scientific information related to the Martian geology and atmosphere, as well as providing some astronomical observations from Mars....
 amassed by both rovers, two 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....
s have been named in their honor: 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....
 and 39382 Opportunity
39382 Opportunity

Asteroid 39382 Opportunity 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 taken by telescopes at the Palomar Observatory....
.

The mission is managed for NASA
NASA

The National Aeronautics and Space Administration is an agency of the Federal government of the United States, responsible for the nation's public list of space agencies....
 by the Jet Propulsion Laboratory
Jet Propulsion Laboratory

Jet Propulsion Laboratory is a List of federally funded research and development centers and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, California, United States....
, which designed, built and is operating the rovers.

Objectives

The scientific objectives of the Mars Exploration Rover mission are to:

  • 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....
    .


During the next two decades, NASA will conduct several missions to address whether life ever arose on Mars. The search begins with determining whether the Martian environment was ever suitable for life. Life, as we understand it, requires water, so the history of water on Mars is critical to finding out if the martian environment was ever conducive to life. Although the Mars Exploration Rovers do not have the ability to detect life directly, they are offering very important information on the habitability of the environment in the planet's history.

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On January 21, 2004, the Deep Space Network
Deep Space Network

The Deep Space Network, or DSN, is an international Wiktionary:network of communication facilities that supports interplanetary spacecraft missions, and radio astronomy and radar astronomy observations for the exploration of the solar system and the universe....
 lost contact with Spirit, for reasons originally thought to be related to a thunderstorm
Thunderstorm

File:FoggDam-NT.jpgA thunderstorm, also known as an electrical storm or a lightning storm, is a form of weather characterized by the presence of lightning and its effect: thunder....
 over Australia
Australia

Australia, officially the Commonwealth of Australia, is a country in the southern hemisphere comprising the Australia of the world's smallest continent, the major island of Tasmania, and numerous list of islands of Australia in the Indian Ocean and Pacific Oceans....
. The rover transmitted a message with no data, but later that day missed another communications session with the Mars Global Surveyor
Mars Global Surveyor

The Mars Global Surveyor was a US spacecraft developed by NASA's Jet Propulsion Laboratory and launched November 1996. It began the United States's return to Mars after a 20-year absence....
. The next day, JPL managed to receive a beep from the rover, indicating that it was in fault mode. On the 23rd, the flight team succeeded in making the rover send. The fault was believed to have been caused by an error in the rover's 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....
 subsystem. The rover did not perform any scientific activities for 10 days, while engineers updated its software and ran tests. The problem was corrected by reformatting Spirit's flash memory and upgrading the software with a patch to avoid memory overload; Opportunity was also upgraded with the patch as a precaution. Spirit returned to full scientific operations by 5 February. This has to date been the most serious anomaly in the mission.

On March 23, 2004, a news conference was held announcing "major discoveries" of evidence of past liquid 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....
 on the Martian surface. A delegation of scientists showed pictures and data revealing a stratified pattern and cross bedding in the rocks of the outcrop inside a crater in Meridiani Planum
Meridiani Planum

Meridiani Planum is a plain located 2 degrees south of Mars ' equator , in the westernmost portion of Terra Meridiani. It hosts a rare occurrence of gray crystalline hematite....
, landing site of MER-B, Opportunity, suggesting that water once flowed in the region. The irregular distribution of chlorine
Chlorine

Chlorine...
 and bromine
Bromine

Bromine , , meaning "stench " ), is a chemical element with the symbol Br and atomic number 35. A halogen element, bromine is a reddish-brown Volatility liquid at Standard conditions for temperature and pressure that is intermediate in reactivity between chlorine and iodine....
 also suggests that the place was once the shoreline of a salty sea, now evaporated.

On April 8, 2004, NASA announced that it was extending the mission life of the rovers from 3 to 8 months. It immediately provided additional funding of US $15 million through September, and $2.8 million per month for continuing operations.

On April 30, 2004, Opportunity arrived at Endurance crater, taking about 5 days to drive the 200 meters.

On September 22, 2004, NASA announced that it was extending the mission life of the rovers for another 6 months. Opportunity was to leave Endurance crater, visit its discarded heat shield, and proceed to Victoria crater. Spirit was to attempt to climb to the top of the Columbia Hills.

On April 6, 2005, with the two rovers still functioning well, NASA announced another 18 month extension of the mission to September 2006. Opportunity was to visit the "Etched Terrain" and Spirit was to climb a rocky slope toward the top 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 ....
.

Sol582a P2299 L456 A590r1 Br
On August 21, 2005, Spirit reached the summit of Husband Hill after 581 sols and a journey of 4.81 kilometers (2.99 mi).

Spirit celebrated its one Martian year anniversary (669 sols or 687 Earth days) on November 20, 2005. Opportunity celebrated its anniversary on December 12. At the beginning of the mission, it was expected that the rovers would not survive much longer than 90 days. The Columbia Hills were "just a dream" according to rover driver Chris Leger.

On February 7, 2006,
Spirit reached the semicircular rock formation known as 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....
. It is a layered rock outcrop that puzzles and excites scientists. It is thought that its rocks are explosive volcanic deposits, though other possibilities exist, including impact deposits or wind/water borne sediment.

On March 13, 2006,
Spirit's front right wheel ceased working while the rover was moving itself to 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 ....
. Her drivers attempted to drag the dead wheel behind Spirit, but this only worked until reaching an impassable sandy area on the lower slopes. Drivers directed
Spirit to a smaller sloped feature, dubbed "Low Ridge Haven", where she spent the long Martian winter, waiting for spring and increased solar power levels suitable for driving.

On September 26, 2006, Spaceflight Now reported that NASA has extended mission for the two rovers through September 2007. On September 27, 2006,
Opportunity reached the rim of Victoria crater.

Spirit had lasted over 1,000 Martian days exploring Gusev Crater as of October 25, 2006. Opportunity had lasted over 1,000 Martian days exploring Meridiani Planum as of November 16, 2006. As of January 24, 2007, the rovers had lasted on Mars more than three years. (Although Opportunity landed on January 25, the year 2004 was a leap year
Leap year

A leap year is a year containing one or more extra days in order to keep the calendar year synchronized with the astronomical year or seasonal year....
.)

On February 6, 2007,
Opportunity became the first spacecraft to traverse 10,000 meters - 10 kilometers - on the surface of Mars.

On June 28, 2007,
Opportunity was poised to enter Victoria Crater from its perch on the rim of Duck Bay., but due to extensive dust storms, it was indefinitely delayed until the dust had cleared and power returned to safe levels.

On August 28, 2007,
Spirit and Opportunity resumed driving after hunkering down during raging dust storms that limited solar power to a level that nearly caused the permanent failure of both rovers.

On October 1, 2007, both
Spirit and Opportunity entered their fifth mission extension that could possibly extend operations into 2009, allowing the rovers to have spent five years exploring the Martian surface, pending their continued survival.

On January 3, 2008,
Spirit entered its fourth year of exploration of Gusev crater
Gusev crater

Gusev is a Impact crater on the planet Mars and is located at 175.4?E 14.6?S. The crater is about 170 kilometers in diameter and formed approximately three to four billion years ago....
.

On January 25, 2008,
Opportunity entered its fourth year of exploration of Meridiani Planum
Meridiani Planum

Meridiani Planum is a plain located 2 degrees south of Mars ' equator , in the westernmost portion of Terra Meridiani. It hosts a rare occurrence of gray crystalline hematite....
.

On August 26, 2008,
Opportunity began to climb out of Victoria Crater amidst concerns that power spikes, similar to those seen on Spirit before the failure of its right-front wheel, might prevent Opportunity from ever being able to leave the crater in the event of the failure of one of its wheels. Project scientist Bruce Banerdt has also said, "We've done everything we entered Victoria Crater to do and more." Opportunity will return to the plains in order to characterize Meridiani Planum's vast diversity of rocks--some of which may have been blasted out of craters such as Victoria. The rover had been exploring Victoria Crater since September 11, 2007.

On August 29, 2008,
Opportunity succeeded in climbing out of Victoria Crater, using the same route it took on the way in.

On January 3, 2009,
Spirit marked 5 years on Mars. Since landing on Mars the two rovers had collectively sent back 250,000 images and traveled over 21 kilometers (13 miles).

Spacecraft design

Delta Ii Rocket
Mer Cruise Stage Diagram
Opportunity Cruise Stage
Mars Rover Aeroshell
The Mars Exploration Rover was designed to be stowed in the nose of a Delta II rocket. Each spacecraft consists of several components:
  • Rover: 185 kg (408 lb)
  • Lander: 348 kg (767 lb)
  • Backshell / Parachute: 209 kg (461 lb)
  • Heat Shield: 78 kg (172 lb)
  • Cruise Stage: 193 kg (425 lb)
  • Propellant: 50 kg (110 lb)
Total mass is 1,063 kg (2,343 lb).

Cruise stage

The cruise stage is the component of the spacecraft that is used for travel from Earth to Mars. It is very similar to the Mars Pathfinder in design and is approximately 2.65 meters
Metre

The metre or meter is a Unit of measurement of length. It is the SI base unit of length in the metric system and in the International System of Units , used around the world for general and scientific purposes....
 (8.7 ft) in diameter
Diameter

In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints are on the circle....
 and 1.6 m (5.2 ft) tall including the entry vehicle (see below).

The primary structure is aluminium
Aluminium

Aluminium or aluminum is a silvery white and ductile member of the boron group of chemical elements. It has the symbol Al; its atomic number is 13....
 with an outer ring of ribs covered by the solar panel
Photovoltaic module

In the field of photovoltaics, a photovoltaic module or photovoltaic panel is a packaged interconnected assembly of photovoltaic cells, also known as solar cells....
s, which are about 2.65 m (8.7 ft) in diameter. Divided into five sections, the solar arrays can provide up to 600 watt
WATT

WATT is a radio station broadcasting a News radio-Talk radio-Sports radio format. Licensed to Cadillac, Michigan, it first began broadcasting in 1945....
s of power near Earth and 300 W at Mars.

Heaters and multi-layer insulation
Multi-layer insulation

Multi-layer insulation, or MLI, is thermal insulation composed of multiple layers of thin sheets often used in spacecraft. It is mainly intended to reduce losses by thermal radiation....
 keep the electronics "warm". A freon
Freon

Freon is DuPont's trade name for its odorless, colorless, nonflammable, and noncorrosive chlorofluorocarbon and hydrochlorofluorocarbon refrigerants, which are used in air conditioning, refrigeration and some automatic fire-fighting systems....
 system removes heat from the flight computer and communications hardware inside the rover so they do not overheat. Cruise avionics systems allow the flight computer to interface with other electronics such as the sun sensors, star scanner and heaters.

Navigation
The star scanner (with a backup system) and sun sensor allowed the spacecraft to know its orientation in space by analyzing the position of the Sun and other stars in relation to itself. Sometimes the craft could be slightly off course; this was expected given the 500 million kilometer (320 million mile) journey. Thus navigators planned up to six trajectory correction maneuvers, along with health checks.

To ensure the spacecraft arrived at Mars in the right place for its landing, two light-weight, aluminium-lined tanks carried about 31 kg (about 68 lb) of hydrazine
Hydrazine

Hydrazine is a chemical compound with the chemical formula N2H4. It is a colourless liquid with an ammonia-like odor and is derived from the same industrial chemistry processes that manufacture ammonia....
 propellant
Propellant

A propellant is a material that is used to move an object. This will often involve a chemical reaction. It may be a gas, liquid, Plasma , or, before the chemical reaction, a solid....
. Along with cruise guidance and control systems, the propellant allowed navigators to keep the spacecraft on course. Burns and pulse firings of the propellant allowed three types of maneuvers:
  • An axial burn uses pairs of thrusters to change spacecraft velocity;
  • A lateral burn uses two "thruster clusters" (four thrusters per cluster) to move the spacecraft "sideways" through seconds-long pulses;
  • Pulse mode firing uses coupled thruster pairs for spacecraft precession
    Precession

    Precession refers to a change in the direction of the axis of a rotation object. In physics, there are two types of precession, torque-free and torque-induced, the latter being discussed here in more detail....
     maneuvers (turns).


Communication
The spacecraft used a high-frequency X band
X band

The X band is part of the microwave region of the electromagnetic spectrum. Its frequency range is from 7 to 12.5 GHz. The 10.7-12.5 GHz portion overlaps the Ku band....
 radio
Radio

Radio is the transmission of signals, by modulation of electromagnetic radiation with frequency below those of visible light.Electromagnetic radiation radio propagation by means of oscillating electromagnetic fields that pass through the air and the vacuum of space....
 wavelength
Wavelength

In physics, wavelength is the distance between repeating units of a propagating wave of a given frequency. It is commonly designated by the Greek language letter lambda ....
 to communicate, which allowed for less power and smaller antennas than many older craft, which used S band
S band

The S band ranges from 2 to 4 GHz, crossing the boundary between Ultra high frequency and Super high frequency at 3.0 GHz. It is part of the microwave band of the electromagnetic spectrum....
.

Navigators sent commands through two antennas on the cruise stage: a cruise low-gain antenna
Low-gain antenna

The low-gain antenna is an antenna with a broad radiowave beam width. This very wide beam allows for a more reliable signal that is best used in mountainous regions, where the signal will propagate reasonably well regardless of terrain....
mounted inside the inner ring, and a cruise medium-gain antenna in the outer ring. The low-gain antenna was used close to Earth. It is omni-directional, so the transmission power that reached Earth fell fast with increasing distance. As the craft moved closer to Mars, the Sun and Earth moved closer in the sky as viewed from the craft, so less energy reached Earth. Then, the spacecraft switched to the medium-gain antenna, which directed the same amount of transmission power into a tighter beam toward Earth.

During flight, the spacecraft was spin-stabilized
Gyroscope

A gyroscope is a device for measuring or maintaining orientation , based on the principles of angular momentum. The device is a spinning wheel or disk whose axle is free to take any orientation....
 with a spin rate of 2 rpm. Periodic updates kept antennas pointed toward Earth and solar panels toward Sun.

Aeroshell

The aeroshell formed a protective covering for the lander during the seven month voyage to Mars. Together with the lander and the rover, it constituted the "entry vehicle". Its main purpose was to protect the lander and the rover inside it from the intense heating of entry into the thin Martian atmosphere. It was based on the Mars Pathfinder and Mars Viking designs.

Parts
The aeroshell was made of two main parts: a heat shield
Heat shield

A heat shield is a protective layer on a spacecraft or ballistic missile that is designed to protect it from the high temperature of atmospheric entry, on a body with an atmosphere, such as Earth, Mars and Venus....
 and a backshell. The heat shield was flat and brownish, and protected the lander and rover from the intense heat from entry into the Martian atmosphere and acted as the first aerobrake for the spacecraft. The backshell was large, cone-shaped and painted white. It carried the parachute
Parachute

A parachute is a device used to slow the motion of an object through an atmosphere by creating Drag .Parachutes are made out of cloth, most commonly nylon....
 and several components used in later stages of entry, descent, and landing, including:

  • A parachute (stowed at the top of the backshell);
  • The backshell electronics and batteries that fire off pyrotechnic devices like separation nuts, rockets and the parachute mortar;
  • A Litton LN-200 Inertial Measurement Unit (IMU), which monitors and reports the orientation of the backshell as it swings under the parachute;
  • Three large solid rocket
    Solid rocket

    A solid rocket or a solid-fuel rocket is a rocket with a motor that uses Rocket fuel#Solid propellants . The earliest rockets were solid fueled, powered by gunpowder, used by the Science and technology in China and Inventions in the Muslim world in warfare as early as the 13th century....
     motors called RAD rockets (Rocket Assisted Descent), each providing about a ton of force (10 kilonewtons) for about 4 seconds;
  • Three small solid rockets called TIRS (mounted so that they aim horizontally out the sides of the backshell) that provide a small horizontal kick to the backshell to help orient the backshell more vertically during the main RAD rocket burn.


Composition
Built by the Lockheed Martin Astronautics Co. in Denver, Colorado, the aeroshell is made of an aluminium honeycomb structure sandwiched between graphite-epoxy face sheets. The outside of the aeroshell is covered with a layer of phenol
Phenol

Phenol, also known as carbolic acid, is a toxic, white crystalline solid with a sweet tarry odor, commonly referred to as a "hospital smell"....
ic honeycomb. This honeycomb is filled with an ablative
Ablation

Ablation is defined as the removal of material from the surface of an object by vaporization, chipping, or other erosion processes. The term occurs in space physics associated with atmospheric reentry, in glaciology, medicine and passive fire protection....
 material (also called an "ablator"), that dissipates heat generated by atmospheric friction.

The ablator itself is a unique blend of cork
Cork (material)

Cork material is a prime-subset of generic Cork cambium, harvested for commercial use primarily from the Cork Oak tree, Quercus suber, with Portugal producing 50% of cork worldwide....
 wood
Wood

Wood is an organic material; in the strict sense wood is produced as secondary xylem in the stems of woody plants, notably trees but also shrubs, etc....
, binder
Binder

The reaper-binder, or binder, was a farm implement that improved upon the reaper. The binder was invented in 1872 by Charles Withington....
 and many tiny silica glass spheres. It was invented for the heat shields flown on the Viking Mars lander missions. A similar technology was used in the first US manned space missions Mercury
Mercury program

Mercury Program might refer to:*the first successful American manned spaceflight program, Project Mercury*an American post-rock band, The Mercury Program...
, Gemini and Apollo. It was specially formulated to react chemically with the Martian atmosphere during entry and carry heat away, leaving a hot wake of gas behind the vehicle. The vehicle slowed from 19000 km/h
Kilometres per hour

The kilometre per hour is a physical unit of both speed and velocity . The unit symbol is km/h or km?h-1; however, the colloquial abbreviations "kph" and "kmph" are sometimes also used in English-speaking countries, in analogy to mph, although these are not in accordance with international scientific standards....
 (about 12000 mph
Miles per hour

The mile per hour is a physical unit of speed, expressing the number of Mile covered per hour.It is currently the Unit of measurement used for speed limits, and speeds, on roads in the United Kingdom and United States....
) to about 1600 km/h (1000 mph) in about a minute, producing about 60 m/s² (6
g
G-force

The g-force of an object is its acceleration relative to free-fall. The unit of measure used is informally but commonly known as the "gee" , symbolized as g . An acceleration of 1 g is generally considered as equal to standard gravity , which is defined as precisely metre per second square...
) of acceleration
Acceleration

File:Acceleration.JPGFile:Acceleration components.JPGIn physics, and more specifically kinematics, acceleration is the change in velocity over time....
 on the lander and rover.

The backshell and heat shield are made of the same materials, but the heat shield has a thicker 1/2 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....
 (12.7 mm) layer of the ablator. Also, instead of being painted, the backshell was covered with a very thin aluminized PET film
PET film (biaxially oriented)

Biaxially-oriented polyethylene terephthalate polyester film is used for its high tensile strength, chemical stability and Shape strength of materials, Transparency , reflective, gas and aroma barrier properties and electricity Electrical insulation....
 blanket to protect it from the cold of deep space. The blanket vaporized during Mars atmospheric entry.

Parachute

Parachute1
The parachute helped slow the spacecraft during entry, descent, and landing. It is located in the backshell.

Design
The 2003 parachute design was part of a long-term Mars parachute technology development effort and is based on the designs and experience of the Viking and Pathfinder missions. The parachute for this mission is 40% larger than Pathfinder's because the largest load for the Mars Exploration Rover is 80 to 85 kilonewton
Newton

The newton is the International System of Units SI derived unit of force, named after Isaac Newton in recognition of his work on classical mechanics....
s (kN) or 18,000 to when the parachute fully inflates. By comparison, Pathfinder's inflation loads were approximately 35 kN (about 8,000 lbf). The parachute was designed and constructed in South Windsor, Connecticut
South Windsor, Connecticut

South Windsor is a town in Hartford County, Connecticut, Connecticut, United States. The population was 24,412 at the 2000 United States Census....
 by Pioneer Aerospace (), the company that also designed the parachute for the
Stardust
Stardust (spacecraft)

Stardust is an United States interplanetary mission of the NASA Jet Propulsion Laboratory, whose primary purpose was to investigate the makeup of the comet Comet Wild 2 and its coma ....
mission.

Composition
The parachute is made of two durable, lightweight fabrics: polyester
Polyester

Polyester is a category of polymers which contain the ester functional group in their main chain. Although there are many polyesters, the term "polyester" as a specific material most commonly refers to polyethylene terephthalate ....
 and nylon
Nylon

Nylon is a generic designation for a family of synthetic polymers known generically as polyamides and first produced on February 28, 1935 by Wallace Carothers at DuPont....
. A triple bridle made of Kevlar
Kevlar

Kevlar is the registered trademark for a light, strong aramid synthetic fiber, related to other aramids such as Nomex and Technora.Developed at DuPont in 1965 by Stephanie Kwolek it was first commercially used in the early 1970s as a replacement for steel in racing tires....
 connects the parachute to the backshell.

The amount of space available on the spacecraft for the parachute is so small that the parachute had to be pressure packed. Before launch, a team tightly folded the 48 suspension lines, three bridle lines, and the parachute. The parachute team loaded the parachute in a special structure that then applied a heavy weight to the parachute package several times. Before placing the parachute into the backshell, the parachute was heat set to sterilize
Sterilization (microbiology)

Sterilization refers to any process that effectively kills or eliminates transmissible agents from a surface, equipment, article of food or medication, or biological culture medium....
 it.

Connected systems
Rocket Assisted Descent
Zylon Bridles: After the parachute was deployed at an altitude of about 10 km (6 miles) above the surface, the heatshield was released using 6 separation nuts and push-off springs. The lander then separated from the backshell and "rappelled" down a metal tape on a centrifugal braking system built into one of the lander petals. The slow descent down the metal tape placed the lander in position at the end of another bridle (tether), made of a nearly 20 m (65 ft) long braided Zylon
Zylon

Zylon is a trademarked name for a range of thermoset polyurethane synthetic polymer materials manufactured by the Toyobo Corporation. Zylon was invented and developed by SRI International in the 1980s....
.

Zylon is an advanced fiber material similar to Kevlar that is sewn in a webbing pattern (like shoelace material) to make it stronger. The Zylon bridle provides space for airbag deployment, distance from the solid rocket motor exhaust stream, and increased stability. The bridle incorporates an electrical harness that allows the firing of the solid rockets from the backshell as well as provides data from the backshell inertial measurement unit (which measures rate and tilt of the spacecraft) to the flight computer in the rover.

Rocket assisted descent (RAD): motors. Because the atmospheric density of Mars is less than 1% of Earth's, the parachute alone could not slow down the Mars Exploration Rover enough to ensure a safe, low landing speed. The spacecraft descent was assisted by rockets that brought the spacecraft to a dead stop 10–15 m (30–50 ft) above the Martian surface.

Radar altimeter unit: A radar
Radar

Radar is a system that uses electromagnetic radiation waves to identify the range, altitude, direction, or speed of both moving and fixed objects such as aircraft, ships, motor vehicles, weather formations, and terrain....
 altimeter
Altimeter

An altimeter is an instrument used to measure the altitude of an object above a fixed level. The measurement of altitude is called altimetry, which is related to the term bathymetry, the measurement of depth underwater....
 unit was used to determine the distance to the Martian surface. The radar's antenna is mounted at one of the lower corners of the lander tetrahedron. When the radar measurement showed the lander was the correct distance above the surface, the Zylon bridle was cut, releasing the lander from the parachute and backshell so that it was free and clear for landing. The radar data also enabled the timing sequence on airbag inflation and backshell RAD rocket firing.

Airbags

Airbags
Airbag
Airbag

An airbag is a Automobile safety device. It is an occupant restraint consisting of a flexible envelope designed to inflate rapidly in an automobile collision, to prevent vehicle occupants from striking hard interior objects such as steering wheels....
s used in the Mars Exploration Rover mission are the same type that Mars Pathfinder
Mars Pathfinder

The Mars Pathfinder was launched on December 4, 1996 by NASA aboard a Delta II just a month after the Mars Global Surveyor was launched. After a 7-month voyage it landed on Ares Vallis, in a region called Chryse Planitia on Mars, on 4 July 1997....
 used in 1997. They had to be strong enough to cushion the spacecraft if it landed on rocks or rough terrain and allow it to bounce across Mars' surface at freeway speeds after landing. The airbags had to be inflated seconds before touchdown and deflated once safely on the ground.

The airbags were made of Vectran
Vectran

Vectran is a manufactured fibre, spun from a liquid crystal polymer created by Celanese Acetate LLC and now manufactured by Kuraray Chemically it is an aromatic polyester....
, like those on Pathfinder. Vectran has almost twice the strength of other synthetic materials, such as Kevlar, and performs better in cold temperatures. Six 100 denier (10 mg/m) layers of Vectran protected one or two inner bladders of Vectran in 200 denier (20 mg/m). Using 100 denier (10 mg/m) leaves more fabric in the outer layers where it is needed, because there are more threads in the weave.

Each rover used four airbags with six lobes each, which were all connected. Connection was important, since it helped abate some of the landing forces by keeping the bag system flexible and responsive to ground pressure. The airbags were not attached directly to the rover, but were held to it by ropes crisscrossing the bag structure. The ropes gave the bags shape, making inflation easier. While in flight, the bags were stowed along with three gas generators that are used for inflation.

Lander

Opportunity Lander Petals Pia04848
The spacecraft lander is a protective "shell" that houses the rover, and together with the airbags, protects it from the forces of impact.

The lander is a tetrahedron
Tetrahedron

A tetrahedron is a polyhedron composed of four triangle faces, three of which meet at each vertex . A regular tetrahedron is one in which the four triangles are regular, or "equilateral", and is one of the Platonic solids....
 shape whose sides open like petals. It is strong and light, and made of beams and sheets. The beams consist of layers of graphite
Graphite

The mineral graphite is one of the allotropes of carbon. It was named by Abraham Gottlob Werner in 1789 from the Greek language ??afe?? : "to draw/write", for its use in pencils, where it is commonly called lead, as distinguished from the actual metallic element lead....
 fiber woven into a fabric that is lighter than aluminium and more rigid than steel
Steel

Steel is an alloy consisting mostly of iron, with a carbon content between 0.2% and 2.14% by weight , depending on grade. Carbon is the most cost-effective alloying material for iron, but various other alloying elements are used such as manganese, chromium, vanadium, and tungsten....
. Titanium fittings are glued and fitted onto the beams to allow it to be bolted together. The rover was held inside the lander by bolt
Bolt

Bolt may refer to:*Bolt...
s and special nuts that were released after landing with small explosives.

Uprighting
After the lander stopped bouncing and rolling on the ground, it came to rest on the base of the tetrahedron or one of its sides. Then, the sides open to make the base horizontal and the rover upright. The sides are connected to the base by hinges, each of which has a motor strong enough to lift the lander. The rover plus lander has a mass
Mass

In physical science, mass refers to the degree of acceleration a body acquires when subject to a force: bodies with greater mass are accelerated less by the same force....
 of about 533 kilograms (1,175 pound
Pound (mass)

The pound or pound-mass is a Units of measurement of massused in the Imperial unit, United States customary units and other systems of measurement....
s). The rover alone weighs about 185 kg (408 lb). The gravity on Mars is about 38% of Earth's, so the motor does not need to be as powerful as it would on Earth.

The rover contains accelerometer
Accelerometer

An accelerometer is a device for measuring acceleration and gravity.Single- and multi-axis models are available to detect magnitude and direction of the acceleration as a Euclidean vector quantity, and can be used to sense orientation, vibration and shock....
s to detect which way is down (toward the surface of Mars) by measuring the pull of gravity. The rover computer then commanded the correct lander petal to open to place the rover upright. Once the base petal was down and the rover was upright, the other two petals were opened.

The petals initially opened to an equally flat position, so all sides of the lander were straight and level. The petal motors are strong enough so that if two of the petals come to rest on rocks, the base with the rover would be held in place like a bridge above the ground. The base will hold at a level even with the height of the petals resting on rocks, making a straight flat surface throughout the length of the open, flattened lander. The flight team on Earth could then send commands to the rover to adjust the petals to create a safe path for the rover to drive off the lander and onto the Martian surface without dropping off a steep rock.

Moving the payload onto Mars
Mer Spirit Lander Pan Sol16 A18r1 Br2
The moving of the rover off the lander is called the egress phase of the mission. The rover must avoid having its wheels caught in the airbag material or falling off a sharp incline. To help this, a retraction system on the petals slowly drags the airbags toward the lander before the petals open. Small ramps on the petals fan out to fill spaces between the petals. They cover uneven terrain, rock obstacles, and airbag material, and form a circular area from which the rover can drive off in more directions. They also lower the step that the rover must climb down. They are nicknamed "batwings", and are made of Vectran cloth.

About three hours were allotted to retract the airbags and deploy the lander petals.

Rover design

Mer Vs
The rovers are six-wheeled, solar-powered robots which stand 1.5 m (4.9 ft) high, 2.3 m (7.5 ft) wide and 1.6 m (5.2 ft) long. They weigh 180 kg (400 lb), 35 kg (80 lb) of which is the wheel and suspension system.

Drive system

Each rover has six wheels mounted on a rocker-bogie
Rocker-bogie

The Rocker-Bogie system is the Suspension arrangement used in the Mars rovers for both the Mars Pathfinder and Mars Exploration Rover missions....
 suspension system that ensures wheels remain on the ground while driving over rough terrain. The design reduces the range of motion of the rover body by half, and allows the rover to go over obstacles or through holes that are more than a wheel diameter (250 mm or 10 inches) in size. Each wheel also has cleats, providing grip for climbing in soft sand and scrambling over rocks.

Each wheel has its own motor. The two front and two rear wheels each have individual steering motors. This allows the vehicle to turn in place, a full revolution, and to swerve and curve, making arching turns. The rover is designed to withstand a tilt of 45 degrees in any direction without overturning. However, the rover is programmed through its "fault protection limits" in its hazard avoidance software to avoid exceeding tilts of 30 degrees.

Each rover can spin one of its front wheels in place to grind deep into the terrain. It is to remain motionless while the digging wheel is spinning.

The rover has a top speed on flat hard ground of 50 mm/s (2 in/s). But its average speed is 10 mm/s because its hazard avoidance software causes it to stop every 10 seconds for 20 seconds to observe and understand the terrain it has driven into.

Power and electronic systems


When fully illuminated, the rover triplejunction
Multijunction photovoltaic cell

Multijunction photovoltaic cells are a sub-class of solar cell or photovoltaic cell developed for higher efficiency. These multijunction cells consist of multiple thin films produced using molecular beam epitaxy and / or Metalorganic vapour phase epitaxy....
  solar arrays generate about 140 watts for up to four hours per Martian day (sol
Timekeeping on Mars

Various schemes have been used or proposed to keep track of time and date on the planet Mars independently of Earth time and calendars.Mars has an axial tilt and a rotation period similar to those of Earth....
). The rover needs about 100 watts to drive. Its power system includes two rechargeable lithium ion batteries weighing 7.15 kg (16 pounds) each, that provide energy when the sun is not shining, especially at night. Over time, the batteries will degrade and will not be able to recharge to full capacity.

For comparison, the future Mars Science Laboratory
Mars Science Laboratory

The Mars Science Laboratory is a NASA rover scheduled to be launched between October and December 2011 and perform the first-ever precision landing on Mars....
 is expected to last approximately one Martian year using radioisotope thermoelectric generator
Radioisotope thermoelectric generator

A radioisotope thermoelectric generator is an electrical generator which obtains its power from radioactive decay. In such a device, the heat released by the decay of a suitable radioactivity material is converted into electricity by the Seebeck effect using an array of thermocouples....
s to power its many instruments. Solar panels are also being considered, but RTGs provide versatility to work in dark environments and high latitudes where solar energy is not an efficient way to generate power.

It was thought that by the end of the 90-sol mission, the capability of the solar arrays to generate power would likely be reduced to about 50 watts. This was due to anticipated dust coverage on the solar arrays, and the change in season. But over three Earth years later, the rovers' power supplies hovered between 300 watt-hour
Watt-hour

The kilowatt hour, also written kilowatt-hour, is a unit of energy.Energy delivered by electric utilities is usually expressed and charged for in kWh....
s and 900 watt-hours per day, depending on dust coverage. Cleaning events (probably wind) have occurred more often than NASA expected, keeping the arrays relatively free of dust and extending the life of the mission. During a 2007 global dust storm on Mars, both rovers experienced some of the lowest power of the mission; Opportunity dipped to a mere 128 watt-hours.

The rovers run a VxWorks
VxWorks

VxWorks is a real-time operating system operating system made and sold by Wind River Systems of Alameda, California, California, USA.VxWorks is designed for use in embedded systems....
 embedded operating system
Embedded operating system

An embedded operating system is an operating system for embedded system. These operating systems are designed to be very compact and efficient, forsaking many functions that non-embedded computer operating systems provide, and which may not be used by the specialized applications they run....
 on a radiation-hardened 20 MHz RAD6000
RAD6000

The RAD6000 radiation hardening single board computer, based on the IBM RISC Single Chip central processing unit, was manufactured by IBM Federal Systems....
 CPU
Central processing unit

A central processing unit is an electronic circuit that can execute computer programs. This broad definition can easily be applied to many early computers that existed long before the term "CPU" ever came into widespread usage....
 with 128 MB
Megabyte

Megabyte is a SI prefix-multiple of the unit byte for digital information computer storage or transmission and is equal to 106 bytes....
 of DRAM
Dram

Dram or DRAM may refer to:* Dram , an imperial unit of mass and volume* Armenian dram, a monetary unit* Dynamic random access memory* Database of Recorded American Music...
 with error detection and correction and 3 MB of 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....
. Each rover also has 256 MB of 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....
. To survive during all of the various mission phases, the rover's vital instruments must stay within a temperature of -40 °C to +40 °C (-40 °F to 104 °F). At night the rovers are heated by eight radioisotope heater units (RHU) which each continuously generate 1 W
WATT

WATT is a radio station broadcasting a News radio-Talk radio-Sports radio format. Licensed to Cadillac, Michigan, it first began broadcasting in 1945....
 of thermal energy from the decay of radioisotopes, along with electrical heaters that operate only when necessary. A sputtered gold
Gold

Gold is a chemical element with the symbol Au and atomic number 79. It is a highly sought-after precious metal, having been used as money, as a store of value, in jewelry, in sculpture, and for ornamentation since the beginning of recorded history....
 film and a layer of silica aerogel
Aerogel

Aerogel is a low-density solid material derived from gel in which the liquid component of the gel has been replaced with gas. The result is an extremely low density solid with several remarkable properties, most notably its effectiveness as a thermal conductivity....
 are used for insulation.

Communication

The rover has a low-gain
Low-gain antenna

The low-gain antenna is an antenna with a broad radiowave beam width. This very wide beam allows for a more reliable signal that is best used in mountainous regions, where the signal will propagate reasonably well regardless of terrain....
 and a high-gain antenna
High-gain antenna

The high-gain antenna is an antenna with a focused, narrow radiowave beam width. This narrow beam width allows more precise targeting of the radio signal - also known as a directional antenna....
. The low-gain antenna is omnidirectional
Omnidirectional antenna

An omnidirectional antenna is an antenna system which radiates power uniformly in one plane with a directive pattern shape in a perpendicular plane....
, and transmits data at a low rate to Deep Space Network
Deep Space Network

The Deep Space Network, or DSN, is an international Wiktionary:network of communication facilities that supports interplanetary spacecraft missions, and radio astronomy and radar astronomy observations for the exploration of the solar system and the universe....
 (DSN) antennas on Earth. The high-gain antenna is directional and steerable, and can transmit data to Earth at a higher rate.

The rovers also use the low-gain antennas to communicate with spacecraft orbiting Mars, the Mars Odyssey and (before its failure) the Mars Global Surveyor
Mars Global Surveyor

The Mars Global Surveyor was a US spacecraft developed by NASA's Jet Propulsion Laboratory and launched November 1996. It began the United States's return to Mars after a 20-year absence....
. The orbiters relay data from and to Earth; most data to Earth is relayed through Odyssey. The benefits of using the orbiters are that they are closer to the rovers than the antennas on Earth, and have view of Earth for much longer than the rovers. The orbiters communicate with the rovers using UHF antennas, which have shorter range than the low and high-gain antennas. One UHF antenna is on the rover and one is on a petal of the lander to aid in gaining information during the critical landing event.

The rovers have a total of 9 cameras, which produce 1024-pixel by 1024-pixel images at 12 bits per pixel, but most images are truncated to 8 bits per pixel. They are then compressed using ICER
ICER

ICER is a wavelet-based image compression file format used by the NASA Mars Rovers. ICER has both lossy and lossless compression modes.The Mars Exploration Rovers ?Spirit? and ?Opportunity? both use ICER....
 before being stored and sent to Earth. Navigation, thumbnail, and many other image types are compressed to approximately 1 bit/pixel. Lower bit rates (less than 0.5 bit/pixel) are used for certain wavelengths of multi-color panoramic images.

ICER is based on wavelets, and was designed specifically for deep-space applications. It produces progressive compression, both lossless and lossy, and incorporates an error-containment scheme to limit the effects of data loss on the deep-space channel. It outperforms the lossy JPEG image compressor and the lossless Rice compressor used by the MPF mission.

Scientific instrumentation

Mer Panoramic Camera Pia05187
Sleepy Hollow Thermal
Mer Apxs Pia05113
The rover has various instruments. Three are mounted on one assembly:
  • Panoramic Camera (Pancam), for determining the texture, color, 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 structure of the local terrain.
  • Navigation Camera (Navcam), that has higher field of view but lower resolution and is monochromatic, for navigation and driving.
  • A mirror for the Miniature Thermal Emission Spectrometer
    Spectrometer

    A spectrograph is an optical instrument used to measure properties of light over a specific portion of the electromagnetic spectrum, typically used in spectroscopic analysis to identify materials....
     (Mini-TES), which identifies promising rocks and soils for closer examination, and determines the processes that formed them. It was built by Arizona State University
    Arizona State University

    Arizona State University is the largest public university research university in the United States under a single administration, with total student enrollment of 67,082 as of fall 2008....
    . See the main Mini-TES
    Mini-TES

    A Miniature Thermal Emission Spectrometer is an infrared spectrometer used for detecting the composition of a material from a distance. By making its measurements in the thermal infrared spectroscopy part of the electromagnetic spectrum, it has the ability to penetrate through the dust coatings common to the Martian surface which is usu...
     article.


The cameras are mounted 1.5 meters high on the Pancam Mast Assembly. One motor turns the assembly horizontally a whole revolution. Another points the cameras vertically, at most straight up or down. A third motor points the Mini-TES, up to 30° above the horizon and 50° below. The assembly was built by Ball Aerospace & Technologies Corp., Boulder, Colorado
Boulder, Colorado

Boulder is a Colorado municipalities#Home_Rule_Municipality that is the county seat and most populous city of Boulder County, Colorado, Colorado, in the United States....
, as was the High-Gain Antenna Gimbal (HGAG).

Four monochromatic hazard cameras (Hazcam
Hazcam

Hazcams are photographic cameras mounted on the front and rear of NASA's Spirit Rover and Opportunity Rover rover missions to Mars .The Hazcams are sensitive to visible light and return black and white images of 1024x1024 pixels....
s) are mounted on the rover's body, two in front and two behind.

The instrument deployment device (IDD), also called the rover arm, holds the following:
  • Mössbauer spectrometer (MB) MIMOS II, developed by Dr. Göstar Klingelhöfer at the Johannes Gutenberg
    Johannes Gutenberg

    Johannes Gensfleisch zur Laden zum Gutenberg was a Germany goldsmith and printer who is credited with being the first European to use movable type printing, in around 1439, and the global inventor of the mechanical printing press....
     University in Mainz
    Mainz

    Mainz is a city in Germany and the capital of the Germany States of Germany of Rhineland-Palatinate. It was a politically important seat of the Prince-elector of Mainz under the Holy Roman Empire, and previously was a Roman Empire fort city which commanded the west bank of the Rhine River and formed part of the northernmost frontier of th...
    , Germany
    Germany

    Germany , officially the Federal Republic of Germany , is a country in Central Europe. It is bordered to the north by the North Sea, Denmark, and the Baltic Sea; to the east by Poland and the Czech Republic; to the south by Austria and Switzerland; and to the west by France, Luxembourg, Belgium, and the Netherlands....
    , is used for close-up investigations of the mineralogy of iron-bearing rocks and soils.
  • Alpha Particle
    Alpha particle

    Alpha particles consist of two protons and two neutrons bound together into a particle identical to a helium atomic nucleus; hence, it can be written as He2+ or 42He2+....
     X-Ray
    X-ray

    X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 10 to 0.01 nanometers, corresponding to frequency in the range 30 Hertz to 30 Hertz and energies in the range 120 Electron volt to 120 keV....
     Spectrometer (APXS
    APXS

    An Alpha Particle X-Ray Spectrometer is a device that analyses the chemical element composition of a sample from the scattered alpha particles, emitted protons , and fluorescent X-rays after the sample is irradidated with alpha particles and X-rays from radioactive sources....
    ), developed by the Max Planck Institute for Chemistry
    Max Planck Institute for Chemistry

    The Max Planck Institute for Chemistry is a scientific research institute under the Max-Planck-Gesellschaft.Basic research in chemistry and related subjects is carried out at the four departments of the institute....
     in Mainz
    Mainz

    Mainz is a city in Germany and the capital of the Germany States of Germany of Rhineland-Palatinate. It was a politically important seat of the Prince-elector of Mainz under the Holy Roman Empire, and previously was a Roman Empire fort city which commanded the west bank of the Rhine River and formed part of the northernmost frontier of th...
    , Germany
    Germany

    Germany , officially the Federal Republic of Germany , is a country in Central Europe. It is bordered to the north by the North Sea, Denmark, and the Baltic Sea; to the east by Poland and the Czech Republic; to the south by Austria and Switzerland; and to the west by France, Luxembourg, Belgium, and the Netherlands....
    , is used for close-up analysis of the abundances of elements that make up rocks and soils.
  • Magnets, for collecting magnetic dust particles, developed by Jens Martin Knudsen
    Jens Martin Knudsen

    Jens Martin Knudsen was an internationally renowned Denmark astrophysicist, particularly well known in his home country.Born in Haurum near Aarhus, he was author or Co-authoring of more than 100 scientific articles, and a long time advisor to NASA....
    's group at the Niels Bohr Institute, Copenhagen
    Copenhagen

    Copenhagen is the capital and largest city of Denmark, with an urban area with a population of 1,153,615 . Copenhagen is situated on the Islands of Zealand and Amager....
    . The particles are analyzed by the Mössbauer Spectrometer and X-ray
    X-ray

    X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 10 to 0.01 nanometers, corresponding to frequency in the range 30 Hertz to 30 Hertz and energies in the range 120 Electron volt to 120 keV....
     Spectrometer to help determine the ratio of magnetic particles to non-magnetic particles and the composition of magnetic minerals in airborne dust and rocks that have been ground by the Rock Abrasion Tool. There are also magnets on the front of the rover, which are studied extensively by the Mössbauer spectrometer.
  • Microscopic Imager (MI) for obtaining close-up, high-resolution images of rocks and soils. Development was led by Ken Herkenhoff's team at the USGS Astrogeology Research Program
    Astrogeology Research Program

    The USGS Astrogeology Research Program has a rich history of participation in space exploration efforts and planetary mapping, starting in 1963 when the Flagstaff Science Center was established by Eugene Merle Shoemaker to provide lunar geologic mapping and assist in training astronauts destined for the Moon....
    .
  • Rock Abrasion Tool (RAT), developed by Honeybee Robotics, for removing dusty and weathered rock surfaces and exposing fresh material for examination by instruments on-board.


The robotic arm is able to place instruments directly up against rock and soil targets of interest.

Naming of Spirit and Opportunity

The Spirit and Opportunity rovers were named through a student essay competition. The winning entry was by Sofi Collis, a third-grade Russian-American student from Arizona.

I used to live in an orphanage. It was dark and cold and lonely. At night, I looked up at the sparkly sky and felt better. I dreamed I could fly there. In America, I can make all my dreams come true. Thank you for the 'Spirit' and the 'Opportunity.'
— Sofi Collis, age 9


Prior to this, during the development and building of the rovers, they were known as MER-1 (Opportunity) and MER-2 (Spirit). Internally NASA also uses the mission designations MER-A (Spirit) and MER-B (Opportunity) based on the order of landing on Mars (Spirit first then Opportunity).


SAP

The NASA team uses actual video game applications called SAP to view images collected from the rover, and to plan its daily activities. There is a version available to the public called Maestro
Maestro (software)

Maestro is a publicly-available version of the software used by the NASA Mars Exploration Rover team to view images collected from the rovers and plan the team's daily activities....
.

See also

  • 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....
  • Spirit rover
    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....
  • 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....
  • Atmospheric reentry
    Atmospheric reentry

    Atmospheric reentry refers to the movement of human-made or natural objects as they enter the atmosphere of a planet from outer space, in the case of Earth from an altitude above the "edge of space." This article primarily addresses the process of controlled reentry of vehicles which are intended to reach the planetary surface intact, but th...
  • Syd Lieberman, official storyteller of the Mars Exploration Mission
    Syd Lieberman

    Syd Lieberman is a noted American storyteller who has been telling stories professionally since 1982.He is a frequent performer at the National Storytelling Festival in Jonesborough, Tennessee....
  • Lunokhod programme
    Lunokhod programme

    Lunokhod 1 and 2 were a pair of Soviet Union robotic spacecraft lunar rover s landed on the Moon in 1970 and 1973, respectively. They were in operation conterminously with the Zond series of flyby missions....
     (Lunar rovers)
  • Mars Science Laboratory
    Mars Science Laboratory

    The Mars Science Laboratory is a NASA rover scheduled to be launched between October and December 2011 and perform the first-ever precision landing on Mars....
     (Next NASA Mars Rover)


Further reading

  • Roving Mars: Spirit, Opportunity, and the Exploration of the Red Planet by 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....
     (published August 2005; ISBN 1-4013-0149-5)
  • Postcards from Mars: The First Photographer on the Red Planet by Jim Bell
    Jim Bell

    James Dalton Bell is an American Crypto-anarchism who created the idea of arranging for anonymously-sponsored assassination payments via the Internet, which he called "Assassination market"....
     (published November 2006; ISBN 0-5259-4985-2)


External links


NASA

  • , a Java
    Java (programming language)

    Java is a programming language originally developed by James Gosling at Sun Microsystems and released in 1995 as a core component of Sun Microsystems' Java ....
     application for Mars/Earth time conversion


Instrumentation

  • , Cornell University
  • , Cornell University
  • , USGS Astrogeology Research Program
  • ("miniTES") , Arizona State University
  • , Johannes Gutenberg University
  • , Honeybee Robotics


Other

  • - Scientific papers from the first phase of the Spirit mission
  • : Centralized resource for all publicly released rover technical details
  • (access to the MER scientific data set)