An artist's concept of the Mars Observer in orbit around Mars. This mission would have been NASA's first spacecraft to Mars in two decades.

Mars Observer, launched by NASA in September 25, 1992, was the first of the proposed Observer series of planetary missions, and was designed to study the geoscience and climate of Mars. Contact with the spacecraft was lost three days before scheduled orbit insertion and was never re-established. Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... The National Aeronautics and Space Administration (NASA) is an agency of the United States federal government, responsible for the nations public space program. ... September 25 is the 268th day of the year (269th in leap years) in the Gregorian calendar. ... 1992 (MCMXCII) was a leap year starting on Wednesday. ... NASAs Planetary Observer series was still birthed, resulting in only one, failed, mission. ... Earth science (also known as geoscience or the geosciences), is an all-embracing term for the sciences related to the planet Earth. ... Mars is the fourth planet from the Sun in the solar system, named after the Roman god of war (the counterpart of the Greek Ares), on account of its blood red color as viewed in the night sky. ...

The primary science objectives for the mission were to:

1. determine the global elemental and mineralogical character of the surface material;
2. define globally the topography and gravitational field;
3. establish the nature of the Martian magnetic field;
4. determine the temporal and spatial distribution, abundance, sources, and sinks of volatiles and dust over a seasonal cycle;
5. explore the structure and circulation of the atmosphere.

The bus and electronics of the Observer series of spacecraft, used to study the terrestrial planets and near-Earth asteroids, were derived from the Satcom-K and DMSP/TIROS spacecraft. The rectangular bus section was 2.1 x 1.5 x 1.1 m. During the cruise phase of the mission, the high-gain antenna and the booms for the magnetometer (MAG/ER) and gamma-ray spectrometer (GRS) were partially deployed. When fully deployed, the two booms were each 6 m long. The 1.5 m diameter high-gain antenna was, when fully deployed, on a 5.5 m boom to allow for clearance over the solar array when the antenna was pointed toward Earth. This article is about Topography as the study of landforms at any scale. ... In physics, a magnetic field is an axial vector field that traces out solenoidal lines of force in and around closed electric circuits and bar magnets. ... Atmosphere is the general name for a layer of gases that may surround a material body of sufficient mass. ... The Space Shuttle Discovery as seen from the International Space Station. ... A magnetometer is a scientific instrument used to measure the strength and/or direction of the magnetic field in the vicinity of the instrument. ... Gamma rays or gamma-ray (denoted as γ) are forms of electromagnetic radiation (EMR) or light emissions of a specific frequency produced from sub-atomic particle interaction, such as electron-positron annihilation and radioactive decay; most are generated from nuclear reactions occurring within the interstellar medium of space. ...

Pointing control for the spacecraft was maintained through the use of four reaction wheels. Attitude information was provided by a horizon sensor (which defined the direction of the nadir when the spacecraft is in Martian orbit), a 6-slit star scanner (for inertial attitude), gyros and accelerometers (for measuring angular rates and linear accelerations), and five sun sensor heads tied into a single sun sensor electronics box. A momentum wheel is a type of flywheel used primarily by spacecraft to change their angular momentum without using fuel for rockets or other reaction devices. ... In the context of spacecraft, attitude control is control of the angular position and rotation of the spacecraft, either relative to the object that it is orbiting, or relative to the celestial sphere. ...

Mars Observer launch preparations

Power was provided through a six-panel solar array which, when fully deployed, measured 7.0 x 3.7 m. During the cruise phase, however, only four panels were deployed (due to the proximity of the spacecraft to the sun) to reduce the amount of power generated. During periods when the spacecraft was in Mars' shadow, energy was to be provided by two Ni-Cd batteries, each with a capacity of 43 ampere-hours. Image File history File links Size of this preview: 420 × 600 pixels Full resolution (700 × 1000 pixel, file size: 214 KB, MIME type: image/jpeg) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Mars Observer ... Image File history File links Size of this preview: 420 × 600 pixels Full resolution (700 × 1000 pixel, file size: 214 KB, MIME type: image/jpeg) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Mars Observer ... Solar Panel made by BP Solar The solar panels (photovoltaic arrays) on this small yacht at sea can charge the 12 V batteries at up to 9 Amps in full, direct sunlight. ... The nickel-cadmium battery (commonly abbreviated NiCd and pronounced nye-cad) is a popular type of rechargeable battery for portable electronics and toys using the metals nickel (Ni) and cadmium (Cd) as the active chemicals. ...

The interplanetary cruise phase of the mission was intended primarily for spacecraft and instrument checkout and calibration. Two periods of data collection for the MAG/ER and GRS and one for the gravity wave experiment were planned for this phase as well. During the four month period from Mars orbital insertion until the spacecraft was to achieve its final mapping orbit, only data collection for the MAG/ER, GRS, and Thermal Emission Spectrometer (TES) were scheduled. The mapping phase of the mission was scheduled to nominally last one Martian year. Mars Observer was also to support the acquisition of data from the Russian Mars 1994 mission through the use of the joint French-Russian-American Mars Balloon Relay instrument. The Thermal Emission Spectrometer is a type of passive spectrometer that can identify the composition of surfaces by analyzing its infrared spectrum. ... The Darian Calendar is a system of time-keeping designed to serve the needs of any possible future human settlers on the planet Mars. ...

Contact with Mars Observer was lost on August 21, 1993, three days before scheduled orbit insertion, for unknown reasons and has not been re-established. It is not known whether the spacecraft was able to follow its automatic programming and go into Mars orbit or if it flew by Mars and is now in a heliocentric orbit. It was speculated that there may have been an explosion in a propellant line during pressurisation procedures just before the orbital insertion engine burn. It is believed that hypergolic fuel may have leaked past valves in the system during cruise to Mars, allowing the fuel and oxidiser to combine prematurely before reaching the combustion chamber. The engine was derived from an Earth orbital satellite's and not really designed to lie dormant for many months before being fired. August 21 is the 233rd day of the year (234th in leap years) in the Gregorian calendar. ... Year 1993 (MCMXCIII) was a common year starting on Friday (link will display full 1993 Gregorian calendar). ... A heliocentric orbit is an orbit around the sun. ...

Although none of the primary objectives of the mission were achieved, cruise mode data were collected up to loss of contact. The total cost of the Mars Observer mission including development, construction, launch, and ground support is estimated at US$980 million. However, science instruments originally developed for Mars Observer are being used by three other orbiters, the Mars Global Surveyor, launched in 1996, Mars Odyssey, launched in 2001, and the Mars Reconnaissance Orbiter, launched in 2005. The Mars Global Surveyor (MGS) was a US spacecraft developed by NASA and the Jet Propulsion Laboratory and launched November 1996. ... 1996 (MCMXCVI) was a leap year starting on Monday of the Gregorian calendar, and was designated the International Year for the Eradication of Poverty. ... Artists concept of the 2001 Mars Odyssey Spacecraft 2001 Mars Odyssey is an unmanned spacecraft orbiting the planet Mars. ... Year 2001 (MMI) was a common year starting on Monday of the Gregorian calendar. ... NASAs Mars Reconnaissance Orbiter (MRO) is a multipurpose spacecraft designed to conduct reconnaissance and exploration of Mars from orbit. ...

See also

• Exploration of Mars
• Space exploration
• Unmanned space missions
• Planetary Observer program

Computer generated image of one of the two Mars Exploration Rovers which touched down on Mars in 2004. ... Space exploration is the physical exploration of outer space, both by human spaceflights and by robotic spacecraft. ... It has been suggested that Space probe be merged into this article or section. ... NASAs Planetary Observer series was still birthed, resulting in only one, failed, mission. ...

External links

• Mars Observer at NSSDC Master Catalog
• The Loss of Mars Observer at Malin Space Science Systems
• NASA Spacelink - Mars Observer

Coordinates: 28°33′43″N, 80°34′38″W Computer generated image of one of the two Mars Exploration Rovers which touched down on Mars in 2004. ... The eight planets and three dwarf planets of the Solar System. ... Adjectives: Martian Atmosphere Surface pressure: 0. ... The Marsnik program of unmanned spacecraft were the Soviet Unions first attempt at interplanetary exploration. ... Sputnik 22 (also known as Korabl 11 and Mars 1962A) was an attempted Mars flyby mission, presumably similar to the Mars 1 mission launched 8 days later. ... Mars 1 (1962 Beta Nu 1) was an automatic interplanetary station launched in the direction of Mars on November 1, 1962, the first of the Soviet Mars probe program, with the intent of flying by the planet at a distance of about 11,000 km. ... Sputnik 24 (also known as Beta Xi 1, Korabl 13, and Mars 1962B) was an attempted Mars lander mission. ... Mariner 3 and 4 were identical spacecraft of the Mariner program designed to carry out the first flybys of Mars. ... Mars 3MV-4A Zond 2, a member of the Soviet Zond program, was the second Soviet spacecraft to attempt a flyby of Mars. ... Mars 1969A, also known as Mars 69A in Soviet documentation, was one of two identical probes (the other being Mars 1969B), each consisting of an orbiter and an atmospheric probe. ... Mars 1969B, also known as Mars 69BA in Soviet documentation, was one of two identical probes (the other being Mars 1969A), each consisting of an orbiter and an atmospheric probe. ... Mariner 8. ... Cosmos 419 This launch was intended to be a Mars orbiting mission. ... The Mars program was a series of Mars unmanned landers and orbiters launched by the Soviet Union in the early 1970s. ... The Mars program was a series of Mars unmanned landers and orbiters launched by the Soviet Union in the early 1970s. ... The Phobos program was an unmanned space mission consisting of two probes launched by the Soviet Union to study Mars and its moons Phobos and Deimos. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... Nozomi at Mars Nozomi (のぞみ) (Japanese for Hope and known before launch as Planet-B) was planned as a Mars-orbiting aeronomy probe. ... Mars Climate Orbiter during tests The Mars Climate Orbiter (formerly the Mars Surveyor 98 Orbiter) was one of two spacecraft in the Mars Surveyor 98 program, the other being the Mars Polar Lander (formerly the Mars Surveyor 98 Lander). ... Conceptual drawing of the Mars Polar Lander on the surface of Mars. ... The Deep Space 2 mission, which launched in January 1999 as part of NASAs New Millennium Program, consisted of two highly advanced miniature probes to Mars. ... Beagle 2 as it would have looked on Mars Beagle 2 was an unsuccessful British landing spacecraft that formed part of the European Space Agencys 2003 Mars Express mission. ... The Voyager program was a planned series of unmanned NASA probes to Mars. ... Conceptual drawing Mars Surveyor 2001 Lander was a planned NASA Mars probe which was cancelled in May 2000 in the wake of the failures of the Mars Climate Orbiter and Mars Polar Lander missions in late 1999. ... For late 2007 (or 2009) CNES (French Space Agency) and ESA (European Space Agency) had planned to send to Mars remote sensing orbiter and four small Netlanders. ... Introduction NASA planned to establish a so-called interplanetary Internet with the launch of the Mars Telecommunications Orbiter in 2009. ... Map of Earth showing lines of latitude (horizontally) and longitude (vertically), Eckert VI projection; large version (pdf, 1. ...