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Thermal Emission Spectrometer
The Thermal Emission Spectrometer (TES) is an instrument on board Mars Global Surveyor. TES collects two types of data, hyperspectral thermal infrared data from 6 to 50 micrometres (μm) and bolometric visible-NIR (0.3 to 2.9 μm) measurements. TES has six detectors arranged in a 2x3 array, and each detector has a field of view of approximately 3 × 6 km on the surface of Mars. The TES instrument uses the natural harmonic vibrations of the chemical bonds in materials to determine the composition of gases, liquids, and solids. TES identified a large (30,000 square-kilometer) area that contained the mineral olivine. Olivine was found in the Nili Fossae formation. It is thought that the ancient impact that created the Isidis basin resulted in faults that exposed the olivine. Olivine is present in many mafic volcanic rocks. In the presence of water it weathers into minerals such as goethite, chlorite, smectite, maghemite, and hematite. Olivine was also discovered in many oth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mars Global Surveyor
''Mars Global Surveyor'' (MGS) was an American robotic space probe developed by NASA's Jet Propulsion Laboratory and launched November 1996. MGS was a global mapping mission that examined the entire planet, from the ionosphere down through the atmosphere to the surface. As part of the larger Mars Exploration Program, Mars Global Surveyor performed atmospheric monitoring for sister orbiters during aerobraking, and helped Mars rovers and lander missions by identifying potential landing sites and relaying surface telemetry. It completed its primary mission in January 2001 and was in its third extended mission phase when, on 2 November 2006, the spacecraft failed to respond to messages and commands. A faint signal was detected three days later which indicated that it had gone into safe mode. Attempts to recontact the spacecraft and resolve the problem failed, and NASA officially ended the mission in January 2007. MGS remains in a stable near-polar circular orbit at about 450 km ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hematite
Hematite (), also spelled as haematite, is a common iron oxide compound with the formula, Fe2O3 and is widely found in rocks and soils. Hematite crystals belong to the rhombohedral lattice system which is designated the alpha polymorph of . It has the same crystal structure as corundum () and ilmenite (). With this it forms a complete solid solution at temperatures above . Hematite naturally occurs in black to steel or silver-gray, brown to reddish-brown, or red colors. It is mined as an important ore mineral of iron. It is electrically conductive. Hematite varieties include ''kidney ore'', ''martite'' (pseudomorphs after magnetite), ''iron rose'' and ''specularite'' (specular hematite). While these forms vary, they all have a rust-red streak. Hematite is not only harder than pure iron, but also much more brittle. Maghemite is a polymorph of hematite (γ-) with the same chemical formula, but with a spinel structure like magnetite. Large deposits of hematite are found in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spectrometers
A spectrometer () is a scientific instrument used to separate and measure spectral components of a physical phenomenon. Spectrometer is a broad term often used to describe instruments that measure a continuous variable of a phenomenon where the spectral components are somehow mixed. In visible light a spectrometer can separate white light and measure individual narrow bands of color, called a spectrum. A mass spectrometer measures the spectrum of the masses of the atoms or molecules present in a gas. The first spectrometers were used to split light into an array of separate colors. Spectrometers were developed in early studies of physics, astronomy, and chemistry. The capability of spectroscopy to determine chemical composition drove its advancement and continues to be one of its primary uses. Spectrometers are used in astronomy to analyze the chemical composition of stars and planets, and spectrometers gather data on the origin of the universe. Examples of spectrometers are d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phil Christensen
Philip Russel Christensen (born 1953) is a geologist whose research interests focus on the composition, physical properties, processes, and morphology of planetary surfaces, with an emphasis on Mars and the Earth. He is currently a Regents' Professor and the Ed and Helen Korrick Professor of Geological Sciences at Arizona State University (ASU). Education Christensen earned his B.S. degree in Geology from the University of California, Los Angeles in 1976. He earned his M.S. in 1978 and his Ph.D. in 1981 in Geophysics and Space physics, both from the University of California, Los Angeles. Career Along with serving on the faculty of the Department of Geology at Arizona State University since 1981, Christensen is the principal investigator for the Mars Global Surveyor Thermal Emission Spectrometer (TES), the Mars Odyssey THEMIS, the Europa Clipper Europa Thermal Emission Imaging System and the Lucy Thermal Emission Spectrometer instruments, as well as a co-investigator for the Mars ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Infrared Spectroscopy
Thermal infrared spectroscopy (TIR spectroscopy) is the subset of infrared spectroscopy that deals with radiation emitted in the infrared part of the electromagnetic spectrum. The emitted infrared radiation, though similar to blackbody radiation, is different in that the radiation is banded at characteristic vibrations in the material. The method measures the thermal infrared radiation emitted (as opposed to being transmitted or reflected) from a volume or surface. This method is commonly used to identify the composition of surface by analyzing its spectrum and comparing it to previously measured materials. It is particularly suited to airborne and spaceborne applications. Thermal infrared spectrometers Airborne *TIMS: a multispectral radiometer flown on C-130, ER-2, and the Stennis Learjet aircraft. *SEBASS: a hyperspectral sensor developed and operated by The Aerospace Corporation. *Hyper-Cam: a hyperspectral thermal infrared camera developed by Telops. *OWL: a hyperspectr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Emission Imaging System
The Thermal Emission Imaging System (THEMIS) is a camera on board the 2001 Mars Odyssey orbiter. It images Mars in the visible and infrared parts of the electromagnetic spectrum in order to determine the thermal properties of the surface and to refine the distribution of minerals on the surface of Mars as determined by the Thermal Emission Spectrometer (TES). Additionally, it helps scientists to understand how the mineralogy of Mars relates to its landforms, and it can be used to search for thermal hotspots in the Martian subsurface. THEMIS is managed from the Mars Space Flight Facility at Arizona State University and was built by the Santa Barbara Remote Sensing division of Raytheon Technologies Corporation, an American multinational conglomerate headquartered in Waltham, Massachusetts. The instrument is named after Themis, the goddess of justice in ancient Greek mythology. Infrared camera THEMIS detects thermal infrared energy emitted by the Martian surface at nine di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meteorites
A meteorite is a solid piece of debris from an object, such as a comet, asteroid, or meteoroid, that originates in outer space and survives its passage through the atmosphere to reach the surface of a planet or moon. When the original object enters the atmosphere, various factors such as friction, pressure, and chemical interactions with the atmospheric gases cause it to heat up and radiate energy. It then becomes a meteor and forms a fireball, also known as a shooting star; astronomers call the brightest examples " bolides". Once it settles on the larger body's surface, the meteor becomes a meteorite. Meteorites vary greatly in size. For geologists, a bolide is a meteorite large enough to create an impact crater. Meteorites that are recovered after being observed as they transit the atmosphere and impact the Earth are called meteorite falls. All others are known as meteorite finds. Meteorites have traditionally been divided into three broad categories: stony meteorites that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chassigny (meteorite)
Chassigny is a Martian meteorite which fell on October 3, 1815, at approximately 8:00 am, in Chassigny, north-eastern France.Pistollet (1816) The circumstances of the Chassigny meteorite shower. Ann. Chim. Phys. (Paris) v. 1, pg 45-48. Chassigny is the meteorite for which the chassignites are named, and gives rise to the "C" in the name of the SNC group of meteorites. Chassigny is an olivine cumulate rock (dunite). It consists almost entirely of olivine with intercumulus pyroxene, feldspar Feldspars are a group of rock-forming aluminium tectosilicate minerals, also containing other cations such as sodium, calcium, potassium, or barium. The most common members of the feldspar group are the ''plagioclase'' (sodium-calcium) feldsp ..., and oxides. It was the only known chassignite until NWA2737 was found in the Moroccan Sahara in northwest Africa. Chassigny is particularly important because, unlike most SNCs, its noble gas composition differs from that in the current Atmospher ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nakhlite
Nakhlites are a group of Martian meteorites, named after the first one, Nakhla meteorite. Nakhlites are igneous rocks that are rich in augite and were formed from basaltic magma about 1.3 billion years ago. They contain augite and olivine crystals. Their crystallization ages, compared to a crater count chronology of different regions on Mars, suggest the nakhlites formed on the large volcanic construct of either Tharsis, Elysium, or Syrtis Major Planum.Treiman, A.H."The nakhlite meteorites: Augite-rich igneous rocks from Mars"- (PDF) Chemie der Erde 65, p. 203-270, (2005). URL accessed July 30, 2011. History A 2017 study dated them to at least four different eruptions from 1416 ± 7 Ma to 1322 ± 10 Ma. It has been shown that the nakhlites were suffused with liquid water around 620 million years ago and that they were ejected from Mars around 10.75 million years ago by an asteroid impact. They fell to Earth within the last 10,000 years. Possible source crater in E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shergottite
A Martian meteorite is a rock that formed on Mars, was ejected from the planet by an impact event, and traversed interplanetary space before landing on Earth as a meteorite. , 277 meteorites had been classified as Martian, less than half a percent of the 72,000 meteorites that have been classified. The largest complete, uncut Martian meteorite, Taoudenni 002, was recovered in Mali in early 2021. It weighs 14.5 kilograms (32 pounds) and is on display at the Maine Mineral & Gem Museum. There are three groups of Martian meteorite: shergottites, nakhlites and chassignites, collectively known as SNC meteorites. Several other Martian meteorites are ungrouped. These meteorites are interpreted as Martian because they have elemental and isotopic compositions that are similar to rocks and atmospheric gases on Mars, which have been measured by orbiting spacecraft, surface landers and rovers. The term does not include meteorites found on Mars, such as Heat Shield Rock. History By t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Martian Meteorite
A Martian meteorite is a rock that formed on Mars, was ejected from the planet by an impact event, and traversed interplanetary space before landing on Earth as a meteorite. , 277 meteorites had been classified as Martian, less than half a percent of the 72,000 meteorites that have been classified. The largest complete, uncut Martian meteorite, Taoudenni 002, was recovered in Mali in early 2021. It weighs 14.5 kilograms (32 pounds) and is on display at the Maine Mineral & Gem Museum. There are three groups of Martian meteorite: shergottites, nakhlites and chassignites, collectively known as SNC meteorites. Several other Martian meteorites are ungrouped. These meteorites are interpreted as Martian because they have elemental and isotopic compositions that are similar to rocks and atmospheric gases on Mars, which have been measured by orbiting spacecraft, surface landers and rovers. The term does not include meteorites found on Mars, such as Heat Shield Rock. History By t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maghemite
Maghemite (Fe2O3, γ-Fe2O3) is a member of the family of iron oxides. It has the same spinel ferrite structure as magnetite and is also ferrimagnetic. It is sometimes spelled as "maghaemite". ''Maghemite'' can be considered as an Fe(II)-deficient magnetite with formula \left(\ce\right)_A\left ce\rightB\ce where \square represents a vacancy, A indicates tetrahedral and B octahedral positioning. Occurrence Maghemite forms by weathering or low-temperature oxidation of spinels containing iron(II) such as magnetite or titanomagnetite. Maghemite can also form through dehydration and transformation of certain iron oxyhydroxide minerals, such as lepidocrocite and ferrihydrite. It occurs as widespread brown or yellow pigment in terrestrial sediments and soils. It is associated with magnetite, ilmenite, anatase, pyrite, marcasite, lepidocrocite and goethite. It is known to also form in areas that have been subjected to bushfires (particularly in the Leonora area of Western Australia) m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
