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.
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. As of September 2020, 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 and is on display at the Maine Mineral & Gem Museum.
The Meridiani Planum (alternately Meridiani plain, Meridiani plains, Terra Meridiani, or Terra Meridiani plains) is either a large plain straddling the equator of Mars and covered with a vast number of spherules containing a lot of iron oxide or a region centered on this plain that includes some adjoining land. The plain sits on top of an enormous body of sediments that contains a lot of bound water. The iron oxide in the spherules is crystalline (grey) hematite (Fe203).
Heat Shield Rock is a basketball-sized iron-nickel meteorite found on the Meridiani Planum plain of Mars by the Mars rover Opportunity in January 2005.
Elysium Mons is a volcano on Mars located in the volcanic province Elysium, at 25.02°N 147.21°E, in the Martian eastern hemisphere. It stands about 12.6 km (41,000 ft) above its base, and about 14.1 km (46,000 ft) above the Martian datum, making it the third tallest Martian mountain in terms of relief and the fourth highest in elevation. Its diameter is about 240 km (150 mi), with a summit caldera about 14 km (8.7 mi) across. It is flanked by the smaller volcanoes Hecates Tholus to the northeast, and Albor Tholus to the southeast.
The Shergotty meteorite is the first example of the shergottite Martian meteorite family. It was a 5-kilogram (11 lb) meteorite which fell to Earth at Sherghati, in the Gaya district, Bihar, India on 25 August 1865, and was retrieved by witnesses almost immediately. Radiometric dating indicates that it solidified from a volcanic magma about 4.1 billion years ago. It is composed mostly of pyroxene and is thought to have undergone preterrestrial aqueous alteration for several centuries. Certain features within its interior are suggestive of being remnants of biofilm and their associated microbial communities.
Tooting is an impact crater with volcanic features at 23.1°N, 207.1°E, in Amazonis Planitia, due west of the volcano Olympus Mons, on Mars. It was identified by planetary geologist Peter Mouginis-Mark in September 2004. Scientists estimate that its age is on the order of hundreds of thousands of years, which is relatively young for a Martian crater. A later study confirms this order of magnitude estimate. A preliminary paper describing the geology and geometry of Tooting was published in 2007 by the journal Meteoritics and Planetary Science, vol. 42, pages 1615–1625. Further papers have been published, including a 2010 analysis of flows on the walls of Tooting crater by A. R. Morris et al., and a 2012 review paper by P.J. Mouginis-Mark and J.M. Boyce in Chemie der Erde Geochemistry, vol. 72, p. 1–23. A geologic map has also been submitted in 2012 to the U.S. Geological Survey for consideration and future publication.
Lomonosov is a crater on Mars, with a diameter close to 150 km. It is located in the Martian northern plains. Since it is large and found close to the boundary between the Mare Acidalium quadrangle and the Mare Boreum quadrangle, it is found on both maps. The topography is smooth and young in this area, hence Lomonosov is easy to spot on large maps of Mars.
Zunil is an impact crater near the Cerberus Fossae on Mars, with a diameter of 10.26 kilometres. It is named after the town of Zunil in Guatemala. The crater is located in the Elysium quadrangle. Visible in images from the Viking 1 and Viking 2 Mars orbiters in the 1970s, Zunil was subsequently imaged at higher resolution for the first time by the Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) in 2000.
Mojave is a 58 km diameter impact crater in the Oxia Palus quadrangle of Mars, located at 7.5° N and 33.0° W. It was named after the town of Mojave in southern California, U.S.
Mars may contain ores that would be very useful to potential colonists. The abundance of volcanic features together with widespread cratering are strong evidence for a variety of ores. While nothing may be found on Mars that would justify the high cost of transport to Earth, the more ores that future colonists can obtain from Mars, the easier it would be to build colonies there.
Nakhlites are a group of Martian meteorites, named after the first one, Nakhla meteorite.
The composition of Mars covers the branch of the geology of Mars that describes the make-up of the planet Mars.
The geological history of Mars follows the physical evolution of Mars as substantiated by observations, indirect and direct measurements, and various inference techniques. Methods dating back to 17th-century techniques developed by Nicholas Steno, including the so-called law of superposition and stratigraphy, used to estimate the geological histories of Earth and the Moon, are being actively applied to the data available from several Martian observational and measurement resources. These include landers, orbiting platforms, Earth-based observations, and Martian meteorites.
Northwest Africa 7034 is a Martian meteorite believed to be the second oldest yet discovered. It is estimated to be two billion years old and contains the most water of any Martian meteorite found on Earth. Although it is from Mars it does not fit into any of the three SNC meteorite categories, and forms a new Martian meteorite group named "Martian ". Nicknamed "Black Beauty", it was purchased in Morocco and a slice of it was donated to the University of New Mexico by its American owner. The image of the original NWA 7034 was photographed in 2012 by Carl Agee, University of New Mexico.
The Amazonian is a geologic system and time period on the planet Mars characterized by low rates of meteorite and asteroid impacts and by cold, hyperarid conditions broadly similar to those on Mars today. The transition from the preceding Hesperian period is somewhat poorly defined. The Amazonian is thought to have begun around 3 billion years ago, although error bars on this date are extremely large. The period is sometimes subdivided into the Early, Middle, and Late Amazonian. The Amazonian continues to the present day.
Burton is an impact crater in the Memnonia quadrangle of Mars. It is 123.0 km in diameter and was named after British astronomer Charles E. Burton; the name was approved in 1973.
Dampier is an impact crater in the Memnonia quadrangle of Mars. It was named after the town of Dampier, Western Australia, in 2021.
Khujirt is an impact crater in the Memnonia quadrangle of Mars. It was named after the district of Khujirt, central Mongolia, in 2021.
