NASA's Mars Exploration Rover (MER) mission was a robotic space mission involving two Mars rovers, Spirit and Opportunity, exploring the planet Mars. It began in 2003 with the launch of the two rovers to explore the Martian surface and geology; both landed on Mars at separate locations in January 2004. Both rovers far outlived their planned missions of 90 Martian solar days: MER-A Spirit was active until March 22, 2010, while MER-B Opportunity was active until June 10, 2018.
Victoria is an impact crater on Mars located at 2.05°S, 5.50°W in the Meridiani Planum extraterrestrial plain, lying situated within the Margaritifer Sinus quadrangle (MC-19) region of the planet Mars. This crater was first visited by the Mars Exploration Rover Opportunity. It is roughly 800 metres (2,600 ft) wide, nearly eight times the size of the crater Endurance, visited by Opportunity from sols 951 to 1630. It is informally named after Victoria – one of the five Spanish ships of Ferdinand Magellan and the first ship to circumnavigate the globe – and formally named after Victoria, Seychelles. Along the edges of the crater are many outcrops within recessed alcoves and promontories, named for bays and capes that Magellan discovered.
Cydonia is a region on the planet Mars that has attracted both scientific and popular interest. The name originally referred to the albedo feature that was visible from earthbound telescopes. The area borders the plains of Acidalia Planitia and the highlands of Arabia Terra. The region includes the named features Cydonia Mensae, an area of flat-topped mesa-like features; Cydonia Colles, a region of small hills or knobs; and Cydonia Labyrinthus, a complex of intersecting valleys. As with other albedo features on Mars, the name Cydonia was drawn from classical antiquity, in this case from Kydonia, a historic polis on the island of Crete. Cydonia contains the "Face on Mars", located about halfway between the craters Arandas and Bamberg.
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 geology of Mars is the scientific study of the surface, crust, and interior of the planet Mars. It emphasizes the composition, structure, history, and physical processes that shape the planet. It is analogous to the field of terrestrial geology. In planetary science, the term geology is used in its broadest sense to mean the study of the solid parts of planets and moons. The term incorporates aspects of geophysics, geochemistry, mineralogy, geodesy, and cartography. A neologism, areology, from the Greek word Arēs (Mars), sometimes appears as a synonym for Mars's geology in the popular media and works of science fiction. The term areology is also used by the Areological Society.
The geology of solar terrestrial planets mainly deals with the geological aspects of the four terrestrial planets of the Solar System – Mercury, Venus, Earth, and Mars – and one terrestrial dwarf planet: Ceres. Earth is the only terrestrial planet known to have an active hydrosphere.
Dinorwic is a Martian impact crater, approximately 51 kilometers in diameter. It is named after the town in Ontario, Canada. Its name was approved by the International Astronomical Union in 1991. According to a surface age map of Mars based on US Geological Survey data, the area around Dinorwic is from the Noachian epoch, which places the area's age at 3.8 to 3.5 billion years ago. At the crater's rim, it is about 7,600 meters above zero altitude, and it is about 5,950 meters above zero altitude at its floor, giving it a depth of 1.6 kilometers.
Tugaske is a Martian impact crater, approximately 31 kilometres (19 mi) in diameter. It is located at 32.1°S, 101.2°W, south of the crater Dinorwic and southeast of the crater Virrat. It is named after a town in Saskatchewan, Canada, and its name was approved by the International Astronomical Union in 1991. According to a surface age map of Mars based on US Geological Survey data, the area around Tugaske is from the Noachian epoch, which places the area's age at 3.8 to 3.5 billion years ago. The elevation around the rim averages about 6,700 metres (22,000 ft) above zero altitude, and the deepest part of the crater floor, in the central pit, measures 5,100 metres (16,700 ft) above zero altitude. The crater is therefore about 1.6 kilometres (0.99 mi) deep.
Koga is an impact crater on Mars, approximately 19 kilometers in diameter. It is located at 29.3°S, 103.8°W, north of the crater Virrat and northeast of the crater Dinorwic. To the north is the crater Nhill. It is named after a town in Tanzania, and its name was approved by the International Astronomical Union in 1991. According to a surface age map of Mars based on US Geological Survey data, the area around Koga is from the Noachian epoch, which places the area's age at 3.8 to 3.5 billion years ago. Sharp blocks and cliffs poke through a mantle of fine material located at the bottom of the crater. At the deepest part of the crater, it is about 5,200 meters in elevation above zero altitude, and its rim averages about 6,400 meters above zero altitude. It is therefore approximately 1.2 kilometers deep.
Srīpur is a Martian impact crater, approximately 22.99 kilometres (14.29 mi) in diameter. It is located at -31.1°S, 100.8°W, southeast of the crater Dinorwic and northeast of the crater Tugaske. It is named for Sripur, a town in Bangladesh, and its name was adopted by the International Astronomical Union in 1991.
Gale is a crater, and probable dry lake, at 5.4°S 137.8°E in the northwestern part of the Aeolis quadrangle on Mars. It is 154 km (96 mi) in diameter and estimated to be about 3.5–3.8 billion years old. The crater was named after Walter Frederick Gale, an amateur astronomer from Sydney, Australia, who observed Mars in the late 19th century. Aeolis Mons is a mountain in the center of Gale and rises 5.5 km (18,000 ft) high. Aeolis Palus is the plain between the northern wall of Gale and the northern foothills of Aeolis Mons. Peace Vallis, a nearby outflow channel, 'flows' down from the hills to the Aeolis Palus below and seems to have been carved by flowing water. Several lines of evidence suggest that a lake existed inside Gale shortly after the formation of the crater.
Mars is the fourth planet and the furthest terrestrial planet from the Sun. The reddish color of its surface is due to finely grained iron(III) oxide dust in the soil, giving it the nickname "the Red Planet". Mars has a second smallest radius among the planets in the Solar System at 3,389.5 km (2,106 mi) and has a surface gravity of 3.72 m/s2 (12.2 ft/s2), which is 38% of Earth's gravity. The Martian dichotomy can be clearly seen on the surface: on average, the terrain on Mars northern hemisphere is flatter and lower than Mars southern hemisphere. Mars has a very thin atmosphere made primarily of carbon dioxide and two irregularly shaped natural satellites: Phobos and Deimos.
Licancabur Lake is a crater lake in Chile located on the volcano Licancabur. It is close to the city San Pedro de Atacama and also very close to the border of Chile with Bolivia.
Almost all water on Mars today exists as ice, though it also exists in small quantities as vapor in the atmosphere. What was thought to be low-volume liquid brines in shallow Martian soil, also called recurrent slope lineae, may be grains of flowing sand and dust slipping downhill to make dark streaks. The only place where water ice is visible at the surface is at the north polar ice cap. Abundant water ice is also present beneath the permanent carbon dioxide ice cap at the Martian south pole and in the shallow subsurface at more temperate conditions. More than 5 million km3 of ice have been detected at or near the surface of Mars, enough to cover the whole planet to a depth of 35 meters (115 ft). Even more ice is likely to be locked away in the deep subsurface.
Endeavour is an impact crater located in the Meridiani Planum extraterrestrial plain within the Margaritifer Sinus quadrangle (MC-19) region of the planet Mars. Endeavour is about 22 kilometers (14 mi) in diameter. Using Mars Reconnaissance Orbiter data, phyllosilicate-bearing outcrops have been detected along its rim. These minerals may have formed under wet conditions in a low-acidic environment during the early history of Mars. There are raised rim segments to the north, east, and southwest. The rim has become worn, rounded and degraded, with infilling of plains material in a manner similar to the Victoria crater.
Mount Sharp, officially Aeolis Mons, is a mountain on Mars. It forms the central peak within Gale crater and is located around 5.08°S 137.85°E, rising 5.5 km (18,000 ft) high from the valley floor. Its ID in the United States Geological Survey's Gazetteer of Planetary Nomenclature is 15000.
Peace Vallis is an ancient stream valley on the northern rim of Gale Crater on the planet Mars. It is notable for its associated alluvial fan which lies near the Mars Science Laboratory Curiosity landing site. The valley and alluvial fan provide evidence for geologically recent (Amazonian-aged) fluvial activity and sustained water flow on Mars. Recent high-resolution orbital images of Peace Vallis and its watershed also suggest that at least one glacial episode affected Gale crater. All of this evidence has implications for the history of water on Mars and the planet's long-term habitability. Understanding Peace Vallis and its fan also provides geologic context for the rocks observed on the ground by the Curiosity rover.
Opportunity is a robotic rover that was active on the planet Mars from 2004 to 2018. Launched on July 7, 2003, Opportunity landed on Mars' Meridiani Planum on January 25, 2004, at 05:05 Ground UTC, three weeks after its twin Spirit (MER-A), also part of NASA's Mars Exploration Rover Mission, touched down on the other side of the planet. While Spirit became immobile in 2009 and ceased communications in 2010, Opportunity exceeded its planned 90 sol duration of activity by 14 years 46 days. Opportunity continued to move, gather scientific observations, and report back to Earth until 2018. What follows is a summary of events during its continuing mission.
Very is a crater on Mars, located south of the planet's equator in the heavily cratered highlands of Terra Sirenum in the Phaethontis quadrangle at 49.2°S and 177.1°W. It measures approximately 114.81 kilometres (71.34 mi) in diameter. The crater was named after American astronomer Frank Washington Very.
In modern times, numerous impact events on Mars have been detected. Although most have been inferred from the appearance of new impact craters on the planet, some have corresponded to marsquakes felt by the InSight lander. To date, no impacting meteors have been directly observed as a fireball or discovered in space before impact.
