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List Of Extraterrestrial Volcanoes
This is a list of active, dormant, and extinct volcanoes located beyond planet Earth. They may be designated mons (mountain), patera (an irregular crater) or tholus (small mountain or hill) in accordance with the International Astronomical Union's rules for planetary nomenclature. Many of them are nameless. Io Io, a moon of the planet Jupiter, is the most volcanically active body in the Solar System. Its volcanoes are believed to eject sulfur and sulfur dioxide, as well as basaltic and ultramafic silicate lavas. Mars Mars has many shield volcanoes, including the largest known volcano of the Solar System, but they are all dormant if not extinct. Venus On Venus, volcanic features are very numerous and quite diverse, but, like on Mars, none are known to be currently active. These volcanoes range from several to several hundred kilometers in diameter; a majority of them are shield volcanoes. In addition, Venus has unusual types of volcanoes: pancake domes and scalloped margin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volcanoes
A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates are diverging or converging, and most are found underwater. For example, a mid-ocean ridge, such as the Mid-Atlantic Ridge, has volcanoes caused by divergent tectonic plates whereas the Pacific Ring of Fire has volcanoes caused by convergent tectonic plates. Volcanoes can also form where there is stretching and thinning of the crust's plates, such as in the East African Rift and the Wells Gray-Clearwater volcanic field and Rio Grande rift in North America. Volcanism away from plate boundaries has been postulated to arise from upwelling diapirs from the core–mantle boundary, deep in the Earth. This results in hotspot volcanism, of which the Hawaiian hotspot is an example. Volcanoes are usually not created where two tectonic plates slide pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pancake Dome
A pancake dome is an unusual type of lava dome found on the planet Venus. They are widely scattered on that planet and often form groups or clusters, though with smaller numbers of pancake domes in each group than is typical for the more common shield volcanos. They are commonly found near coronae and ''tesserae'' (large regions of highly deformed terrain, folded and fractured in two or three dimensions, believed to be unique to Venus) in the lowland plains. Pancake domes are between 10 and 100 times larger than volcanic domes formed on Earth. Description Pancake domes have a broad, flat profile similar to shield volcanoes and are thought to form from one large, slow eruption of viscous silica-rich lava. They usually have a central pit- or bowl-like feature similar to a volcanic crater, but it is thought that these pits form after the eruption as the lava cools and emits gas rather than being a vent from which the lava originated. The surface of pancake domes are covered with pat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury (planet)
Mercury is the smallest planet in the Solar System and the closest to the Sun. Its orbit around the Sun takes 87.97 Earth days, the shortest of all the Sun's planets. It is named after the Roman god ' ( Mercury), god of commerce, messenger of the gods, and mediator between gods and mortals, corresponding to the Greek god Hermes (). Like Venus, Mercury orbits the Sun within Earth's orbit as an inferior planet, and its apparent distance from the Sun as viewed from Earth never exceeds 28°. This proximity to the Sun means the planet can only be seen near the western horizon after sunset or the eastern horizon before sunrise, usually in twilight. At this time, it may appear as a bright star-like object, but is more difficult to observe than Venus. From Earth, the planet telescopically displays the complete range of phases, similar to Venus and the Moon, which recurs over its synodic period of approximately 116 days. The synodic proximity of Mercury to Earth makes Mercury most ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MESSENGER - BV Microsymposium49
''MESSENGER'' was a NASA robotic space probe that orbited the planet Mercury between 2011 and 2015, studying Mercury's chemical composition, geology, and magnetic field. The name is a backronym for "Mercury Surface, Space Environment, Geochemistry, and Ranging", and a reference to the messenger god Mercury from Roman mythology. ''MESSENGER'' was launched aboard a Delta II rocket in August 2004. Its path involved a complex series of flybys – the spacecraft flew by Earth once, Venus twice, and Mercury itself three times, allowing it to decelerate relative to Mercury using minimal fuel. During its first flyby of Mercury in January 2008, ''MESSENGER'' became the second mission, after Mariner 10 in 1975, to reach Mercury. ''MESSENGER'' entered orbit around Mercury on March 18, 2011, becoming the first spacecraft to do so. It successfully completed its primary mission in 2012. Following two mission extensions, the spacecraft used the last of its maneuvering propellant to deorbit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mons Hansteen
Mons Hansteen is a mountain on the Moon, also known as Hansteen Alpha (α), named after Christopher Hansteen. It is roughly triangular in shape and occupies an area about 30 km across on the western margin of Oceanus Procellarum, southeast of the crater Hansteen and north of the dark-floored crater Billy. It is thought to be an extrusion of volcanic material that is younger than the crater Hansteen, with most of surface volcanic ash been deposited 3.5-3.74 billion years ago. The Mons Hansteen belongs to rare class of non-mare moon volcanoes. Composition The extruded material is significantly enriched in silica, and strongly depleted in iron and titanium oxides compared to surrounding mare terrain. Initially, it was believed its lavas are not as evolved as in Compton–Belkovich Thorium Anomaly, but by 2004 the low thorium enrichment signal was attributed to small size of volcanic complex, making it composition compatible with highly processed silicic lavas. By 2013, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mons Rümker
Mons Rümker is an isolated volcanic formation that is located in the northwest part of the Moon's near side, at selenographic coordinates 40.8° N, 58.1° W. The feature forms a large, elevated mound in the northern part of the Oceanus Procellarum. The mound has a diameter of 70 kilometres, and climbs to a maximum elevation of about 1,300 metres above the surrounding plain. It was named after Karl L. C. Rümker. Mons Rümker has a concentration of 22 lunar domes—rounded bulges across the top, some of which contain a small craterlet at the peak. These are wide, circular features with a gentle slope rising in elevation a few hundred meters to the midpoint. Lunar domes are similar to shield volcanoes, and are the result of lava erupting from localized vents followed by relatively slow cooling. Mons Rümker is surrounded by a scarp that separates it from the adjacent mare. The plateau rises to an altitude of 900 m in the west, 1,100 m in the south and 650 m in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lunar Dome
A lunar dome is a type of shield volcano that is found on the surface of the Earth's Moon. They are typically formed by highly viscous, possibly silica-rich lava, erupting from localized vents followed by relatively slow cooling. Lunar domes are wide, rounded, circular features with a gentle slope rising in elevation a few hundred meters to the midpoint. They are typically 8–12 km in diameter, but can be up to 20 km across. Some of the domes contain a small craterlet at the peak. Some of the domes have been shown to consist of the same materials as the lunar maria. Thus they could be created by some mechanism that differs from the mare-forming flows. It is thought that these domes are formed from a smaller magma chamber that is closer to the surface than is the case for a mare. This results in a lower pressure, and so the lava flows more slowly. The magma wells up through a crack in the surface, but the flow eventually concentrates through one primary vent. This concen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rille
Rille (German for 'groove') is typically used to describe any of the long, narrow depressions in the surface of the Moon that resemble channels. The Latin term is ''rima'', plural ''rimae''. Typically, a rille can be several kilometers wide and hundreds of kilometers in length. However, the term has also been used loosely to describe similar structures on a number of planets in the Solar System, including Mars, Venus, and on a number of moons. All bear a structural resemblance to each other. Structures Three types of rille are found on the lunar surface: * Sinuous rilles meander in a curved path like a mature river, and are commonly thought to be the remains of collapsed lava tubes or extinct lava flows. They usually begin at an extinct volcano, then meander and sometimes split as they are followed across the surface. , 195 sinuous rilles have been identified on the Moon. Vallis Schröteri in Oceanus Procellarum is the largest sinuous rille, and Rima Hadley is the only one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyroclastic Rock
Pyroclastic rocks (derived from the el, πῦρ, links=no, meaning fire; and , meaning broken) are clastic rocks composed of rock fragments produced and ejected by explosive volcanic eruptions. The individual rock fragments are known as pyroclasts. Pyroclastic rocks are a type of volcaniclastic deposit, which are deposits made predominantly of volcanic particles. 'Phreatic' pyroclastic deposits are a variety of pyroclastic rock that forms from volcanic steam explosions and they are entirely made of accidental clasts. 'Phreatomagmatic' pyroclastic deposits are formed from explosive interaction of magma with groundwater. Unconsolidated accumulations of pyroclasts are described as tephra. Tephra may become lithified to a pyroclastic rock by cementation or chemical reactions as the result of the passage of hot gases (fumarolic alteration) or groundwater (e.g. hydrothermal alteration and diagenesis) and burial, or, if it is emplaced at temperatures so hot that the soft glassy pyrocl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lunar Dome
A lunar dome is a type of shield volcano that is found on the surface of the Earth's Moon. They are typically formed by highly viscous, possibly silica-rich lava, erupting from localized vents followed by relatively slow cooling. Lunar domes are wide, rounded, circular features with a gentle slope rising in elevation a few hundred meters to the midpoint. They are typically 8–12 km in diameter, but can be up to 20 km across. Some of the domes contain a small craterlet at the peak. Some of the domes have been shown to consist of the same materials as the lunar maria. Thus they could be created by some mechanism that differs from the mare-forming flows. It is thought that these domes are formed from a smaller magma chamber that is closer to the surface than is the case for a mare. This results in a lower pressure, and so the lava flows more slowly. The magma wells up through a crack in the surface, but the flow eventually concentrates through one primary vent. This concen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shield Volcano
A shield volcano is a type of volcano named for its low profile, resembling a warrior's shield lying on the ground. It is formed by the eruption of highly fluid (low viscosity) lava, which travels farther and forms thinner flows than the more viscous lava erupted from a stratovolcano. Repeated eruptions result in the steady accumulation of broad sheets of lava, building up the shield volcano's distinctive form. Shield volcanoes are found wherever fluid low-silica lava reaches the surface of a rocky planet. However, they are most characteristic of ocean island volcanism associated with hot spots or with continental rift volcanism. They include the largest volcanoes on earth, such as Tamu Massif and Mauna Loa. Giant shield volcanoes are found on other planets of the Solar System, including Olympus Mons on Mars and Sapas Mons on Venus. Etymology The term 'shield volcano' is taken from the German term ''Schildvulkan'', coined by the Austrian geologist Eduard Suess in 1888 an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lunar Maria
The lunar maria (; singular: mare ) are large, dark, basaltic plains on Earth's Moon, formed by ancient asteroid impacts on the far side on the Moon that triggered volcanic activity on the opposite (near) side. They were dubbed , Latin for 'seas', by early astronomers who mistook them for actual seas. They are less reflective than the "highlands" as a result of their iron-rich composition, and hence appear dark to the naked eye. The maria cover about 16% of the lunar surface, mostly on the side visible from Earth. The few maria on the far side are much smaller, residing mostly in very large craters. The traditional nomenclature for the Moon also includes one (ocean), as well as features with the names ('lake'), ('marsh'), and ('bay'). The last three are smaller than maria, but have the same nature and characteristics. The names of maria refer to sea features (Mare Humorum, Mare Imbrium, Mare Insularum, Mare Nubium, Mare Spumans, Mare Undarum, Mare Vaporum, Oceanus Procellarum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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