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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] |
Carl Ludwig Christian Rümker
Carl Ludwig Christian Rümker (28 May 1788 – 21 December 1862) was a German astronomer. Early life (1788-1821) Rümker was born in Burg Stargard, in Mecklenburg, Germany, the son of J. F. Rümker, a court-councillor. He showed an aptitude for mathematics and studied at the Builders' Academy, Berlin, graduating in 1807 as a master builder. Instead of a career in building, he taught mathematics in Hamburg until 1809 when he went to England. Rümker served as a midshipman in the British East India Company and then in the British merchant navy from 1811 until 1813. In July 1813 he was seized by a pressgang and joined the Royal Navy. He served in the Royal Navy as a schoolmaster until 1817 on ''HMS Benbow'', ''Montague'' and ''Albion'' taking part in the expedition to Algiers in 1816 whilst on the ''Albion''. In 1817 he met Austrian astronomer Baron Franz Xaver von Zach, who influenced Rümker to study astronomy. Rümker was director of the school of navigation at Hamburg from 1819 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lava
Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or underwater, usually at temperatures from . The volcanic rock resulting from subsequent cooling is also often called ''lava''. A lava flow is an outpouring of lava during an effusive eruption. (An explosive eruption, by contrast, produces a mixture of volcanic ash and other fragments called tephra, not lava flows.) The viscosity of most lava is about that of ketchup, roughly 10,000 to 100,000 times that of water. Even so, lava can flow great distances before cooling causes it to solidify, because lava exposed to air quickly develops a solid crust that insulates the remaining liquid lava, helping to keep it hot and inviscid enough to continue flowing. The word ''lava'' comes from Italian and is probably derived from the Latin word ''labes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lava Domes
In volcanology, a lava dome is a circular mound-shaped protrusion resulting from the slow extrusion of viscous lava from a volcano. Dome-building eruptions are common, particularly in convergent plate boundary settings. Around 6% of eruptions on Earth are lava dome forming. The geochemistry of lava domes can vary from basalt (e.g. Semeru, 1946) to rhyolite (e.g. Chaiten, 2010) although the majority are of intermediate composition (such as Santiaguito, dacite-andesite, present day) The characteristic dome shape is attributed to high viscosity that prevents the lava from flowing very far. This high viscosity can be obtained in two ways: by high levels of silica in the magma, or by degassing of fluid magma. Since viscous basaltic and andesitic domes weather fast and easily break apart by further input of fluid lava, most of the preserved domes have high silica content and consist of rhyolite or dacite. Existence of lava domes has been suggested for some domed structures on the Mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shield Volcanoes
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 and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
