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Herschel (crater)
There are several impact craters named Herschel in the Solar System, although the best known is the huge crater on Saturn's moon Mimas. Most are named after the eighteenth-century astronomer William Herschel. *Herschel (lunar crater), on the Moon * Herschel (Martian crater), on Mars *Herschel (Mimantean crater), on Mimas * J. Herschel (crater) - a lunar crater named after John Herschel *C. Herschel (crater) C. Herschel is a small lunar impact crater that lies on the western part of Mare Imbrium. It is named after German astronomer Caroline Herschel. It is a circular, bowl-shaped formation that has not undergone significant erosion. The interior floo ... - a lunar crater named after Caroline Herschel {{Set index article, astronomical objects it:Herschel#Astronomia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Impact Crater
An impact crater is a circular depression in the surface of a solid astronomical object formed by the hypervelocity impact of a smaller object. In contrast to volcanic craters, which result from explosion or internal collapse, impact craters typically have raised rims and floors that are lower in elevation than the surrounding terrain. Lunar impact craters range from microscopic craters on lunar rocks returned by the Apollo Program and small, simple, bowl-shaped depressions in the lunar regolith to large, complex, multi-ringed impact basins. Meteor Crater is a well-known example of a small impact crater on Earth. Impact craters are the dominant geographic features on many solid Solar System objects including the Moon, Mercury, Callisto, Ganymede and most small moons and asteroids. On other planets and moons that experience more active surface geological processes, such as Earth, Venus, Europa, Io and Titan, visible impact craters are less common because they become eroded ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar System
The Solar SystemCapitalization of the name varies. The International Astronomical Union, the authoritative body regarding astronomical nomenclature, specifies capitalizing the names of all individual astronomical objects but uses mixed "Solar System" and "solar system" structures in theinaming guidelines document. The name is commonly rendered in lower case ('solar system'), as, for example, in the ''Oxford English Dictionary'' an''Merriam-Webster's 11th Collegiate Dictionary''. is the gravity, gravitationally bound system of the Sun and the objects that orbit it. It Formation and evolution of the Solar System, formed 4.6 billion years ago from the gravitational collapse of a giant interstellar molecular cloud. The solar mass, vast majority (99.86%) of the system's mass is in the Sun, with most of the Jupiter mass, remaining mass contained in the planet Jupiter. The four inner Solar System, inner system planets—Mercury (planet), Mercury, Venus, Earth and Mars—are terrest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saturn
Saturn is the sixth planet from the Sun and the second-largest in the Solar System, after Jupiter. It is a gas giant with an average radius of about nine and a half times that of Earth. It has only one-eighth the average density of Earth; however, with its larger volume, Saturn is over 95 times more massive. Saturn's interior is most likely composed of a core of iron–nickel and rock (silicon and oxygen compounds). Its core is surrounded by a deep layer of metallic hydrogen, an intermediate layer of liquid hydrogen and liquid helium, and finally, a gaseous outer layer. Saturn has a pale yellow hue due to ammonia crystals in its upper atmosphere. An electrical current within the metallic hydrogen layer is thought to give rise to Saturn's planetary magnetic field, which is weaker than Earth's, but which has a magnetic moment 580 times that of Earth due to Saturn's larger size. Saturn's magnetic field strength is around one-twentieth of Jupiter's. The outer atmosphere is g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mimas (moon)
Mimas , also designated Saturn I, is a moon of Saturn discovered in 1789 by William Herschel. It is named after Mimas, a son of Gaia in Greek mythology. With a diameter of , it is the smallest astronomical body that is known to still be rounded in shape because of self-gravitation. However, Mimas is not actually in hydrostatic equilibrium for its current rotation. Discovery Mimas was discovered by the astronomer William Herschel on 17 September 1789. He recorded his discovery as follows: "I continued my observations constantly, whenever the weather would permit; and the great light of the forty-feet speculum was now of so much use, that I also, on the 17th of September, detected the seventh satellite, when it was at its greatest preceding elongation." The 40-foot telescope was a metal mirror reflecting telescope built by Herschel, with a aperture. The 40 feet refers to the length of the focus, not the aperture diameter as more common with modern telescopes. Name Mima ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Herschel
Frederick William Herschel (; german: Friedrich Wilhelm Herschel; 15 November 1738 – 25 August 1822) was a German-born British astronomer and composer. He frequently collaborated with his younger sister and fellow astronomer Caroline Herschel (1750–1848). Born in the Electorate of Hanover, William Herschel followed his father into the military band of Hanover, before emigrating to Great Britain in 1757 at the age of nineteen. Herschel constructed his first large telescope in 1774, after which he spent nine years carrying out sky surveys to investigate double stars. Herschel published catalogues of nebulae in 1802 (2,500 objects) and in 1820 (5,000 objects). The resolving power of the Herschel telescopes revealed that many objects called nebulae in the Messier catalogue were actually clusters of stars. On 13 March 1781 while making observations he made note of a new object in the constellation of Gemini. This would, after several weeks of verification and consultation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Herschel (lunar Crater)
Herschel is a lunar impact crater located just to the north of the walled plain Ptolemaeus. Its diameter is 39 km. It was named after German-born British astronomer William Herschel. Just to the north is the flooded crater Spörer, and around 30 km due east lies the disintegrated crater Gyldén. About a crater diameter to the northwest (35 km) is the walled plain Flammarion, along the southern edge of the Sinus Medii. The rim of this crater is generally circular, although the western side is straight. It has a well-defined edge that is not significantly worn, and the inner walls are terraced. On the rough inner floor is a notable central rise. This peak is offset slightly to the west of the crater midpoint. The small crater Herschel G is attached to the south-southwest rim, and a tiny craterlet lies across the southern rim. Satellite craters By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Herschel (Martian Crater)
Herschel is a 304 kilometer impact crater in the Martian southern hemisphere, at 14.5°S, 130°E, located in the Mare Tyrrhenum region of Mars. The crater is jointly named after the seventeenth/eighteenth century father and son astronomers William Herschel and John Herschel. Moving Sand Dunes Mars Global Surveyor spacecraft originally photographed fields of dark sand dunes within Herschel. Images from the NASA Mars Reconnaissance Orbiter showed that sand dunes on the floor of the Herschel crater are not stationary (as previously believed), but moved over time. Images from photos taken by the Orbiter's High Resolution Imaging Science Experiment High Resolution Imaging Science Experiment is a camera on board the ''Mars Reconnaissance Orbiter'' which has been orbiting and studying Mars since 2006. The 65 kg (143 lb), US$40 million instrument was built under the direction o ... (HiRISE) on March 3, 2007 and December 1, 2010 show clear shifting of dunes and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Herschel (Mimantean Crater)
Herschel () is a large crater in the leading hemisphere of the Saturnian moon Mimas, centered on the equator at 112° longitude. It is named after the 18th-century astronomer William Herschel, who discovered Mimas in 1789. Size Herschel is the second-largest crater relative to its parent body of any equilibrium planetary moon in the Solar System after Tethys's crater Odysseus. It is so large that astronomers have expressed surprise that Mimas was not shattered by the impact that caused it. It measures across, almost one third the diameter of Mimas. Its walls are approximately high, parts of its floor are deep, and its central peak rises above the crater floor. If there were a crater of an equivalent scale on Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ... it would b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
