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1862 Apollo
1862 Apollo is a stony asteroid, approximately 1.5 kilometers in diameter, classified as a near-Earth object (NEO). It was discovered by German astronomer Karl Reinmuth at Landessternwarte Heidelberg-Königstuhl, Heidelberg Observatory on 24 April 1932, but lost and not recovered until 1973. It is the namesake and the first recognized member of the Apollo asteroids, a subgroup of NEOs which are Earth-crosser asteroid, Earth-crossers, that is, they cross the orbit of the Earth when viewed perpendicularly to the ecliptic plane (crossing an orbit is a more general term than actually intersecting it). In addition, since Apollo's orbit is highly orbital eccentricity, eccentric, it crosses the orbits of Venus and Mars and is therefore called a Venus-crosser and Mars-crosser as well. Although Apollo was the first Apollo asteroid to be discovered, its official IAU-number (1862) is higher than that of some other Apollo asteroids such as 1566 Icarus, because it was a Lost minor planet, l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1862 Apollo Symbol (bold)
Year 186 (Roman numerals, CLXXXVI) was a common year starting on Saturday of the Julian calendar. At the time, it was known as the Year of the Consulship of Aurelius and Glabrio (or, less frequently, year 939 ''Ab urbe condita''). The denomination 186 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years. Events By place Roman Empire * Peasants in Gaul stage an anti-tax uprising under Maternus (rebel), Maternus. * Roman governor Pertinax escapes an assassination attempt, by British usurpers. New Zealand * The Hatepe eruption, Hatepe volcanic eruption extends Lake Taupō and makes skies red across the world. However, recent radiocarbon dating by R. Sparks has put the date at 233 AD ± 13 (95% confidence). Births * Ma Liang (Three Kingdoms), Ma Liang, Chinese official of the Shu Han state (d. 222) Deaths * April 21 – Apollonius the Apologist, Christian martyr * Bi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asteroid Color Indices
An asteroid spectral type is assigned to asteroids based on their reflectance spectrum, color, and sometimes albedo. These types are thought to correspond to an asteroid's surface composition. For small bodies that are not internally differentiated, the surface and internal compositions are presumably similar, while large bodies such as Ceres and Vesta are known to have internal structure. Over the years, there has been a number of surveys that resulted in a set of different taxonomic systems such as the Tholen, SMASS and Bus–DeMeo classifications. Taxonomic systems In 1975, astronomers Clark R. Chapman, David Morrison, and Ben Zellner developed a simple taxonomic system for asteroids based on color, albedo, and spectral shape. The three categories were labelled " C" for dark carbonaceous objects, " S" for stony (siliceous) objects, and "U" for those that did not fit into either C or S. This basic division of asteroid spectra has since been expanded and clarified.T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asteroid Moon
A minor-planet moon is an astronomical object that orbits a minor planet as its natural satellite. , there are 457 minor planets known or suspected to have moons. Discoveries of minor-planet moons (and binary objects, in general) are important because the determination of their orbits provides estimates on the mass and density of the primary, allowing insights into their physical properties that are generally not otherwise accessible. Several of the moons are quite large compared to their primaries: 90 Antiope, Mors–Somnus and Sila–Nunam (95%), Patroclus–Menoetius, Altjira and Lempo–Hiisi (90%, with Lempo–Paha at 50%). The largest known minor-planet moon in ''absolute'' size is Pluto's largest moon Charon, which itself has about half the diameter of Pluto. There are also several known ring systems around distant objects (see: '' Rings of Chariklo'' and ''Chiron''). Terminology In addition to the terms ''satellite'' and ''moon'', the term "binary" (binary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
68 Leto
68 Leto is a large main belt asteroid that is orbiting the Sun. The asteroid was discovered by German astronomer Robert Luther on April 29, 1861, and is named after Leto, the mother of Apollo and Artemis in Greek mythology. It orbits at a distance of 2.78112 AU over 4.64 years and has an orbital eccentricity of 0.187. The orbital plane is inclined at an angle of 7.97° to the ecliptic. Photometric observations of 68 Leto during 1997 provided a rotation period of . It has an estimated cross-sectional size of 123 km. The spectral type is S, suggesting a stony, silicate composition. References External links * * Background asteroids Leto Leto Leto In ancient Greek mythology and Ancient Greek religion, religion, Leto (; ) is a childhood goddess, the daughter of the Titans Coeus and Phoebe (Titaness), Phoebe, the sister of Asteria, and the mother of Apollo and Artemis.Hesiod, ''Theogony' ... S-type asteroids (Tholen) 18610429 {{S-beltasteroid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
5731 Zeus
5731 Zeus is an Apollo asteroid and near-Earth object discovered on 4 November 1988, by Carolyn Shoemaker at Palomar Observatory. Based on its observed brightness and assumed albedo Albedo ( ; ) is the fraction of sunlight that is Diffuse reflection, diffusely reflected by a body. It is measured on a scale from 0 (corresponding to a black body that absorbs all incident radiation) to 1 (corresponding to a body that reflects ... it is estimated to have a diameter between 2.1 and 4.7 km. References External links * * * 005731 Discoveries by Carolyn S. Shoemaker Discoveries by Eugene Merle Shoemaker Named minor planets 19881104 {{NE-asteroid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
YORP Effect
The Yarkovsky–O'Keefe–Radzievskii–Paddack effect, or YORP effect for short, changes the rotation state of a small astronomical body – that is, the body's spin rate and the obliquity of its pole(s) – due to the scattering of solar radiation off its surface and the emission of its own thermal radiation. The YORP effect is typically considered for asteroids with their heliocentric orbit in the Solar System. The effect is responsible for the creation of binary and tumbling asteroids as well as for changing an asteroid's pole towards 0 °, 90°, or 180° relative to the ecliptic plane and so modifying its heliocentric radial drift rate due to the Yarkovsky effect. Term The term was coined by David P. Rubincam in 2000 to honor four important contributors to the concepts behind the so-named YORP effect. In the 19th century, Ivan Yarkovsky realized that the thermal radiation escaping from a body warmed by the Sun carries off momentum as well as heat. Translated into m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lost Minor Planet
Lost or LOST may refer to getting lost, or to: Arts, entertainment, and media Television * ''Lost'' (TV series), a 2004 American drama series about people who become stranded on a mysterious island * ''Lost'' (2001 TV series), a short-lived American and UK reality series * ''Lost'' (South Korean TV series), a 2021 South Korean series * "Lost" (''The Bill''), a 1985 episode * "Lost" (''Stargate Universe''), an episode of science fiction series ''Stargate Universe'' *"Lost", an episode of ''Unleashed!'' *"Lost", an episode of the Canadian documentary TV series ''Mayday'' *"Lost", an episode of Disney's ''So Weird'' * "The Lost" (''Class''), an episode of the first series of the ''Doctor Who'' spin-off series ''Class'' Films * ''Lost'' (1950 film), a Mexican film directed by Fernando A. Rivero * ''Lost'' (1956 film), a British thriller starring David Farrar * ''Lost'' (1983 film), an American film directed by Al Adamson * ''Lost!'' (film), a 1986 Canadian film directed by Peter R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1566 Icarus
1566 Icarus ( ; '' provisional designation'': ) is a large near-Earth object of the Apollo group and the lowest numbered potentially hazardous asteroid. It has an extremely eccentric orbit (0.83) and measures approximately in diameter. In 1968, it became the first asteroid ever observed by radar. Its orbit brings it closer to the Sun than Mercury and further out than the orbit of Mars, which also makes it a Mercury-, Venus-, and Mars-crossing asteroid. This stony asteroid and relatively fast rotator with a period of 2.27 hours was discovered on 27 June 1949, by German astronomer Walter Baade at the Palomar Observatory in California. It was named after the mythological Icarus. Orbit and classification Icarus orbits the Sun at a distance of 0.19–1.97 AU once every 13 months (409 days; semi-major axis of 1.08 AU). Its orbit has an eccentricity of 0.83 and an inclination of 23 ° with respect to the ecliptic. The body's observation arc begins with its offic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbital Eccentricity
In astrodynamics, the orbital eccentricity of an astronomical object is a dimensionless parameter that determines the amount by which its orbit around another body deviates from a perfect circle. A value of 0 is a circular orbit, values between 0 and 1 form an elliptic orbit, 1 is a parabolic escape orbit (or capture orbit), and greater than 1 is a hyperbola. The term derives its name from the parameters of conic sections, as every Kepler orbit is a conic section. It is normally used for the isolated two-body problem, but extensions exist for objects following a rosette orbit through the Galaxy. Definition In a two-body problem with inverse-square-law force, every orbit is a Kepler orbit. The eccentricity of this Kepler orbit is a non-negative number that defines its shape. The eccentricity may take the following values: * Circular orbit: * Elliptic orbit: * Parabolic trajectory: * Hyperbolic trajectory: The eccentricity is given by e = \sqrt where ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth-crosser Asteroid
An Earth-crosser is a near-Earth asteroid whose orbit crosses that of Earth as observed from the ecliptic pole of Earth's orbit. The known numbered Earth-crossers are listed here. Those Earth-crossers whose semi-major axes are smaller than Earth's are Aten asteroids; the remaining ones are Apollo asteroids. ''(See also the Amor asteroids.)'' An asteroid with an Earth-crossing orbit is not necessarily in danger of colliding with Earth. The orbit of an Earth-crossing asteroid may not even intersect with that of Earth. This apparent contradiction arises because many asteroids have highly inclined orbits, so although they may have a perihelion less than that of Earth, their paths can never cross. An asteroid for which there is some possibility of a collision with Earth at a future date and which is above a certain size is classified as a potentially hazardous asteroid (PHA). Specifically, an asteroid is a PHA if its Earth minimum orbital intersection distance (MOID) is <0.05 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apollo Asteroid
The Apollo asteroids are a group of near-Earth asteroids named after 1862 Apollo, discovered by German astronomer Karl Reinmuth in the 1930s. They are Earth-crossing asteroids that have an orbital semi-major axis greater than that of the Earth (a > 1 AU) but perihelion distances less than the Earth's aphelion distance (q < 1.017 AU). , the number of known Apollo asteroids is 21,083, making the class the largest group of near-Earth objects (''cf''. the Aten, Amor and Atira asteroids), of which 1,742 are [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karl Reinmuth
Karl Wilhelm Reinmuth (4 April 1892 in Heidelberg – 6 May 1979 in Heidelberg) was a German astronomer and a prolific discoverer of 395 minor planets. Scientific career From 1912 to 1957, Reinmuth was working as an astronomer at the Heidelberg Observatory () an astronomical observatory on the Königstuhl hill above Heidelberg in southern Germany. He was a member at the minor planet studies group at Astronomisches Rechen-Institut between 1947 and 1950, and later became "Oberobservator" or chief-observer at Heidelberg Observatory until his retirement in 1957. Reinmuth obtained more than 12,500 precise astrometric measurements of minor planets' positions on photographic plates, an enormous accomplishment before computer-based assistance existed. Honours The outer main-belt asteroid 1111 Reinmuthia, discovered by himself at Heidelberg in 1912, was named in his honour (). Discoveries Among his most notable discoveries are the two near-Earth objects (NEOs) 1862 Apol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
