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List Of Near-Earth Asteroids By Distance From Sun
This list contains many notable near-Earth asteroids organised by their average distance from the Sun, and includes the planets A planet is a large, rounded astronomical body that is neither a star nor its remnant. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a young ... and distances for comparability. It does not pretend to completeness. References {{Portal bar, Astronomy, Stars, Spaceflight, Outer space, Solar System Near-Earth Asteroids, distance * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Near-Earth Asteroid
A near-Earth object (NEO) is any small Solar System body whose orbit brings it into proximity with Earth. By convention, a Solar System body is a NEO if its closest approach to the Sun (perihelion) is less than 1.3 astronomical units (AU). If a NEO's orbit crosses the Earth's orbit, and the object is larger than across, it is considered a potentially hazardous object (PHO). Most known PHOs and NEOs are asteroids, but a small fraction are comets. There are over 30,503 known near-Earth asteroids (NEAs) and over a hundred known short-period near-Earth comets (NECs). A number of solar-orbiting meteoroids were large enough to be tracked in space before striking the Earth. It is now widely accepted that collisions in the past have had a significant role in shaping the geological and biological history of the Earth. Asteroids as small as in diameter can cause significant damage to the local environment and human populations. Larger asteroids penetrate the atmosphere to the surf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3554 Amun
3554 Amun is an M-type Aten asteroid (meaning it crosses Earth's orbit) and a Venus-crosser. It was discovered on 4 March 1986 by Carolyn and Eugene Shoemaker at Mount Palomar Observatory. Its estimated diameter is 3.341 kilometers, making it one of the smallest known M-type asteroids. Amun was the fifth Aten asteroid to be numbered. Amun was once considered metallic, based on its M-type spectrum. In ''Mining the Sky ''Mining the Sky: Untold Riches from the Asteroids, Comets, and Planets'', is a 1997 book by University of Arizona Planetary Sciences professor emeritus John S. Lewis that describes possible routes for accessing extraterrestrial resources, either ...'', planetary scientist John S. Lewis calculated the value of 3554 Amun at $20 trillion. (6178) 1986 DA is another M-type near-Earth asteroid with lower inclination that is actually metallic. Amun passes closest to Venus, and in 1964, 2034, and 2103 comes within 10 Gm of it. References External link ... [...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 is 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 official ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
4769 Castalia
4769 Castalia (; '' prov. designation:'' ) is a near-Earth object and potentially hazardous asteroid of the Apollo group, approximately in diameter and was the first asteroid to be modeled by radar imaging. It was discovered on 9 August 1989, by American astronomer Eleanor Helin (Caltech) on photographic plates taken at Palomar Observatory in California. It is named after Castalia, a nymph in Greek mythology. It is also a Mars- and Venus-crosser asteroid. General information On 25 August 1989 Castalia passed (within eleven lunar distances) of Earth, allowing it to be observed with radar from the Arecibo Observatory by Scott Hudson (Washington State University) and Steven J. Ostro (JPL). The data allowed Hudson et al. to produce a three-dimensional model of the object. During the 1989 passage Castalia peaked at an apparent magnitude of 12. Castalia has a peanut shape, suggesting two approximately 800-meter-diameter pieces held together by their weak mutual gravity. Since the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1991 VG
1991 VG is a very small near-Earth object of the Apollo group, approximately in diameter. It was first observed by American astronomer James Scotti on 6 November 1991, using the Spacewatch telescope on Kitt Peak National Observatory near Tucson, Arizona, in the United States. On 6 December 1991 it passed about from the Moon. The asteroid then went unobserved from April 1992 until it was recovered by Paranal Observatory in May 2017. It was removed from the Sentry Risk Table on 1 June 2017. Earth-like orbit On 6 November 1991, Scotti discovered a faint object which was designated ''1991 VG'' soon after discovery. The object's heliocentric orbit was found to be very similar to Earth's orbit and it was calculated that it would make a close approach to Earth in the month after discovery at 1.2 lunar distances or on 5 December 1991. ''1991 VG'' also passed 0.0568 AU from Earth on 7 August 2017 and 0.0472 au on 11 February 2018. Given such an Earth-like orbit, the dyn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
4581 Asclepius
4581 Asclepius , provisional designation , is a sub-kilometer-sized asteroid, classified as near-Earth object and potentially hazardous asteroid of the Apollo group that makes close orbital passes with Earth. Discovered on 31 March 1989 by American astronomers Henry Holt and Norman Thomas at Palomar Observatory, Asclepius is named after the Greek demigod of medicine and healing. Asclepius passed by Earth on 22 March 1989 at a distance of . Although this exceeds the Moon's orbital radius, the close pass received attention at that time. "On the cosmic scale of things, that was a close call", said Dr. Henry Holt. Geophysicists estimate that collision with Asclepius would release energy comparable to the explosion of a 600 megaton Megaton may refer to: * A million tons * Megaton TNT equivalent, explosive energy equal to 4.184 petajoules * megatonne, a million tonnes, SI unit of mass Other uses * Olivier Megaton (born 1965), French film director, writer and editor * ''Me ... at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
10563 Izhdubar
1 (one, unit, unity) is a number representing a single or the only entity. 1 is also a numerical digit and represents a single unit (measurement), unit of counting or measurement. For example, a line segment of ''unit length'' is a line segment of length 1. In conventions of sign where zero is considered neither positive nor negative, 1 is the first and smallest Positive number, positive integer. It is also sometimes considered the first of the sequence (mathematics), infinite sequence of natural numbers, followed by 2, although by other definitions 1 is the second natural number, following 0. The fundamental mathematical property of 1 is to be a multiplicative identity, meaning that any number multiplied by 1 equals the same number. Most if not all properties of 1 can be deduced from this. In advanced mathematics, a multiplicative identity is often denoted 1, even if it is not a number. 1 is by convention not considered a prime number; this was not universally ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
54509 YORP
54509 YORP, provisional designation , is an Earth co-orbital asteroid discovered on 3 August 2000 by the Lincoln Laboratory Near-Earth Asteroid Research (LINEAR) Team at Lincoln Laboratory Experimental Test Site in Socorro, New Mexico. Measurements of the rotation rate of this object provided the first observational evidence of the YORP effect, hence the name of the asteroid. The asteroid's rate of rotation is increasing at the rate of (2.0 ± 0.2) × 10−4 deg/day2 which between 2001 and 2005 caused the asteroid to rotate about 250° further than its spin rate in 2001 would have predicted. Simulations of the asteroid suggest that it may reach a rotation period of ~20 seconds near the end of its expected lifetime. The simulations also ruled out the possibility that close encounters with the Earth have been the cause of the increased spin rate. On 2 January 2104, asteroid YORP will pass from Earth. Gallery See also * 1620 Geographos * 1862 Apollo * 25143 Itokawa 2 ... [...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 10,485, making the class the largest group of s (''cf''. the , Amor and Atira asteroids), [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth (planet)
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 surface is made up of the ocean, dwarfing Earth's polar ice, lakes, and rivers. The remaining 29% of Earth's surface is land, consisting of continents and islands. Earth's surface layer is formed of several slowly moving tectonic plates, which interact to produce mountain ranges, volcanoes, and earthquakes. Earth's liquid outer core generates the magnetic field that shapes the magnetosphere of the Earth, deflecting destructive solar winds. The atmosphere of the Earth consists mostly of nitrogen and oxygen. Greenhouse gases in the atmosphere like carbon dioxide (CO2) trap a part of the energy from the Sun close to the surface. Water vapor is widely present in the atmosphere and forms clouds that cover most of the planet. More solar energy is rec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
3753 Cruithne
3753 Cruithne is a Q-type, Aten asteroid in orbit around the Sun in 1:1 orbital resonance with Earth, making it a co-orbital object. It is an asteroid that, relative to Earth, orbits the Sun in a bean-shaped orbit that effectively describes a horseshoe, and that can change into a quasi-satellite orbit. Cruithne does not orbit Earth and at times it is on the other side of the Sun, placing Cruithne well outside of Earth's Hill sphere. Its orbit takes it near the orbit of Mercury and outside the orbit of Mars. Cruithne orbits the Sun in about one Earth year, but it takes 770 years for the series to complete a horseshoe-shaped movement around Earth. The name ''Cruithne'' is from Irish and refers to the early Picts (Old Irish: ''Cruthin'') in the ''Annals of Ulster''Cruithne: Asteroid 3753 . Western Washington University Planetarium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth Co-orbital Asteroid
In astronomy, a co-orbital configuration is a configuration of two or more astronomical objects (such as asteroids, moons, or planets) orbiting at the same, or very similar, distance from their primary, i.e. they are in a 1:1 mean-motion resonance. (or 1:−1 if orbiting in opposite directions). There are several classes of co-orbital objects, depending on their point of libration. The most common and best-known class is the trojan, which librates around one of the two stable Lagrangian points (Trojan points), and , 60° ahead of and behind the larger body respectively. Another class is the horseshoe orbit, in which objects librate around 180° from the larger body. Objects librating around 0° are called quasi-satellites. An exchange orbit occurs when two co-orbital objects are of similar masses and thus exert a non-negligible influence on each other. The objects can exchange semi-major axes or eccentricities when they approach each other. Parameters Orbital parameters that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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