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Q-type Asteroid
Q-type asteroids are relatively uncommon inner-belt asteroids with a strong, broad 1 micrometre olivine and pyroxene feature, and a spectral slope that indicates the presence of metal. There are absorption features shortwards and longwards of 0.7 μm, and the spectrum is generally intermediate between the V and S-type. Q-type asteroids are spectrally more similar to ordinary chondrite meteorites (types H, L, LL) than any other asteroid type. This has led scientists to speculate that they are abundant, but only about 20 of this type has been characterized. Examples of Q-type asteroids are: 1862 Apollo, 2102 Tantalus, 3753 Cruithne, 6489 Golevka, and 9969 Braille. See also *Asteroid spectral types An asteroid spectral type is assigned to asteroids based on their emission 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 ... References A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asteroid Belt
The asteroid belt is a torus-shaped region in the Solar System, located roughly between the orbits of the planets Jupiter and Mars. It contains a great many solid, irregularly shaped bodies, of many sizes, but much smaller than planets, called asteroids or minor planets. This asteroid belt is also called the main asteroid belt or main belt to distinguish it from other asteroid populations in the Solar System such as near-Earth asteroids and trojan asteroids. The asteroid belt is the smallest and innermost known circumstellar disc in the Solar System. About 60% of its mass is contained in the four largest asteroids: Ceres, Vesta, Pallas, and Hygiea. The total mass of the asteroid belt is calculated to be 3% that of the Moon. Ceres, the only object in the asteroid belt large enough to be a dwarf planet, is about 950 km in diameter, whereas Vesta, Pallas, and Hygiea have mean diameters less than 600 km. The remaining bodies range down to the size of a dust particle. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LL Chondrite
The LL chondrites are a group of stony meteorites, the least abundant group of the ordinary chondrites, accounting for about 10–11% of observed ordinary-chondrite falls and 8–9% of all meteorite falls (see meteorite fall statistics). The ordinary chondrites are thought to have originated from three parent asteroids, with the fragments making up the H chondrite, L chondrite and LL chondrite groups respectively. The composition of the Chelyabinsk meteorite is that of a LL chondrite meteorite. The material makeup of Itokawa, the asteroid visited by the Hayabusa spacecraft which landed on it and brought particles back to Earth also proved to be type LL chondrite. Name LL stands for Low (total) iron, Low metal. Chemical composition They contain 19–22% total iron and only 0.3–3% metallic iron. That means that most of the iron is present as iron oxide (FeO) in the silicates; olivine contains 26 to 32 mol% fayalite (Fa). The most abundant minerals are hypersthene (a pyroxen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asteroid Spectral Classes
An asteroid is a minor planet of the inner Solar System. Sizes and shapes of asteroids vary significantly, ranging from 1-meter rocks to a dwarf planet almost 1000 km in diameter; they are rocky, metallic or icy bodies with no atmosphere. Of the roughly one million known asteroids the greatest number are located between the orbits of Mars and Jupiter, approximately 2 to 4 AU from the Sun, in the main asteroid belt. Asteroids are generally classified to be of three types: C-type, M-type, and S-type. These were named after and are generally identified with carbonaceous, metallic, and silicaceous compositions, respectively. The size of asteroids varies greatly; the largest, Ceres, is almost across and qualifies as a dwarf planet. The total mass of all the asteroids combined is only 3% that of Earth's Moon. The majority of main belt asteroids follow slightly elliptical, stable orbits, revolving in the same direction as the Earth and taking from three to six years to comple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asteroid Spectral Types
An asteroid spectral type is assigned to asteroids based on their emission 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 (silicaceous) 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.Thomas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
9969 Braille
9969 Braille, provisional designation , is an eccentric, rare-type and elongated asteroid from the innermost regions of the asteroid belt, classified as Mars-crosser and slow rotator, approximately 1–2 kilometers in diameter. It was discovered in 1992, by astronomers at Palomar Observatory and later named after Louis Braille, the inventor of the writing system for the blind. It was photographed in closeup by the spacecraft Deep Space 1 in 1999, but a malfunction resulted in indistinct images. Discovery and naming Discovered on May 27, 1992, by E. F. Helin and K. J. Lawrence working at the Palomar observatory as part of NASA's Planet-Crossing Asteroid Survey, it was given the provisional designation . Later, it was named Braille in honour of Louis Braille as suggested by Kennedy Space Center software engineer Kerry Babcock in The Planetary Society's contest titled "Name That Asteroid". The official naming citation was published by the Minor Planet Center on 28 July 199 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
6489 Golevka
6489 Golevka is an Apollo, Mars-crosser, and Alinda asteroid discovered in 1991 by Eleanor F. Helin. Its name has a complicated origin. In 1995, Golevka was studied simultaneously by three radar observatories across the world: Goldstone in California, Yevpatoria RT-70 radio telescope in Ukraine (Yevpatoria is sometimes romanized as Evpatoria) and Kashima in Japan. 'Golevka' comes from the first few letters of each observatory's name; it was proposed by the discoverer following a suggestion by Alexander L. Zaitsev. Golevka is a small object, measuring 0.6 × 1.4 km. The radar observations revealed that it has a very strange, angular shape that looks different depending on the direction. In 2003 the Yarkovsky effect was first observed at work by high-precision radar observations of Golevka. Between 1991 and 2003, the small force of the Yarkovsky effect caused a shift of from what would be expected based on only gravitational interactions. This helped evaluate th ... [...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] |
2102 Tantalus
2102 Tantalus (1975 YA) is an Apollo asteroid discovered on December 27, 1975, by C. Kowal at Palomar Observatory. It is a Q-type asteroid. 2102 Tantalus is a potentially hazardous asteroid (PHA) because its minimum orbit intersection distance (MOID) is less than 0.05 AU and its diameter is greater than 150 meters. The Earth-MOID is . Its orbit is well-determined for the next several hundred years. It will pass from Earth on 2038-Dec-27, which is just slightly closer than the 1975-Dec-26 approach of 0.046 AU. The asteroid is about 2–4 km in diameter. The shape of 2102 Tantalus is estimated to be roughly spherical in outline and fairly symmetrical; the surface is thought to be covered in a fine-grained regolith Regolith () is a blanket of unconsolidated, loose, heterogeneous superficial deposits covering solid rock. It includes dust, broken rocks, and other related materials and is present on Earth, the Moon, Mars, some asteroids, and other terrestr .... Referen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 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-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 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, due to the fact that it was a lost asteroid for more than 40 years and other bodies were numbered in the meantime. The anal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
L Chondrite
The L type ordinary chondrites are the second most common group of meteorites, accounting for approximately 35% of all those catalogued, and 40% of the ordinary chondrites. The ordinary chondrites are thought to have originated from three parent asteroids, with the fragments making up the H chondrite, L chondrite and LL chondrite groups respectively. Name Their name comes from their relatively low iron abundance, with respect to the H chondrites, which are about 20–25% iron by weight. Historically, the L chondrites have been named ''hypersthene chondrites'' or ''olivine hypersthene chondrites'' for the dominant minerals, but these terms are now obsolete. Chemical composition Characteristic is the fayalite content (Fa) in olivine of 21 to 25 mol%. About 4–10% iron–nickel is found as a free metal, making these meteorites magnetic, but not as strongly as the H chondrites. Mineralogy The most abundant minerals are olivine and hypersthene (an orthopyroxene), as well as ir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asteroid
An asteroid is a minor planet of the inner Solar System. Sizes and shapes of asteroids vary significantly, ranging from 1-meter rocks to a dwarf planet almost 1000 km in diameter; they are rocky, metallic or icy bodies with no atmosphere. Of the roughly one million known asteroids the greatest number are located between the orbits of Mars and Jupiter, approximately 2 to 4 AU from the Sun, in the main asteroid belt. Asteroids are generally classified to be of three types: C-type, M-type, and S-type. These were named after and are generally identified with carbonaceous, metallic, and silicaceous compositions, respectively. The size of asteroids varies greatly; the largest, Ceres, is almost across and qualifies as a dwarf planet. The total mass of all the asteroids combined is only 3% that of Earth's Moon. The majority of main belt asteroids follow slightly elliptical, stable orbits, revolving in the same direction as the Earth and taking from three to six years to comple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
H Chondrite
The H type ordinary chondrites are the most common type of meteorite, accounting for approximately 40% of all those catalogued, 46% of the ordinary chondrites, and 44% of all chondrites. The ordinary chondrites are thought to have originated from three parent asteroids, whose fragments make up the H chondrite, L chondrite and LL chondrite groups respectively. Name The name comes from their High iron abundance, with respect to other ordinary chondrites. Historically, the H chondrites have been named ''bronzite chondrites'' or ''olivine bronzite chondrites'' for the dominant minerals, but these terms are now obsolete. Parent body A probable parent body for this group is the S-type asteroid 6 Hebe, with less likely candidates being 3 Juno and 7 Iris. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
