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R-type Asteroid
R-type asteroids are moderately bright, relatively uncommon inner-belt asteroids that are spectrally intermediate between the V and A-type asteroids. The spectrum shows distinct olivine and pyroxene features at 1 and 2 micrometres, with a possibility of plagioclase. Shortwards of 0.7 μm the spectrum is very reddish. The IRAS mission has classified 4 Vesta, 246 Asporina, 349 Dembowska, 571 Dulcinea and 937 Bethgea as type R; however, the re-classification of Vesta, the V archetype, is debatable. Of these bodies, only 349 Dembowska is recognized as being type R when all wavelengths are taken into account. List As of February 2019, at least 5 asteroids have been classified as R-type: References 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 differentia ... [...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 co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
571 Dulcinea
Dulcinea (minor planet designation: 571 Dulcinea) is an asteroid orbiting in the inner main belt. It was named after Dulcinea, a character from Miguel de Cervantes' novel ''Don Quixote''. This is classified as a stony S-type asteroid and it is the second largest member of the Erigone family, Erigone collisional family. References External links * * Erigone asteroids Background asteroids, 000571 Discoveries by Paul Götz Named minor planets Don Quixote, 571 Dulcinea Slow rotating minor planets, 000571 S-type asteroids (Tholen), 000571 S-type asteroids (SMASS), 000571 Astronomical objects discovered in 1905, 19050904 {{beltasteroid-stub ... [...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.Thoma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2371 Dimitrov
__NOTOC__ Year 371 (CCCLXXI) was a common year starting on Saturday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Augustus and Petronius (or, less frequently, year 1124 '' Ab urbe condita''). The denomination 371 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 * The fortified cities of the Danube, with Sirmium ( Pannonia) at the forefront, contribute to stop an invasion of the Quadi. Persia * The neo- Persian Empire attains the zenith of its power under King Shapur II, as the Romans renew their war against Persia. Hostilities will continue for the next 5 years. Asia * Baekje forces storm the Goguryeo capital in P'yongyang (Korea). * Sosurim becomes king of Goguryeo. By topic Art and Science * Roman poet Ausonius writes of a voyage on the Rhine and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1904 Massevitch
1904 Massevitch ( ''prov. designation'': ) is a background asteroid from the central region of the asteroid belt. It was discovered on 9 May 1972, by the Russian astronomer Tamara Smirnova at the Crimean Astrophysical Observatory in Nauchnyj, on the Crimean peninsula. The uncommon R-type asteroid has a rotation period of 5.3 hours and measures approximately in diameter. It was later named after Russian astrophysicist Alla Masevich. Orbit ''Massevitch'' orbits the Sun in the central main-belt at a distance of 2.5–2.9 AU once every 4 years and 7 months (1,662 days). Its orbit has an eccentricity of 0.07 and an inclination of 13 ° with respect to the ecliptic. It was first identified as at Goethe Link Observatory in 1949, extending the body's observation arc by 23 years prior to its discovery observation. Naming This minor planet was named after Russian astrophysicist and astronomer Alla Genrichovna Massevitch (born 1918), vice-president of the Astronomical Council ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minor Planet Designation
A formal minor-planet designation is, in its final form, a number–name combination given to a minor planet (asteroid, centaur, trans-Neptunian object and dwarf planet but not comet). Such designation always features a leading number (catalog or IAU number) assigned to a body once its orbital path is sufficiently secured (so-called "numbering"). The formal designation is based on the minor planet's provisional designation, which was previously assigned automatically when it had been observed for the first time. Later on, the provisional part of the formal designation may be replaced with a name (so-called "naming"). Both formal and provisional designations are overseen by the Minor Planet Center (MPC), a branch of the International Astronomical Union. Currently, a number is assigned only after the orbit has been secured by four well-observed oppositions. For unusual objects, such as near-Earth asteroids, numbering might already occur after three, maybe even only two, oppositio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
937 Bethgea
937 Bethgea is a background asteroid from the inner region of the asteroid belt. It was discovered on 12 September 1920 by German astronomer Karl Wilhelm Reinmuth, from Heidelberg Heidelberg (; Palatine German language, Palatine German: ''Heidlberg'') is a city in the States of Germany, German state of Baden-Württemberg, situated on the river Neckar in south-west Germany. As of the 2016 census, its population was 159,914 .... Photometric observations of this asteroid made at the Torino Observatory in Italy during 1990–1991 were used to determine a synodic rotation period of 8.356 ± 0.006 hours. References External links * * 000937 Discoveries by Karl Wilhelm Reinmuth Named minor planets 000937 19200912 {{S-beltasteroid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
349 Dembowska
Dembowska ( minor planet designation: 349 Dembowska) is a large asteroid of the main belt, discovered on 9 December 1892, by the French astronomer Auguste Charlois while working at the observatory in Nice, France. It is named in honor of the Baron Hercules Dembowski, an Italian astronomer who made significant contributions to research on double and multiple stars. Orbiting just inside the prominent 7:3 resonance with Jupiter, 349 Dembowska is among the largest asteroids in the main belt with an estimated diameter of ~140 km. It has a rotational period of 4.7012 hours, and is classified as an R-type asteroid for the presence of strong absorption lines in olivine and pyroxene with little or no metals. It may have undergone partial melting/ differentiation. 349 Dembowska has an unusually high albedo of 0.384. Of the asteroids with a diameter greater than 75 km, only 4 Vesta has a higher known albedo. Dembowska and 16 Psyche have orbits that repeat themselves almost exac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
V-type Asteroid
A V-type asteroid or Vestoid is an asteroid whose spectral type is that of 4 Vesta. Approximately 6% of main-belt asteroids are vestoids, with Vesta being by far the largest of them. They are relatively bright, and rather similar to the more common S-type asteroid, which are also made up of stony irons and ordinary chondrites, with V-types containing more pyroxene than S-types. A large proportion of vestoids have orbital elements similar to those of Vesta, either close enough to be part of the Vesta family, or having similar eccentricities and inclinations but with a semi-major axis lying between about 2.18 AU and the 3:1 Kirkwood gap at 2.50 AU. This suggests that they originated as fragments of Vesta's crust. There seem to be two populations of Vestoids, one created 2 billion years ago and the other 1 billion years ago, coming respectively from the enormous southern-hemisphere craters Veneneia and Rheasilvia. Fragments that ended up in the 3:1 Jupiter resonance were perturbed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
246 Asporina
Asporina ( minor planet designation: 246 Asporina) is a sizeable main-belt asteroid. It is classified as one of the few A-type asteroids. It was discovered by A. Borrelly on 6 March 1885 in Marseilles and was named after Asporina, a goddess worshipped on Mount Asporenus, Asia Minor. The spectrum of 246 Asporina reveals the strong presence of the mineral olivine The mineral olivine () is a magnesium iron silicate with the chemical formula . It is a type of nesosilicate or orthosilicate. The primary component of the Earth's upper mantle, it is a common mineral in Earth's subsurface, but weathers quickl ..., a relative rarity in the asteroid belt. References External links The Asteroid Orbital Elements DatabaseAsteroid Lightcurve Data File* * Background asteroids Asporina Asporina A-type asteroids (Tholen) A-type asteroids (SMASS) 18850306 {{Beltasteroid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
