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3352 McAuliffe
3352 McAuliffe (), provisional designation , is a rare-type asteroid and suspected binary system, classified as near-Earth object of the Amor group, approximately 2 kilometers in diameter. It was discovered on 6 February 1981, by American astronomer Norman Thomas at Lowell's Anderson Mesa Station near Flagstaff, Arizona, United States. Originally, this asteroid was the target of the 1998 Deep Space 1 mission, but that mission was eventually rerouted to 9969 Braille. It was named in memory of Challenger crew member Christa McAuliffe. Orbit ''McAuliffe'' orbits the Sun at a distance of 1.2–2.6 AU once every 2 years and 7 months (941 days). Its orbit has an eccentricity of 0.37 and an inclination of 5 ° with respect to the ecliptic. It has an ''Earth minimum orbital intersection distance'' of , which translates into 79.5 lunar distances. Due to its eccentric orbit, ''McAuliffe'' is also a Mars-crosser. As no precoveries were taken, and no prior identifications were m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Norman G
Norman or Normans may refer to: Ethnic and cultural identity * The Normans, a people partly descended from Norse Vikings who settled in the territory of Normandy in France in the 10th and 11th centuries ** People or things connected with the Norman conquest of southern Italy in the 11th and 12th centuries ** Norman dynasty, a series of monarchs in England and Normandy ** Norman architecture, romanesque architecture in England and elsewhere ** Norman language, spoken in Normandy ** People or things connected with the French region of Normandy Arts and entertainment * ''Norman'' (film), a 2010 drama film * '' Norman: The Moderate Rise and Tragic Fall of a New York Fixer'', a 2016 film * ''Norman'' (TV series), a 1970 British sitcom starring Norman Wisdom * ''The Normans'' (TV series), a documentary * "Norman" (song), a 1962 song written by John D. Loudermilk and recorded by Sue Thompson * "Norman (He's a Rebel)", a song by Mo-dettes from ''The Story So Far'', 1980 Businesses * ... [...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] |
Absolute Magnitude
Absolute magnitude () is a measure of the luminosity of a celestial object on an inverse Logarithmic scale, logarithmic Magnitude (astronomy), astronomical magnitude scale. An object's absolute magnitude is defined to be equal to the apparent magnitude that the object would have if it were viewed from a distance of exactly , without Extinction (astronomy), extinction (or dimming) of its light due to absorption by Interstellar medium, interstellar matter and cosmic dust. By hypothetically placing all objects at a standard reference distance from the observer, their luminosities can be directly compared among each other on a magnitude scale. As with all astronomical magnitude (astronomy), magnitudes, the absolute magnitude can be specified for different wavelength ranges corresponding to specified Filter (optics), filter bands or passbands; for stars a commonly quoted absolute magnitude is the absolute visual magnitude, which uses the visual (V) band of the spectrum (in the UBV phot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomical Albedo
Albedo (; ) is the measure of the diffuse reflection of solar radiation out of the total solar radiation and measured on a scale from 0, corresponding to a black body that absorbs all incident radiation, to 1, corresponding to a body that reflects all incident radiation. Surface albedo is defined as the ratio of radiosity ''J''e to the irradiance ''E''e (flux per unit area) received by a surface. The proportion reflected is not only determined by properties of the surface itself, but also by the spectral and angular distribution of solar radiation reaching the Earth's surface. These factors vary with atmospheric composition, geographic location, and time (see position of the Sun). While bi-hemispherical reflectance is calculated for a single angle of incidence (i.e., for a given position of the Sun), albedo is the directional integration of reflectance over all solar angles in a given period. The temporal resolution may range from seconds (as obtained from flux measurements) to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyroxene
The pyroxenes (commonly abbreviated to ''Px'') are a group of important rock-forming inosilicate minerals found in many igneous and metamorphic rocks. Pyroxenes have the general formula , where X represents calcium (Ca), sodium (Na), iron (Fe II) or magnesium (Mg) and more rarely zinc, manganese or lithium, and Y represents ions of smaller size, such as chromium (Cr), aluminium (Al), magnesium (Mg), cobalt (Co), manganese (Mn), scandium (Sc), titanium Titanium is a chemical element with the symbol Ti and atomic number 22. Found in nature only as an oxide, it can be reduced to produce a lustrous transition metal with a silver color, low density, and high strength, resistant to corrosion in ... (Ti), vanadium (V) or even iron (Fe II) or (Fe III). Although aluminium substitutes extensively for silicon in silicates such as feldspars and amphiboles, the substitution occurs only to a limited extent in most pyroxenes. They share a common structure consisting of single chains of si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
PanSTARRS
The Panoramic Survey Telescope and Rapid Response System (Pan-STARRS1; obs. code: F51 and Pan-STARRS2 obs. code: F52) located at Haleakala Observatory, Hawaii, US, consists of astronomical cameras, telescopes and a computing facility that is surveying the sky for moving or variable objects on a continual basis, and also producing accurate astrometry and photometry of already-detected objects. In January 2019 the second Pan-STARRS data release was announced. At 1.6 petabytes, it is the largest volume of astronomical data ever released. Description The Pan-STARRS Project is a collaboration between the University of Hawaii Institute for Astronomy, MIT Lincoln Laboratory, Maui High Performance Computing Center and Science Applications International Corporation. Telescope construction was funded by the U.S. Air Force. By detecting differences from previous observations of the same areas of the sky, Pan-STARRS is discovering many new asteroids, comets, variable stars, supern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 quickly on the surface. For this reason, olivine has been proposed as a good candidate for accelerated weathering to sequester carbon dioxide from the Earth's oceans and atmosphere, as part of climate change mitigation. Olivine also has many other historical uses, such as the gemstone peridot (or chrysolite), as well as industrial applications like metalworking processes. The ratio of magnesium to iron varies between the two endmembers of the solid solution series: forsterite (Mg-endmember: ) and fayalite (Fe-endmember: ). Compositions of olivine are commonly expressed as molar percentages of forsterite (Fo) and fayalite (Fa) (''e.g.'', Fo70Fa30). Forsterite's melting temperature is unusually high at atmospheric pressure, almost , while ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Observation Arc
In observational astronomy, the observation arc (or arc length) of a Solar System body is the time period between its earliest and latest observations, used for tracing the body's path. It is usually given in days or years. The term is mostly used in the discovery and tracking of asteroids and comets. Arc length has the greatest influence on the accuracy of an orbit. The number and spacing of intermediate observations has a lesser effect. Short arcs A very short arc leaves a high uncertainty parameter. The object might be in one of many different orbits, at many distances from Earth. In some cases, the initial arc was too short to determine if the object was in orbit around the Earth, or orbiting out in the asteroid belt. With a 1-day observation arc, was thought to be a trans-Neptunian dwarf planet, but is now known to be a 1 km main-belt asteroid. With an observation arc of 3 days, was thought to be a Mars-crossing asteroid that could be a threat to Earth, but was later ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Precoveries
In astronomy, precovery (short for pre-discovery recovery) is the process of finding the image of an object in images or photographic plates predating its discovery, typically for the purpose of calculating a more accurate orbit. This happens most often with minor planets, but sometimes a comet, a dwarf planet, a natural satellite, or a star is found in old archived images; even exoplanet precovery observations have been obtained. "Precovery" refers to a pre-discovery image; "recovery" refers to imaging of a body which was lost to our view (as behind the Sun), but is now visible again ''(also see lost minor planet and lost comet)''. Orbit determination requires measuring an object's position on multiple occasions. The longer the interval between observations, the more accurately the orbit can be calculated; however, for a newly discovered object, only a few days' or weeks' worth of measured positions may be available, sufficient only for a preliminary (imprecise) orbit calculatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mars-crosser
A Mars-crossing asteroid (MCA, also Mars-crosser, MC) is an asteroid whose orbit crosses that of Mars. Some Mars-crossers numbered below 100000 are listed here. They include the two numbered Mars trojans 5261 Eureka and . Many databases, for instance the JPL Small-Body Database (JPL SBDB), only list asteroids with a perihelion greater than 1.3 AU as Mars-crossers. An asteroid with a perihelion less than this is classed as a near-Earth object even though it is crossing the orbit of Mars as well as crossing (or coming near to) that of Earth. Nevertheless, these objects are listed on this page. A grazer is an object with a perihelion below the aphelion of Mars (1.67 AU) but above the Martian perihelion (1.38 AU). The JPL SBDB lists 13,500 Mars-crossing asteroids. Only 18 MCAs are brighter than absolute magnitude (H) 12.5, which typically makes these asteroids with H<12.5 more than 13 km in diameter depending on the |
Minimum Orbital Intersection Distance
Minimum orbit intersection distance (MOID) is a measure used in astronomy to assess potential close approaches and collision risks between astronomical objects. It is defined as the distance between the closest points of the osculating orbits of two bodies. Of greatest interest is the risk of a collision with Earth. Earth MOID is often listed on comet and asteroid databases such as the JPL Small-Body Database. MOID values are also defined with respect to other bodies as well: Jupiter MOID, Venus MOID and so on. An object is classified as a potentially hazardous object (PHO) – that is, posing a possible risk to Earth – if, among other conditions, its Earth MOID is less than 0.05 AU. For more massive bodies than Earth, there is a potentially notable close approach with a larger MOID; for instance, Jupiter MOIDs less than 1 AU are considered noteworthy since Jupiter is the most massive planet.Bruce Koehn,Minimum Orbital Intersection Distance, Lowell Observatory, retrieved o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
