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Carme Group
The Carme group is a group of retrograde and direct motion, retrograde irregular satellites of Jupiter that follow similar orbits to Carme (moon), Carme and are thought to have a common origin. Their semi-major axis, semi-major axes (distances from Jupiter) range between 22.9 and 24.1 gigametre, Gm, their orbital inclinations between 164.9° and 165.5°, and their eccentricity (orbit), orbital eccentricities between 0.23 and 0.27 (with one exception). The core members include (negative period indicates retrograde orbit): Scott S. Sheppard, David C. Jewitt, Carolyn Porco ''Jupiter's outer satellites and Trojans'', In: ''Jupiter. The planet, satellites and magnetosphere.'' Edited by Fran Bagenal, Timothy E. Dowling, William B. McKinnon. Cambridge planetary science, Vol. 1, Cambridge, UK: Cambridge University Press, , 2004, p. 263 – 28Full text(pdf). David Nesvorný, Cristian Beaugé, and Luke Dones ''Collisional Origin of Families of Irregular Satellites'', The Astronomical J ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retrograde And Direct Motion
Retrograde motion in astronomy is, in general, orbital or rotational motion of an object in the direction opposite the rotation of its primary, that is, the central object (right figure). It may also describe other motions such as precession or nutation of an object's rotational axis. Prograde or direct motion is more normal motion in the same direction as the primary rotates. However, "retrograde" and "prograde" can also refer to an object other than the primary if so described. The direction of rotation is determined by an inertial frame of reference, such as distant fixed stars. In the Solar System, the orbits around the Sun of all planets and most other objects, except many comets, are prograde. They orbit around the Sun in the same direction as the sun rotates about its axis, which is counterclockwise when observed from above the Sun's north pole. Except for Venus and Uranus, planetary rotations around their axes are also prograde. Most natural satellites have prograde orbi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chaldene (moon)
Chaldene , also known as , is a retrograde irregular satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard, in 2000, and given the temporary designation .MPEC 2001-A29: ''S/2000 J 7, S/2000 J 8, S/2000 J 9, S/2000 J 10, S/2000 J 11'' 2001 January 15 (discovery and ephemeris) Chaldene is about 3.8 kilometres in diameter, and orbits Jupiter at an average distance of 22,713,000 km in 759.88 days, at an of 167° to the ecliptic (169° to Jupiter's equator), in a retrograde direction and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around 1 millimeter (300 GHz) to the nominal red edge of the visible spectrum, around 700 nanometers (430 THz). Longer IR wavelengths (30 μm-100 μm) are sometimes included as part of the terahertz radiation range. Almost all black-body radiation from objects near room temperature is at infrared wavelengths. As a form of electromagnetic radiation, IR propagates energy and momentum, exerts radiation pressure, and has properties corresponding to both those of a wave and of a particle, the photon. It was long known that fires emit invisible heat; in 1681 the pioneering experimenter Edme Mariotte showed that glass, though transparent to sunlight, obstructed radiant heat. In 1800 the astronomer Sir William Herschel discovered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kaare Aksnes
Kaare Aksnes (born 25 March 1938 in Kvam in Hardanger) is a professor at the Institute for Theoretical Astrophysics at the University of Oslo. Personal life He was born in Kvam, Hordaland as a brother of the chemist Gunnar Aksnes. His parents were farmers. In 1959 he married teacher Liv Kristin Marøy. Career He finished his secondary education in 1956, and graduated with the cand.real. degree in 1963, having studied in both Bergen and Oslo. From 1964 to 1965 he was a research assistant at Harestua. He then worked in the United States for several years, and took the Ph.D. at Yale University in 1969. His doctor's thesis is today a standard work within estimating the course of planets, moons, meteors, comets and artificial sounds. His work is among other things used by NASA's Voyager sounds to Jupiter, and he received the NASA Group Achievement Award for his work. After several years at the Center for Astrophysics Harvard & Smithsonian in Cambridge, Massachusetts he returned fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Color Index
In astronomy, the color index is a simple numerical expression that determines the color of an object, which in the case of a star gives its temperature. The lower the color index, the more blue (or hotter) the object is. Conversely, the larger the color index, the more red (or cooler) the object is. This is a consequence of the logarithmic magnitude scale, in which brighter objects have smaller (more negative) magnitudes than dimmer ones. For comparison, the whitish Sun has a B−V index of , whereas the bluish Rigel has a B−V of −0.03 (its B magnitude is 0.09 and its V magnitude is 0.12, B−V = −0.03). Traditionally, the color index uses Vega as a zero point. To measure the index, one observes the magnitude of an object successively through two different filters, such as U and B, or B and V, where U is sensitive to ultraviolet rays, B is sensitive to blue light, and V is sensitive to visible (green-yellow) light (see also: UBV system). The set of passbands or filter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mean
There are several kinds of mean in mathematics, especially in statistics. Each mean serves to summarize a given group of data, often to better understand the overall value (magnitude and sign) of a given data set. For a data set, the ''arithmetic mean'', also known as "arithmetic average", is a measure of central tendency of a finite set of numbers: specifically, the sum of the values divided by the number of values. The arithmetic mean of a set of numbers ''x''1, ''x''2, ..., x''n'' is typically denoted using an overhead bar, \bar. If the data set were based on a series of observations obtained by sampling from a statistical population, the arithmetic mean is the ''sample mean'' (\bar) to distinguish it from the mean, or expected value, of the underlying distribution, the ''population mean'' (denoted \mu or \mu_x).Underhill, L.G.; Bradfield d. (1998) ''Introstat'', Juta and Company Ltd.p. 181/ref> Outside probability and statistics, a wide range of other notions of mean are o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Statistical Dispersion
In statistics, dispersion (also called variability, scatter, or spread) is the extent to which a Probability distribution, distribution is stretched or squeezed. Common examples of measures of statistical dispersion are the variance, standard deviation, and interquartile range. For instance, when the variance of data in a set is large, the data is widely scattered. On the other hand, when the variance is small, the data in the set is clustered. Dispersion is contrasted with location or central tendency, and together they are the most used properties of distributions. Measures A measure of statistical dispersion is a nonnegative real number that is zero if all the data are the same and increases as the data become more diverse. Most measures of dispersion have the same units of measurement, units as the quantity being measured. In other words, if the measurements are in metres or seconds, so is the measure of dispersion. Examples of dispersion measures include: * Standard deviat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Astronomical Union
The International Astronomical Union (IAU; french: link=yes, Union astronomique internationale, UAI) is a nongovernmental organisation with the objective of advancing astronomy in all aspects, including promoting astronomical research, outreach, education, and development through global cooperation. It was founded in 1919 and is based in Paris, France. The IAU is composed of individual members, who include both professional astronomers and junior scientists, and national members, such as professional associations, national societies, or academic institutions. Individual members are organised into divisions, committees, and working groups centered on particular subdisciplines, subjects, or initiatives. As of 2018, the Union had over 13,700 individual members, spanning 90 countries, and 82 national members. Among the key activities of the IAU is serving as a forum for scientific conferences. It sponsors nine annual symposia and holds a triannual General Assembly that sets policy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
S/2003 J 9
is a retrograde irregular satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2003. is about 1 kilometre in diameter, and orbits Jupiter at an average distance of in 767.60 days, at an inclination of 166.3° to the ecliptic (166° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.17. It belongs to the Carme group, made up of irregular retrograde moons orbiting Jupiter at a distance ranging between 23 and 24 Gm and at an inclination of about 165°. This moon was once considered lost Lost may refer to getting lost, or to: Geography *Lost, Aberdeenshire, a hamlet in Scotland * Lake Okeechobee Scenic Trail, or LOST, a hiking and cycling trail in Florida, US History *Abbreviation of lost work, any work which is known to have bee ... until November 2020, when the Minor Planet Center announced the recovery of S/2003 J 9 by Scott Sheppard in observations from September 2011 to Apr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pasithee (moon)
Pasithee , also known as , is a retrograde irregular satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2001, and given the temporary designation .MPEC 2002-J54: ''Eleven New Satellites of Jupiter'' May 15, 2002 (discovery and ephemeris) Pasithee is about 2 kilometres in diameter, and orbits Jupiter at an average distance of 23,307,000 km in 711.12 days, at an of 166° to the (164° to Jupiter's equator), in a [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kale (moon)
Kale , also known as , is a retrograde irregular satellite of Jupiter. It was discovered in 2001 by astronomers Scott S. Sheppard, D. Jewitt, and J. Kleyna, and was originally designated as .MPEC 2002-J54: ''Eleven New Satellites of Jupiter'' 2002 May (discovery and ephemeris) Kale is about in diameter, and orbits Jupiter at an average distance of in 736.55 days, at an of 165° to the (166° to Jupiter's equator), in a retrograde dire ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aitne (moon)
Aitne , also known as , is a retrograde irregular satellite of Jupiter. It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard, in 2001, and given the temporary designation . Aitne belongs to the Carme group, made up of irregular retrograde moons orbiting Jupiter at a distance ranging between 23 and 24 Gm and at an inclination of about 165°. Aitne is about 3 kilometres in diameter, and orbits Jupiter at an average distance of 22,285,000 km in 712.04 days, at an inclination of 166° to the ecliptic (164° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.393. It was named in August 2003 2003 August (naming the moon) after Aitna or Aitne, the divine personification of [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
