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Ring 4 (ring Of Uranus)
The rings of Uranus are intermediate in complexity between the more extensive set around Saturn and the simpler systems around Jupiter and Neptune. The rings of Uranus were discovered on March 10, 1977, by James L. Elliot, Edward W. Dunham, and Jessica Mink. William Herschel had also reported observing rings in 1789; modern astronomers are divided on whether he could have seen them, as they are very dark and faint.(re study by Stuart Eves) By 1977, nine distinct rings were identified. Two additional rings were discovered in 1986 in images taken by the ''Voyager 2'' spacecraft, and two outer rings were found in 2003–2005 in Hubble Space Telescope photos. In the order of increasing distance from the planet the 13 known rings are designated 1986U2R/ζ, 6, 5, 4, α, β, η, γ, δ, λ, ε, ν and μ. Their radii range from about 38,000 km for the 1986U2R/ζ ring to about 98,000 km for the μ ring. Additional faint dust bands and incomplete arcs may exist between the ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uranian Rings Scheme
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Uranian may refer to: __NOTOC__ Sexuality *Uranian (sexology), a historical term for homosexual men *Uranians, a group of male homosexual poets Astronomy *Uranian, of or pertaining to the planet Uranus *Uranian system, refers to the 27 moons of Uranus Mythology and fiction *Uranian, relating to Aphrodite Urania, an epithet of the Greek goddess Aphrodite *Uranian, relating to Urania, the muse of astronomy *Uranian (comics), a fictional race in the Marvel Universe Other uses *Uranian Phalanstery, artist collectives in New York City *For ''Uranian astrology'' see Hamburg School of Astrology See also *Urania (other) *Uranus (other) Uranus is a planet in the Solar System. Uranus may also refer to: *Uranus (mythology), an ancient Greek sky god Fiction * ''Uranus'' (novel), a 1948 novel by Marcel Aymé *Uranus, a character in ''Duckman ''Duckman: Private Dick/Family Man' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophelia (moon)
Ophelia is a moon of Uranus. It was discovered from the images taken by ''Voyager 2'' on January 20, 1986, and was given the temporary designation S/1986 U 8. It was not seen until the Hubble Space Telescope recovered it in 2003. Ophelia was named after the daughter of Polonius, Ophelia, in William Shakespeare's play ''Hamlet''. It is also designated Uranus VII. Other than its orbit, radius of 21 km and geometric albedo of 0.08 virtually nothing is known about it. At the Voyager 2 images Ophelia appears as an elongated object, the major axis pointing towards Uranus. The ratio of axes of the Ophelia's prolate spheroid is 0.7 ± 0.3. Ophelia acts as the outer shepherd satellite for Uranus' ε ring. The orbit of Ophelia is within the synchronous orbit radius of Uranus, and is therefore slowly decaying due to tidal forces. See also * Moons of Uranus References Explanatory notes Citations External links Ophelia ProfilebNASA's Solar System Explorati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geometric Albedo
In astronomy, the geometric albedo of a celestial body is the ratio of its actual brightness as seen from the light source (i.e. at zero phase angle) to that of an ''idealized'' flat, fully reflecting, diffusively scattering ( Lambertian) disk with the same cross-section. (This phase angle refers to the direction of the light paths and is not a phase angle in its normal meaning in optics or electronics.) Diffuse scattering implies that radiation is reflected isotropically with no memory of the location of the incident light source. Zero phase angle corresponds to looking along the direction of illumination. For Earth-bound observers, this occurs when the body in question is at opposition and on the ecliptic. The visual geometric albedo refers to the geometric albedo quantity when accounting for only electromagnetic radiation in the visible spectrum. Airless bodies The surface materials (regoliths) of airless bodies (in fact, the majority of bodies in the Solar System) are stro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azimuth
An azimuth (; from ar, اَلسُّمُوت, as-sumūt, the directions) is an angular measurement in a spherical coordinate system. More specifically, it is the horizontal angle from a cardinal direction, most commonly north. Mathematically, the relative position vector from an observer (origin) to a point of interest is projected perpendicularly onto a reference plane (the horizontal plane); the angle between the projected vector and a reference vector on the reference plane is called the azimuth. When used as a celestial coordinate, the azimuth is the horizontal direction of a star or other astronomical object in the sky. The star is the point of interest, the reference plane is the local area (e.g. a circular area with a 5 km radius at sea level) around an observer on Earth's surface, and the reference vector points to true north. The azimuth is the angle between the north vector and the star's vector on the horizontal plane. Azimuth is usually measured in d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phase Angle (astronomy)
Phase angle in astronomical observations is the angle between the light incident onto an observed object and the light reflected from the object. In the context of astronomical observations, this is usually the angle Sun-object-observer. For terrestrial observations, "Sun–object–Earth" is often nearly the same thing as "Sun–object–observer", since the difference depends on the parallax, which in the case of observations of the Moon can be as much as 1°, or two full Moon diameters. With the development of space travel, as well as in hypothetical observations from other points in space, the notion of phase angle became independent of Sun and Earth. The etymology of the term is related to the notion of planetary phases, since the brightness of an object and its appearance as a "phase" is the function of the phase angle. The phase angle varies from 0° to 180°. The value of 0° corresponds to the position where the illuminator, the observer, and the object are collinear, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dust
Dust is made of fine particles of solid matter. On Earth, it generally consists of particles in the atmosphere that come from various sources such as soil lifted by wind (an aeolian process), volcanic eruptions, and pollution. Dust in homes is composed of about 20–50% dead skin cells. The rest, and in offices, and other human environments is composed of small amounts of plant pollen, human hairs, animal fur, textile fibers, paper fibers, minerals from outdoor soil, burnt meteorite particles, and many other materials which may be found in the local environment. Atmospheric Atmospheric or wind-borne fugitive dust, also known as ''aeolian dust'', comes from arid and dry regions where high velocity winds are able to remove mostly silt-sized material, deflating susceptible surfaces. This includes areas where grazing, ploughing, vehicle use, and other human behaviors have further destabilized the land, though not all source areas have been largely affected by anthropogenic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uranian Rings PIA01977
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Uranian may refer to: __NOTOC__ Sexuality *Uranian (sexology), a historical term for homosexual men *Uranians, a group of male homosexual poets Astronomy *Uranian, of or pertaining to the planet Uranus *Uranian system, refers to the 27 moons of Uranus Mythology and fiction *Uranian, relating to Aphrodite Urania, an epithet of the Greek goddess Aphrodite *Uranian, relating to Urania, the muse of astronomy *Uranian (comics), a fictional race in the Marvel Universe Other uses *Uranian Phalanstery, artist collectives in New York City *For ''Uranian astrology'' see Hamburg School of Astrology See also *Urania (other) *Uranus (other) Uranus is a planet in the Solar System. Uranus may also refer to: *Uranus (mythology), an ancient Greek sky god Fiction * ''Uranus'' (novel), a 1948 novel by Marcel Aymé *Uranus, a character in ''Duckman ''Duckman: Private Dick/Family Man' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mab (moon)
Mab, or Uranus XXVI, is an inner satellite of Uranus. It was discovered by Mark R. Showalter and Jack J. Lissauer in 2003 using the Hubble Space Telescope. It was named after Queen Mab, a fairy queen from English folklore who is mentioned in William Shakespeare's play ''Romeo and Juliet''. Because the moon is small and dark, it was not seen in the heavily scrutinized images taken by ''Voyager 2'' during its Uranus flyby in 1986. However, it is brighter than another moon, Perdita, which was discovered from Voyager's photos in 1997. This led scientists to re-examine the old photos again, and the satellite was finally found in the images. The size of Mab is not known exactly. If it is as dark as Puck, it is about 24 km in diameter. On the other hand, if it is brightly coloured like the neighbouring moon Miranda, it would be even smaller than Cupid and comparable to the smallest outer satellites. Mab is heavily perturbed. The actual source for perturbation is still unclear, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Celestial Body Atmosphere
An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A stellar atmosphere is the outer region of a star, which includes the layers above the opaque photosphere; stars of low temperature might have outer atmospheres containing compound molecules. The atmosphere of Earth is composed of nitrogen (78%), oxygen (21%), argon (0.9%), carbon dioxide (0.04%) and trace gases. Most organisms use oxygen for respiration; lightning and bacteria perform nitrogen fixation to produce ammonia that is used to make nucleotides and amino acids; plants, algae, and cyanobacteria use carbon dioxide for photosynthesis. The layered composition of the atmosphere minimises the harmful effects of sunlight, ultraviolet radiation, the solar wind, and cosmic rays to protect organisms from genetic damage. The current compositi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Occultation
An occultation is an event that occurs when one object is hidden from the observer by another object that passes between them. The term is often used in astronomy, but can also refer to any situation in which an object in the foreground blocks from view (occults) an object in the background. In this general sense, occultation applies to the visual scene observed from low-flying aircraft (or computer-generated imagery) when foreground objects obscure distant objects dynamically, as the scene changes over time. If the closer body does not entirely conceal the farther one, the event is called a ''transit''. Both transit and occultation may be referred to generally as ''occlusion''; and if a shadow is cast onto the observer, it is called an eclipse. The symbol for an occultation, and especially a solar eclipse, is file:Occultation symbol.svg (U+1F775 🝵). Occultations by the Moon The term occultation is most frequently used to describe lunar occultations, those relativ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serendipity
Serendipity is an unplanned fortunate discovery. Serendipity is a common occurrence throughout the history of product invention and scientific discovery. Etymology The first noted use of "serendipity" was by Horace Walpole on 28 January 1754. In a letter he wrote to his friend Horace Mann, Walpole explained an unexpected discovery he had made about a lost painting of Bianca Cappello by Giorgio Vasari by reference to a Persian fairy tale, ''The Three Princes of Serendip''. The princes, he told his correspondent, were "always making discoveries, by accidents and sagacity, of things which they were not in quest of." The name comes from ''Serendip'', an old Persian name for Sri Lanka (Ceylon), hence ''Sarandib'' by Arab traders. It is derived from the Sanskrit ''Siṃhaladvīpaḥ'' (Siṃhalaḥ, Sri Lanka + dvīpaḥ, island). The word has been exported into many other languages, with the general meaning of "unexpected discovery" or "fortunate chance". Applications Inventio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kuiper Airborne Observatory
The Gerard P. Kuiper Airborne Observatory (KAO) was a national facility operated by NASA to support research in infrared astronomy. The observation platform was a highly modified Lockheed C-141A Starlifter jet transport aircraft (s/n: 6110, registration: N714NA, callsign: NASA 714) with a range of 6,000 nautical miles (11,000 km), capable of conducting research operations at altitudes of up to 48,000 feet (14 km). Aircraft The KAO was based at the Ames Research Center, NAS Moffett Field, near Sunnyvale, California. Prior to its conversion to the airborne observatory, it had served as Lockheed's demonstrator for a potential civilian version of the C-141. Though it began operation in 1974 as a replacement for an earlier aircraft, the Galileo Observatory (itself a converted Convair 990 (N711NA) that was destroyed in a collision with a U.S. Navy Lockheed P-3C Orion patrol aircraft in 1973), the KAO wasn't dedicated until May 21, 1975. The KAO flew at altitudes of 41,000 t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
