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Methanological Cycle
The climate of Titan, the largest moon of Saturn, is similar in many respects to that of Earth, despite having a far lower surface temperature. Its thick atmosphere, methane rain, and possible cryovolcanism create an analogue, though with different materials, to the climatic changes undergone by Earth during its far shorter year. Temperature Titan receives just about 1% of the amount of sunlight Earth does. The average surface temperature is about 90.6 K (-182.55 °C, or -296.59 °F). At this temperature water ice has an extremely low vapor pressure, so the atmosphere is nearly free of water vapor. However the methane in the atmosphere causes a substantial greenhouse effect which keeps the surface of Titan at a much higher temperature than what would otherwise be the thermal equilibrium. Haze in Titan's atmosphere contributes to an anti-greenhouse effect by reflecting sunlight back into space, making its surface significantly colder than its upper atmosphere. This ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titan Atmosphere Detail Narrow
Titan most often refers to: * Titan (moon), the largest moon of Saturn * Titans, a race of deities in Greek mythology Titan or Titans may also refer to: Arts and entertainment Fictional entities Fictional locations * Titan in fiction, fictionalized depictions of the moon of Saturn * Titan (Marvel Comics location), a moon ** Titan (Marvel Cinematic Universe), its Marvel Cinematic Universe counterpart * Titan, a moon in the list of locations of the DC Universe * Titan, a ''Fighting Fantasy'' gamebooks world Fictional characters * Titan (Dark Horse Comics), a superhero * Titan (Imperial Guard), a Marvel Comics superhero * Titan (New Gods), from DC Comics' ''Darkseid's Elite'' * Titan, in the Infershia Pantheon * Titan, in ''Megamind'' * Titan, in ''Sym-Bionic Titan'' * King Titan, on ''Stingray'' (1964 TV series) Fictional species and groups * Titan (''Dune'') * Titan (''Dungeons & Dragons'') * Teen Titans, a DC superhero team * Titan Legions, units in the tabletop game ''Ep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Equinox
A solar equinox is a moment in time when the Sun crosses the Earth's equator, which is to say, appears directly above the equator, rather than north or south of the equator. On the day of the equinox, the Sun appears to rise "due east" and set "due west". This occurs twice each year, around 20 March and 23 September. More precisely, an equinox is traditionally defined as the time when the plane of Earth's equator passes through the geometric center of the Sun's disk. Equivalently, this is the moment when Earth's rotation axis is directly perpendicular to the Sun-Earth line, tilting neither toward nor away from the Sun. In modern times, since the Moon (and to a lesser extent the planets) causes Earth's orbit to vary slightly from a perfect ellipse, the equinox is officially defined by the Sun's more regular ecliptic longitude rather than by its declination. The instants of the equinoxes are currently defined to be when the apparent geocentric longitude of the Sun is 0° a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intertropical Convergence Zone
The Intertropical Convergence Zone (ITCZ ), known by sailors as the doldrums or the calms because of its monotonous windless weather, is the area where the northeast and the southeast trade winds converge. It encircles Earth near the thermal equator though its specific position varies seasonally. When it lies near the geographic Equator, it is called the near-equatorial trough. Where the ITCZ is drawn into and merges with a monsoonal circulation, it is sometimes referred to as a monsoon trough, a usage that is more common in Australia and parts of Asia. Meteorology The ITCZ was originally identified from the 1920s to the 1940s as the ''Intertropical Front'' (''ITF''), but after the recognition in the 1940s and the 1950s of the significance of wind field convergence in tropical weather production, the term ''Intertropical Convergence Zone'' (''ITCZ'') was then applied. The ITCZ appears as a band of clouds, usually thunderstorms, that encircle the globe near the Equator. In the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hadley Cell
The Hadley cell, named after George Hadley, is a global-scale tropical atmospheric circulation that features air rising near the equator, flowing poleward at a height of 10 to 15 kilometers above the earth's surface, descending in the subtropics, and then returning equatorward near the surface. This circulation creates the trade winds, tropical rain-belts and hurricanes, subtropical deserts and the jet streams. A Hadley cell's relatively low-altitude overturning circulation has air sinking at roughly 30 degrees latitude after traveling from near the equator. Mechanism The driving force of atmospheric circulation is the uneven distribution of solar heating across the earth, which is greatest near the equator and least at the poles. The atmospheric circulation transports energy polewards, thus reducing the equator-to-pole temperature gradient. The mechanisms by which this is accomplished differ in tropical and extratropical latitudes. Hadley cells exist on either side of the equato ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cassini–Huygens
''Cassini–Huygens'' ( ), commonly called ''Cassini'', was a space research, space-research mission by NASA, the European Space Agency (ESA), and the Italian Space Agency (ASI) to send a space probe to study the planet Saturn and its system, including its Rings of Saturn, rings and Moons of Saturn, natural satellites. The Large Strategic Science Missions, Flagship-class robotic spacecraft comprised both NASA's ''Cassini'' space probe and ESA's Huygens (spacecraft), ''Huygens'' lander (spacecraft), lander, which landed on Saturn's largest moon, Titan (moon), Titan. ''Cassini'' was the fourth space probe to visit Saturn and the first to enter its orbit, where it stayed from 2004 to 2017. The two craft took their names from the astronomers Giovanni Domenico Cassini, Giovanni Cassini and Christiaan Huygens. Launched aboard a Titan IV, Titan IVB/Centaur on October 15, 1997, ''Cassini'' was active in space for nearly 20 years, with 13 years spent orbiting Saturn and studying the pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclones
In meteorology, a cyclone () is a large air mass that rotates around a strong center of low atmospheric pressure, counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere as viewed from above (opposite to an anticyclone). Cyclones are characterized by inward-spiraling winds that rotate about a zone of low pressure. The largest low-pressure systems are polar vortices and extratropical cyclones of the largest scale (the synoptic scale). Warm-core cyclones such as tropical cyclones and subtropical cyclones also lie within the synoptic scale. Mesocyclones, tornadoes, and dust devils lie within smaller mesoscale. Upper level cyclones can exist without the presence of a surface low, and can pinch off from the base of the tropical upper tropospheric trough during the summer months in the Northern Hemisphere. Cyclones have also been seen on extraterrestrial planets, such as Mars, Jupiter, and Neptune. Cyclogenesis is the process of cyclone formation and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rainbow
A rainbow is a meteorological phenomenon that is caused by reflection, refraction and dispersion of light in water droplets resulting in a spectrum of light appearing in the sky. It takes the form of a multicoloured circular arc. Rainbows caused by sunlight always appear in the section of sky directly opposite the Sun. Rainbows can be full circles. However, the observer normally sees only an arc formed by illuminated droplets above the ground, and centered on a line from the Sun to the observer's eye. In a primary rainbow, the arc shows red on the outer part and violet on the inner side. This rainbow is caused by light being refracted when entering a droplet of water, then reflected inside on the back of the droplet and refracted again when leaving it. In a double rainbow, a second arc is seen outside the primary arc, and has the order of its colours reversed, with red on the inner side of the arc. This is caused by the light being reflected twice on the inside of the drop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bulletin Of The American Astronomical Society
''Bulletin of the American Astronomical Society'' (''BAAS''; ''Bull. Am. Astron. Soc.'') is the journal of record for the American Astronomical Society established in 1969. It publishes meetings of the society, obituaries of its members, and scholarly articles. Four issues are published per year that are collected into a single volume. Articles are indexed, and often archived, from the Astrophysics Data System The SAO/NASA Astrophysics Data System (ADS) is an online database of over 16 million astronomy and physics papers from both peer reviewed and non-peer reviewed sources. Abstracts are available free online for almost all articles, and full scanned a ..., using the journal code BAAS. External links * Publications established in 1969 Astronomy journals English-language journals Quarterly journals American Astronomical Society academic journals {{astronomy-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tholin
Tholins (after the Greek (') "hazy" or "muddy"; from the ancient Greek word meaning "sepia ink") are a wide variety of organic compounds formed by solar ultraviolet or cosmic ray irradiation of simple carbon-containing compounds such as carbon dioxide (), methane () or ethane (), often in combination with nitrogen () or water ().Sarah Hörs"What in the world(s) are tholins?" Planetary Society, July 23, 2015. Retrieved 30 Nov 2016. Tholins are disordered polymer-like materials made of repeating chains of linked subunits and complex combinations of functional groups, typically nitriles and hydrocarbons and their degraded forms such as amines and phenyls. Tholins do not form naturally on modern-day Earth, but they are found in great abundance on the surfaces of icy bodies in the outer Solar System, and as reddish aerosols in the atmospheres of outer Solar System planets and moons. In the presence of water, tholins could be raw materials for prebiotic chemistry (i.e., the non-livin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Science Institute
The Space Science Institute (SSI) in Boulder, Colorado, is a nonprofit, public-benefit corporation formed in 1992. Its purpose is to create and maintain an environment where scientific research and education programs can flourish in an integrated fashion. SSI is among the four non-profit institutes in the US cited in a 2007 report by Nature, including Southwest Research Institute, Planetary Science Institute, and Eureka Scientific, which manage federal grants for non-tenure-track astronomers. Description SSI's research program encompasses the following areas: space physics, earth science, planetary science, and astrophysics. The flight operations branch manages the Cassini-Huygens spacecraft's visible camera instrument and provides spectacular images of Saturn and its moons and rings to the public. SSI participates in mission operations and is home to the Cassini Imaging Central Laboratory for OPerations (CICLOPS). The primary goal of SSI is to bring togeth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xanadu (Titan)
Xanadu (often called "Xanadu Region", though this is not its official name) is a highly reflective area on the leading hemisphere of Saturn's moon Titan. Its name comes from an alternate transcription of Shangdu, the summer capital of the Yuan dynasty established by Kublai Khan and made famous by Samuel Taylor Coleridge. The feature was first identified in 1994 by astronomers using the Hubble Space Telescope at infrared wavelengths, and has recently been imaged in more detail by the Cassini space probe. Xanadu is about the size of Australia. Preliminary observations indicate that Xanadu is a plateau-like region of highly reflective water ice, contrasting somewhat with the darker lower regions. These in turn seem to contrast quite sharply with the very dark maria, which were once believed to be seas of liquid hydrocarbons, but are now thought to be plains. Recent images by Cassini during encounters in October and December 2004 reveal complex albedo patterns in the western por ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
