Kuiper Belt Objects. Area of the Solar System beyond the planets, comprising small bodies The Kuiper belt is named in honor of the Dutch astronomer Gerard Kuiper, who conjectured the existence of a similar belt in 1951.[10] However, it was not until 1980 that the astronomer Julio Angel Fernandez published a paper suggesting the existence of a comet belt beyond Neptune,[11][12] which could serve as a source for short-period comets. Although the Kuiper belt is named after Gerard Kuiper, Fernandez was the researcher who first predicted its existence.[13][14] The Kuiper belt is distinct from the hypothesized Oort cloud, which is believed to be a thousand times more distant and mostly spherical. History[edit] After the discovery of Pluto in 1930, many speculated that it might not be alone.
The region now called the Kuiper belt was hypothesized in various forms for decades. Hypotheses[edit] The first astronomer to suggest the existence of a trans-Neptunian population was Frederick C. Discovery[edit] Name[edit] Scattered Disc Objects. Although the closest scattered-disc objects approach the Sun at about 30–35 AU, their orbits can extend well beyond 100 AU. This makes scattered objects among the most distant and coldest objects in the Solar System.[1] The innermost portion of the scattered disc overlaps with a torus-shaped region of orbiting objects traditionally called the Kuiper belt,[2] but its outer limits reach much farther away from the Sun and farther above and below the ecliptic than the Kuiper belt proper. [a] Discovery[edit] Traditionally, devices like a blink comparator were used in astronomy to detect objects in the Solar System, because these objects would move between two exposures—this involved time-consuming steps like exposing and developing photographic plates or films, and people then using a blink comparator to manually detect prospective objects.
Subdivisions of trans-Neptunian space[edit] Scattered disc versus Kuiper belt[edit] Detached objects[edit] An alternative classification, introduced by B. Oort Cloud Objects. An artist's rendering of the Oort cloud and the Kuiper belt (inset). Sizes of individual objects have been exaggerated for visibility. The Oort cloud /ˈɔrt/[1] (named after the Dutch astronomer Jan Oort), or Öpik–Oort cloud,[2] is a hypothesized spherical cloud of predominantly icy planetesimals that may lie roughly 50,000 AU, or nearly a light-year, from the Sun.[3] This places the cloud at nearly a quarter of the distance to Proxima Centauri, the nearest star to the Sun. The Kuiper belt and the scattered disc, the other two reservoirs of trans-Neptunian objects, are less than one thousandth of the Oort cloud's distance.
The outer limit of the Oort cloud defines the cosmographical boundary of the Solar System and the region of the Sun's gravitational dominance.[4] The Oort cloud is thought to comprise two separate regions: a spherical outer Oort cloud and a disc-shaped inner Oort cloud, or Hills cloud. Hypothesis[edit] Structure and composition[edit] Origin[edit] In June 2010 Harold F. Trans-Neptunian Objects. A trans-Neptunian object (TNO; also written transneptunian object) is any minor planet in the Solar System that orbits the Sun at a greater average distance (semi-major axis) than Neptune. The first trans-Neptunian object to be discovered was Pluto in 1930. It took until 1992 to discover a second trans-Neptunian object orbiting the Sun directly, (15760) 1992 QB1. Now over 1,200 trans-Neptunian objects appear on the Minor Planet Center's List Of Transneptunian Objects.[1] As of November 2009, two hundred of these have their orbits well-enough determined that they have been given a permanent minor planet designation.[2][3] History[edit] Discovery of Pluto[edit] The orbit of each of the planets is slightly affected by the gravitational influences of the other planets.
Pluto was easiest to find because it has the highest apparent magnitude of all known trans-Neptunian objects. Discovery of other trans-Neptunian objects[edit] Distribution and classification[edit] Physical characteristics[edit] Cis-Neptunian objects. Centaurs orbit the Sun between Jupiter and Neptune, often crossing the orbits of the large gas giant planets. There is an emerging sense[2] that the centaurs may simply be objects similar to scattered disc objects that were knocked inwards from the Kuiper belt rather than outwards, making them cis-Neptunian rather than trans-Neptunian scattered-disc objects. Notes[edit] References[edit] Jupiter. Structure Jupiter is composed primarily of gaseous and liquid matter. It is the largest of four gas giants as well as the largest planet in the Solar System with a diameter of 142,984 km (88,846 mi) at its equator. The density of Jupiter, 1.326 g/cm3, is the second highest of the gas giants, but lower than for any of the four terrestrial planets.
Composition Jupiter's upper atmosphere is composed of about 88–92% hydrogen and 8–12% helium by percent volume or fraction of gas molecules. Since a helium atom has about four times as much mass as a hydrogen atom, the composition changes when described as the proportion of mass contributed by different atoms. Based on spectroscopy, Saturn is thought to be similar in composition to Jupiter, but the other gas giants Uranus and Neptune have relatively much less hydrogen and helium.[21] Because of the lack of atmospheric entry probes, high-quality abundance numbers of the heavier elements are lacking for the outer planets beyond Jupiter. Mass. Jupiter loses a stripe - space - 11 May 2010. Jupiter has lost one of its prominent stripes, leaving its southern half looking unusually blank. Scientists are not sure what triggered the disappearance of the band. Jupiter's appearance is usually dominated by two dark bands in its atmosphere – one in the northern hemisphere and one in the southern hemisphere.
But recent images taken by amateur astronomers show that the southern band – called the south equatorial belt – has disappeared. The band was present at the end of 2009, right before Jupiter moved too close to the sun in the sky to be observed from Earth. When the planet emerged from the sun's glare again in early April, its south equatorial belt was nowhere to be seen. No cover This is not the first time the south equatorial belt has disappeared.
According to this theory, the south equatorial belt disappears when whitish clouds form on top of it, blocking our view of the darker clouds. More From New Scientist Lose weight by tricking body into thinking it's cold (New Scientist) How will Jupiter hold up his pants? | Bad Astronomy | Discover M. From Emily at The Planetary Society blog comes word that one of Jupiter’s belts has disappeared… again. This image, by the accomplished amateur astronomer Anthony Wesley, shows what’s up. Usually, the Great Red Spot is accompanied by a dark reddish belt that goes all the way around the planet, like the one in the northern hemisphere you can see in the picture. However, the Southern Equatorial Belt, as it’s called, is gone! This has happened before, in fact. It’s not clear exactly why this sort of thing occurs, though. The belts (and their lighter-colored cousins, called zones) are weather patterns that stretch around the planet, a bit like the jet stream on Earth.
Jupiter is a weird place. But there is a very cool thing about this: you can see it for yourself! But if you prefer your astronomy to be virtual, you can check out other pictures at Wesley’s site, as well as Astro Bob’s blog. I wonder how long the belt will be gone?