Fomalhaut

From Freepedia

Image:Fomalhaut ring hst 2004.jpg Fomalhaut (α PsA / α Piscis Austrini / Alpha Piscis Austrini) is the brightest star in the constellation Piscis Austrinus and one of the brightest stars in the nighttime sky. Its name means "mouth of the whale", from the Arabic فم الحوت fum al-ħūt. It is a class A star on the main sequence approximately 25 light-years (7.688 parsecs) from Earth.

A first-magnitude star, Fomalhaut was, until about March 2000, farther from any other first-magnitude star in the celestial sphere than any other first-magnitude star in the sky (along with Archernar. That honour now belongs to Antares in the constellation of Scorpius, whose nearest 1st magnitude star, Alpha Centauri is moving away from Antares as seen in the celestial sphere.

Fomalhaut is believed to be a young star, only 200 to 300 million years old, with a potential lifespan of only a billion years. The surface temperature of the star is around 8500 kelvins. Compared to the Sun, its mass is about 2.3, its luminosity is about 15, and its diameter is roughly 1.7.

It is surrounded by a disk of dust in a toroidal shape with a very sharp inner edge at a radial distance of 133 AU, inclined 24 degrees from edge-on. The dust is distributed in a belt about 25 AU wide; the geometric centre of the disk is offset by about 15 AU from Fomelhaut. The disk is sometimes referred to as "Fomalhaut's Kuiper belt".

Fomalhaut's disk is believed to be protoplanetary, and emits considerable infrared radiation. A planet, designated Fomalhaut b, has been inferred from analysis of the dust cloud in 1998.

Over history there have been a large number of variations on the star's name. It was first identified in pre-history and there is archaeological evidence that it was part of rituals in 2500s BCE in Persia where it would have been one of the Persians' four "royal stars". In the religion of Stregheria, Fomalhaut is a fallen angel and quarter guardian of the northern gate.

1 Fomalhaut in fiction and popular culture
2 Trivia
3 References
4 External links

Fomalhaut in fiction and popular culture

In fiction, Fomalhaut 3 is the homeworld of the Dorsai, a group featured in a large body of work initially created by the author Gordon R. Dickson. It is also the location of a major space station, Alverez Station, in orbit about the planet Fomalhaut V (called America by the colonists) in the science fiction Roleplaying game FTL:2448 by Tri Tac Games.

The image shown on this page bears a striking resemblence to the Eye of Sauron, as noted by New Scientist magazine and other mainstream publications. However, the concentric rings around Fomalhaut on the picture from Hubble are artefacts from the coronagraph. These artefacts make the image similar to the Eye of Sauron. But without these artefacts, Fomalhaut system is only a single star surrounded by a dust ring.