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Information about Sub Brown Dwarf

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A size comparison between our Sun, a young sub-brown dwarf, and Jupiter. As the sub-brown dwarf ages, it will gradually cool and shrink.
Sub-brown dwarf is a planetary-mass object whose mass is smaller than the low-mass cut-off for brown dwarfs (around 13 times the mass of Jupiter). Unlike proper brown dwarfs, they are not massive enough to fuse deuterium. Therefore they are referred to as planets by some astronomers. Sub-brown dwarfs are formed in the manner of stars, through the collapse of a gas cloud, and not through accretion or core collapse from a circumstellar disc. The distinction between a sub-brown dwarf and a planet is unclear; astronomers are divided into two camps as whether to consider the formation process of a planet as part of its division in classification.[1]

An alternate definition involves the same mass range (less than a brown dwarf, but in the planetary range), but is free of gravitational attachment with any star. These are generally referred to as free-floating planets. Though less popular, this usage is in the IAU Extrasolar Planets provisional definition of a planet.[2]

List of suspected sub-brown dwarfs

See also

References

1. ^ What is a Planet? Debate Forces New Definition, by Robert Roy Britt, 02 November 2000
2. ^ Working Group on Extrasolar Planets - Defintion of a "Planet" POSITION STATEMENT ON THE DEFINITION OF A "PLANET" (IAU)
planet, as defined by the International Astronomical Union (IAU), is a celestial body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, not massive enough to cause thermonuclear fusion in its core, and has cleared its neighbouring region of
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Brown dwarfs are sub-stellar objects with a mass below that necessary to maintain hydrogen-burning nuclear fusion reactions in their cores, as do stars on the main sequence, but which have fully convective surfaces and interiors, with no chemical differentiation by depth.
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Jupiter  

This processed color image of Jupiter was produced in 1990 by the U.S. Geological Survey from a Voyager image captured in 1979. The colors have been enhanced to bring out detail.
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nuclear fusion is the process by which multiple atomic particles join together to form a heavier nucleus. It is accompanied by the release or absorption of energy. Iron and nickel nuclei have the largest binding energies per nucleon of all nuclei and therefore are the most stable.
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Deuterium, also called heavy hydrogen, is a stable isotope of hydrogen with a natural abundance in the oceans of Earth of approximately one atom in 6500 of hydrogen (~154 PPM). Deuterium thus accounts for approximately 0.015% (on a weight basis, 0.
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planet, as defined by the International Astronomical Union (IAU), is a celestial body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, not massive enough to cause thermonuclear fusion in its core, and has cleared its neighbouring region of
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STAR is an acronym for:

Organizations:
  • Society for Telescopy, Astronomy, and Radio, a non-profit astronomy club in New Jersey
  • Special Tasks and Rescue or Special Tactics and Response, synonyms for SWAT

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nebula (from Latin: "mist" [1] ; pl. nebulae or nebulæ, with ligature) is an interstellar cloud of dust, hydrogen gas and plasma. It is the first stage of a star's cycle.
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protoplanetary disk (or proplyd) is a rotating disk of dense gas surrounding a young newly formed star, a T Tauri star or Herbig star. The protoplanetary disk may be considered an accretion disk because gaseous material may be falling from the inner edge of the disk onto the
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Rogue Planet may refer to:

In literature:
  • Rogue Planet (Dan Dare), a Dan Dare story that ran in the original Eagle comic from Volume 6, Issue 48 to Volume 8, Issue 7
  • Rogue Planet (novel), a novel set in the Star Wars galaxy
In
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2M1207b is an extrasolar planet or natural satellite orbiting the brown dwarf 2M1207, in the constellation Centaurus 173 light years from Earth. Notable as one of the first extrasolar planets to be directly observed (by infrared imaging), it was discovered in September 2004 by the
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SCR 1845-6357 is a red dwarf star about 12.5 light-years away in the constellation Pavo. This star has a mass of about 7% of the Sun. However the measurements are still preliminary and are subject to change.
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Cha 110913-773444 (sometimes abbreviated Cha 110913) is an astronomical object surrounded by what appears to be a protoplanetary disk. There is no consensus yet among scientists whether to classify the object as a Sub-brown dwarf (with planets) or a rogue
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Planetar is a term used in astronomy that refers to one of two things:
  • Brown dwarfs - objects intermediate in size between planets and stars.
  • Interstellar planets - planetars that are cold masses smaller than brown dwarfs and do not orbit a star, but are free-floating

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Rogue Planet may refer to:

In literature:
  • Rogue Planet (Dan Dare), a Dan Dare story that ran in the original Eagle comic from Volume 6, Issue 48 to Volume 8, Issue 7
  • Rogue Planet (novel), a novel set in the Star Wars galaxy
In
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gas giant (sometimes also known as a Jovian planet after the planet Jupiter) is a large planet that is not primarily composed of rock or other solid matter. There are four gas giants in our Solar System; Jupiter, Saturn, Uranus, and Neptune.
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red dwarf star is a small and relatively cool star, of the main sequence, either late K or M spectral type. They constitute the vast majority of stars and have a mass of less than one-half that of the Sun (down to about 0.
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