Sub-brown dwarf

From Wikipedia, the free encyclopedia

Sub-brown dwarfs or brown sub-dwarfs are objects only faintly visible in large telescopes

• Their inferred masses are smaller than the low-mass cut-off for brown dwarfs.
• They are colder than stars undergoing nuclear fusion.

Their status is somewhere between giant planets and proper stars, but they are referred to as planets by some astronomers.

However, a sub-brown dwarf is 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.

Contents 1 List of suspected sub-brown dwarfs 2 See also 3 External links 4 References

[edit] List of suspected sub-brown dwarfs

• 2M1207b
• SCR 1845-6357 B
• Cha 110913-773444

[edit] See also

• planetar (astronomy)
• interstellar planetary mass object
• brown dwarf
• supergiant planet
• giant planet

[edit] External links

• Working Group on Extrasolar Planets - Defintion of a "Planet" POSITION STATEMENT ON THE DEFINITION OF A "PLANET" (IAU)

[edit] References