This list of
extrasolar objects may and will change over time due to diverging measurements published between scientific journals, varying methods used to examine these objects, and the notably difficult task of discovering extrasolar objects in general. These objects are not stars, and are quite small on a universal or even stellar scale. Furthermore, these objects might be
brown dwarfs,
sub-brown dwarfs, or not even exist at all. Some data from the older sources may be unreliable due to the advancement of technology. Because of this, this list only cites the most certain measurements to date and is prone to change.
Maximum mass limitation Different space organisations have different maximum masses for exoplanets. The
NASA Exoplanet Archive (
NASA EA) states that an
object with a minimum mass lower than 30 , not being a
free-floating object, is qualified as an exoplanet.
Classification of Sub-brown Dwarf and Rogue Objects Sub-brown dwarfs are
formed in the manner of
stars, through the collapse of a
gas cloud (perhaps with the help of
photo-erosion) but have a
planetary mass, therefore are by definition below the
limiting mass for
thermonuclear fusion of
deuterium (~ ). Free-floating sub-brown dwarfs can be observationally indistinguishable from
rogue planets, which originally
formed around a star and were ejected from orbit. Similarly, a sub-brown dwarf formed free-floating in a star cluster may be captured into orbit around a star, making distinguishing sub-brown dwarfs and large planets also difficult. A definition for the term "sub-brown dwarf" was put forward by the
IAU Working Group on Extra-Solar Planets (IAU WGESP), which defined it as a free-floating body found in young star clusters below the
lower mass cut-off of brown dwarfs. == List==