Editing Brown dwarf (section)

=== Brown dwarfs around stars ===
{{Main|Brown-dwarf desert}}
Brown dwarfs and massive planets in a close orbit (less than 5 au) around stars are rare and this is sometimes described as the brown dwarf desert. Less than 1% of stars with the mass of the sun have a brown dwarf within 3–5 au.<ref>{{cite journal |last1=Grether |first1=Daniel |last2=Lineweaver |first2=Charles H. |date=2006-04-01 |title=How Dry is the Brown Dwarf Desert? Quantifying the Relative Number of Planets, Brown Dwarfs, and Stellar Companions around Nearby Sun-like Stars |url=https://ui.adsabs.harvard.edu/abs/2006ApJ...640.1051G |journal=The Astrophysical Journal |volume=640 |issue=2 |pages=1051–1062 |doi=10.1086/500161 |arxiv=astro-ph/0412356 |bibcode=2006ApJ...640.1051G |s2cid=8563521 |issn=0004-637X}}</ref>

An example for a star–brown dwarf binary is the first discovered T-dwarf [[Gliese 229|Gliese 229 B]], which orbits around the main-sequence star Gliese 229 A, a red dwarf. Brown dwarfs orbiting [[subgiant]]s are also known, such as [[TOI-1994b]] which orbits its star every 4.03 days.<ref>{{cite journal |last1=Page |first1=Emma |last2=Pepper |first2=Joshua |last3=Kane |first3=Stephen |last4=Zhou |first4=George |last5=Addison |first5=Brett |last6=Wright |first6=Duncan |last7=Wittenmyer |first7=Robert |last8=Johnson |first8=Marshall |last9=Evans |first9=Philip |last10=Collins |first10=Karen |last11=Hellier |first11=Coel |last12=Jensen |first12=Eric |last13=Stassun |first13=Keivan |last14=Rodriguez |first14=Joseph |date=2022-06-01 |title=TOI-1994b: An Eccentric Brown Dwarf Transiting a Subgiant |journal=American Astronomical Society Meeting Abstracts |url=https://ui.adsabs.harvard.edu/abs/2022AAS...24030521P |volume=54 |issue=6 |pages=305.21|bibcode=2022AAS...24030521P }}</ref>

There is also disagreement if some low-mass brown dwarfs should be considered planets. The [[NASA Exoplanet Archive|NASA Exoplanet archive]] includes brown dwarfs with a minimum mass less or equal to 30 Jupiter masses as planets as long as there are other criteria fulfilled (e.g. orbiting a star).<ref>{{cite web |title=Exoplanet Criteria for Inclusion in the Exoplanet Archive |url=https://exoplanetarchive.ipac.caltech.edu/docs/exoplanet_criteria.html |access-date=2023-04-16 |website=exoplanetarchive.ipac.caltech.edu}}</ref> The Working Group on Extrasolar Planets (WGESP) of the [[International Astronomical Union|IAU]] on the other hand only considers planets with a mass below 13 Jupiter masses.<ref>{{cite web |title=Working Group on Extrasolar Planets |url=https://w.astro.berkeley.edu/~basri/defineplanet/IAU-WGExSP.htm |access-date=2023-04-16 |website=w.astro.berkeley.edu}}</ref>