WISE J2209+2711

WISE J2209+2711 (WISE J220905.73+271143.9) is a brown dwarf of spectral type Y0:,^[1] located in constellation Pegasus at 22 light-years from Earth.^[6] Its discovery was published in 2014 by Cushing et al.^[1]

WISE J220905.73+271143.9

WISE J2209+2711 Credit: unWISE
Observation data Epoch J2000      Equinox J2000
Constellation	Pegasus
Right ascension	22h 09m 05.734s
Declination	+27° 11′ 44.00″
Characteristics
Evolutionary stage	brown dwarf
Spectral type	Y0[1]
Astrometry
Proper motion (μ)	RA: 1204.40 ±2.14 mas/yr[2] Dec.: –1362.08 ±1.34 mas/yr[2]
Parallax (π)	161.7±2.0 mas[3]
Distance	20.2 ± 0.2 ly (6.18 ± 0.08 pc)
Details
Mass	5[4] MJup
Radius	1.03±0.01 or 1.13±0.01[5] RJup
Luminosity	10−6.82±0.03[5] L☉
Surface gravity (log g)	4.0[4] cgs
Temperature	350[4] K
Age	800[4] Myr
Other designations
WISE J220905.73+271143.9[1]
Database references
SIMBAD	data
WISE J2209+2711 Location of WISE J2209+2711 in the constellation Pegasus

Physical properties

WISE J2209+2711 is one of a few Y-dwarfs observed with JWST NIRSpec and MIRI. The modelling re-produced the spectrum with an excellent fit using phosphine-free and diabatic models. The excellent fit was achieved with a model that used an effective temperature of 350 K and a surface gravity of 4.0. This corresponds to a 5 M_J object with an age of 800 Myrs.^[4]

See also

• List of star systems within 20–25 light years
• List of Y-dwarfs