WISE 2220−3628

WISE J222055.31−362817.4 (designation abbreviated to WISE 2220−3628) is a brown dwarf of spectral class Y0,^[1] located in constellation Grus at approximately 34.2 light-years from Earth.^[4]

WISE J222055.31−362817.4

WISE 2220-3628 Credit: NASA/ESA/CSA JWST MIRI
Observation data Epoch J2000[1]      Equinox J2000[1]
Constellation	Grus
Right ascension	22h 20m 55.31s[1]
Declination	−36° 28′ 17.4″[1]
Characteristics
Spectral type	Y0[1]
Apparent magnitude (J (MKO-NIR filter system))	20.38 ± 0.17[1]
Apparent magnitude (H (MKO-NIR filter system))	20.81 ± 0.30[1]
Astrometry
Radial velocity (Rv)	−53.2±2.8[2] km/s
Total velocity	55.33±2.82[2] km/s
Proper motion (μ)	RA: 288.92 ±0.15 mas/yr[3] Dec.: −97.10 ±0.16 mas/yr[3]
Parallax (π)	93.50±1.02 mas[3]
Distance	34.9 ± 0.4 ly (10.7 ± 0.1 pc)
Details
Mass	6-35[2] MJup
Radius	0.94±0.14[2] RJup
Surface gravity (log g)	4.7±0.5[2] cgs
Temperature	480±41[2] K
Age	4.5±4.0[2] Gyr
Other designations
WISE J222055.31−362817.4,[1] WISE 2220−3628[1]
Database references
SIMBAD	data

Discovery

WISE 2220−3628 was discovered in 2012 by J. Davy Kirkpatrick et al. from data, collected by Wide-field Infrared Survey Explorer (WISE) Earth-orbiting satellite—NASA infrared-wavelength 40 cm (16 in) space telescope, which mission lasted from December 2009 to February 2011. In 2012 Kirkpatrick et al. published a paper in The Astrophysical Journal, where they presented discovery of seven new found by WISE brown dwarfs of spectral type Y, among which also was WISE 2220−3628.^[1]

Properties

Y-class dwarfs are among the coldest of all brown dwarfs.^[1] WISE 2220-3628 was observed with JWST and found to be very similar to CWISEP J1935-1546, with the difference of having no signature of an aurora and no temperature inversion in its atmosphere.^[2]

Distance

The most accurate distance estimate of WISE 2220−3628 was a trigonometric parallax, published in 2014 by Beichman et al.: 0.136 ± 0.017 arcsec, corresponding to a distance of 7.4 ± 0.9 pc (24.1 ± 2.9 ly).^[5] Later the parallax measurement was improved revealing a larger distance of about 34 light years.^[4]

See also

• List of star systems within 30–35 light-years
• List of Y-dwarfs
• WISE 0146+4234 (Y0)
• WISE 0350−5658 (Y1)
• WISE 0359−5401 (Y0)
• WISE 0535−7500 (≥Y1)
• WISE 0713−2917 (Y0)
• WISE 0734−7157 (Y0)