WISE 0825+2805

WISE 0825+2805 (WISE J082507.35+280548.5) is a (sub-)brown dwarf with a spectral type of Y0.5. It is about 21.4 light-years away from Earth in the Cancer constellation.

Discovery
WISE 0825+2805 was discovered in 2015 by Schneider et al. with the Wide-field Infrared Survey Explorer and the Hubble Space Telescope, using WFC3 near-infrared grism spectroscopy. The team also announced the discovery of three T-dwarfs as well as two additional Y-dwarfs (WISE J1206+8401 and WISE J2354+0240) in the same paper.

Physical properties
WISE 0825+2805 was observed with JWST NIRCam and MIRI. The modeling requires phosphine-free and diabatic models to produce a good fit. The good fit requires an effective temperature of 350 Kelvin and a surface gravity of log g = 4.0. Alternatively a lower surface gravity could improve the fit. The model parameters correspond to a mass of and an age of 800 Myrs.