WISE 1541−2250 (full designation WISEPA J154151.66−225025.2) is a sub-brown or brown dwarf of spectral class Y0.5,[2] located in the constellation Libra at approximately 18.6 light-years from Earth.

[5] This object received popular attention when its discovery was announced in 2011 at a distance estimated to be only about 9 light-years, which would have made it the closest brown dwarf known.

[6] (For really close brown dwarfs see, for example, Luhman 16, WISE 1506+7027, Epsilon Indi Ba, Bb, or UGPS 0722-05).

[5] For several months after its discovery, before the publication of its parallax by Kirkpatrick et al. in 2012,[2] WISE 1541−2250 was considered to be the nearest known brown dwarf at approximately 9 light-years from the Sun, and the seventh-nearest of all star systems, at slightly more than twice the distance of the nearest known star system Alpha Centauri.

This view existed because of a very rough preliminary parallax with a baseline of 1.2 years, published in the discovery paper: 0.351 ± 0.108 arcsec, corresponding to a distance 2.8+1.3−0.6 pc, or 9.3+4.1−2.2 ly.