Discovery of a Late L Dwarf: WISEP J060738.65+242953.4

Abstract: We discover a late-type L dwarf, WISEP J060738.65+242953.4 (W0607+2429), by comparing the Wide-field Infrared Survey Explorer (WISE) preliminary data release to the Two Micron All Sky Survey (2MASS) in search of high proper motion objects (>0.3" yr^-1). W0607+2429 was found to have a proper motion of 0.57 +/- 0.02" yr^-1. Based on colors and color-color diagrams using 2MASS and Sloan Digital Sky Survey (SDSS) photometry, we estimate the spectral type (optical) to be L8 within a spectral sub-type. Based on the spectral type estimated we find W0607+2429 to have a distance of 7.8^+1.4_(-1.2) pc, making it one of only four very-late L dwarfs within 10 pc, and the third closest L dwarf overall. This close L/T transition dwarf will play a pivotal role in resolving outstanding issues of condensate clouds of low temperature atmospheres.