Program: GS-2015B-FT-5

We have discovered one of the brightest and least massive free-floating "planets." Possibly only 7-13 Myr old, given tentative association with the TW Hydrae young moving group, the L7 dwarf 2MASS J11193254-1137466 is estimated to be only 5-7 times the mass of Jupiter. At J=17.2 mag and Ks=14.6 mag, it is also the brightest, and hence most readily characterizable extrasolar planetary-mass object in this mass range. We seek one hour of FLAMINGOS-2 R~450 spectroscopy to determine the surface gravity, and hence the cooling age of this young brown dwarf. The proposed observations will improve on our current SNR~5-7 GNIRS spectrum, which asserts the object's youth, but is inconclusive about its actual surface gravity and age.