2MASSJ12195156+3128497 (abbreviated to 2MASS J1219+3128) is a rapidly-rotating brown dwarf of spectral class L8, located in the constellation Coma Berenices
Tannock et al. (2021): 2MASS J04070752+1546457 – L3.5 spectral class brown dwarf with a period of 1.23±0.01 h 2MASSJ12195156+3128497 – L8 spectral class
south-east direction on the sky. 2MASSJ12195156+3128497 – L8 spectral class brown dwarf with a period of 1.14+0.03 −0.01 h 2MASS J03480772−6022270 – T7 spectral