  In near-infrared NaCo observations of the young brown dwarf 2MASS
J0041353-562112, we discovered a companion a little less than a magnitude
fainter than the primary. The binary candidate has a separation of 143 mas, the
spectral types are M6.5 and M9.0 for the two components. Colors and flux ratios
are consistent with the components being located at the same distance
minimizing the probability of the secondary being a background object. The
brown dwarf is known to show Li absorption constraining the age to less than
~200 Myr, and it was suspected to show ongoing accretion, indicating an age as
low as ~10 Myr. We estimate distance and orbital parameters of the binary as a
function of age. For an age of 10 Myr, the distance to the system is 50 pc, the
orbital period is 126 yr, and the masses of the components are ~30 and ~15
MJup. The binary brown dwarf fills a so far unoccupied region in the parameters
mass and age; it is a valuable new benchmark object for brown dwarf atmospheric
and evolutionary models.
