Formation of Wide Binaries by Turbulent Fragmentation
  Understanding the formation of wide binary systems of very low mass stars (M
$\le$ 0.1 Msun) is challenging. The most obvious route is via widely separated
low-mass collapsing fragments produced through turbulent fragmentation of a
molecular core. However, close binaries/multiples from disk fragmentation can
also evolve to wide binaries over a few initial crossing times of the stellar
cluster through tidal evolution. Finding an isolated low mass wide binary
system in the earliest stage of formation, before tidal evolution could occur,
would prove that turbulent fragmentation is a viable mechanism for (very) low
mass wide binaries. Here we report high resolution ALMA observations of a known
wide-separation protostellar binary, showing that each component has a
circumstellar disk. The system is too young to have evolved from a close binary
and the disk axes are misaligned, providing strong support for the turbulent
fragmentation model. Masses of both stars are derived from the Keplerian
rotation of the disks; both are very low mass stars.
