Hubble Finds Brown Dwarf Binaries Rare

A new Hubble survey, focusing on some of the coldest, lowest-mass brown dwarfs in our solar neighborhood, has yielded a surprising result. Binary companions, once thought to be relatively common among these objects, are proving to be exceedingly rare.
Binary pairs were frequently observed, suggesting that the star formation process does indeed produce brown dwarf binaries. So, where are all the companions going? The new findings indicate that these youthful pairings are likely short-lived.
The weak gravitational bonds between widely separated brown dwarfs are easily disrupted by the gravitational tug of passing stars.