Brown dwarfs differ from stars largely due to their mass. They lack the mass to ignite internally and shine brightly. However, they are believed to arise like stars, out of thick clouds of gas and dust that collapse under their own weight. And like stars, brown dwarfs develop disks of gas and dust that circle around them.
FUSE has detected a hot companion star to Eta Carinae, one of the most massive stars in our Milky Way galaxy.