Unravelling the mystery of brown dwarfs

Brown dwarfs are astronomical objects with masses between those of planets and stars. The question of where exactly the limits of their mass lie remains a matter of debate, especially since their constitution is very similar to that of low-mass stars. So how do we know whether we are dealing with a brown dwarf or a very low mass star?

source https://www.sciencedaily.com/releases/2021/08/210827082409.htm