Illustration of brown dwarfs, strange objects that are somewhere between a regular star and a planet in size, orbiting each other NASA, ESA, and A. Feild (STScI)
A tiny star and its companion, a “failed star” known as a brown dwarf, are locked in an incredibly tight orbit, rotating in a volume smaller than the sun.
Unless a star has collapsed into a white dwarf or a neutron star, it can only shrink its orbit around another object through a process called magnetic braking, where stellar winds strip away material and carry away momentum. However, it was unclear whether this…