Brown dwarf stars, are not actually stars at all as they do not have enough mass for hydrogen fusion. However, they also aren’t planets, as they are too massive, so what exactly are brown dwarf stars?
It turns out they are “Brown Dwarfs”, it’s a classification that was made specifically to describe the phenomenon where a body has gathered so much material that it is much too massive to be considered a planet, but has not enough to achieve hydrogen fusion.
A regular star achieves a balance between its vast gravity forces pulling inwards and trying to collapse itself, versus the outward forces generated by the process of fusion. This delicate balance maintains the size of the star, generates heat and light and give it its classification.
As brown dwarfs are much cooler and not emitting vast amounts of light like a star, they are very hard to detect and find in space, especially at larger distances. Fortunately, they are very common, and this means we have detected a large number despite the difficulties.
Professional and citizen astronomers have worked together to create a three dimensional space map of brown dwarf stars within 65 light-years using the Backyards Worlds: Planet 9 platform.
Enjoy this stunning 3D visualization in the below video, which provides an excellent way to demonstrate just how common Brown Dwarf stars are in our Universe.