Astronomy, Astrophysics and Space Science

Stars, Cool Dwarfs, Brown Dwarfs

Brown dwarfs are substances which are too big to be called planets and too minor to be stars. They have crowds that range between twice the mass of Jupiter and the lower mass limit for nuclear reactions. An ultra-cool dwarf is a stellar or sub-stellar object of spectral class M that has an effective temperature under 2,700 K. TRAPPIST-1 is a widely known example of an ultra-cool dwarf star. Stars are enormous celestial bodies made mostly of hydrogen and helium that produce light and heat from the mixing nuclear forges inside their cores. Aside from our sun, the dots of bright we see in the sky are all light-years from Earth.