Red dwarfs: the immortal entities of the universe

Red dwarfs are small-sized stars of around 0.2 solar masses that burn by converting their hydrogen to helium through nuclear fusion. The rate of burning is so slow that their estimated life span is of the order of trillions of years. 

Since our universe is just 13.8 billion years old it has not seen the death of any red dwarf. Proxima Centauri, the nearest star to the sun is a red dwarf. How amazing is that!!

In fact, fifty out of the sixty closest stars are all red dwarfs. Due to their low luminosity, they are not easily visible. Interestingly not a single red dwarf is visible from Earth with the naked eye. Red dwarfs along with being the smallest kind of star in the main sequence are also the coolest kind. The coolest red dwarfs can have temperatures around 2000 K. The smallest red dwarfs can have radii around 9% of that of the sun with a mass around 7.5% of the solar mass.

by

Prabir Rudra