Unique Facts about Red Dwarfs, Faint Stars That Can Live for Trillions of Years – Space

SPACE — Red dwarf stars are the largest population of stars in the galaxy. However, this star is too faint to be seen with the naked eye from Earth.

The faint light means that this type of star has a longer lifetime than the sun.

Scientists think that 20 of the 30 stars near Earth are red dwarfs. The star closest to the Sun, Proxima Centauri, is a red dwarf star.

What exactly is a red dwarf? According to astronomer Michaël Gillon of the University of Liège in Belgium there is no exact definition of a red dwarf.

Red dwarfs form like other main sequence stars. First, clouds of dust and gas are attracted by gravity and begin to rotate. The material then clumps in the center, and when it reaches a critical temperature, fusion begins.

Little Star

Red dwarfs are among the smallest stars, weighing between 7.5 percent and 50 percent the mass of the Sun. Its smaller size means the burning temperature is lower, only reaching 3,500 degrees Celsius.

For comparison, the sun has a temperature of 5,500 C. The low temperature of red dwarfs means that this type is much dimmer than stars like the Sun.

Its low temperature also means that the star burns through its hydrogen supply more quickly. Meanwhile, other more massive stars only burn hydrogen in their cores before reaching the end of their lifetime.

A red dwarf consumes all its hydrogen, inside and outside its core. This extends the lifespan of red dwarfs by trillions of years. This age far exceeds the lifetime of sun-like stars, which are usually 10 billion years old.

Red dwarfs are similar to brown dwarfs

Scientists sometimes have difficulty distinguishing between red dwarf stars and brown dwarf stars. Brown dwarfs are cool and dim, and likely formed in the same way as red dwarfs.

However, brown dwarfs never reach the fusion point because they are too small, so they are not considered stars. Brown dwarfs are often considered failed stars.

To find out whether a celestial body is a brown or red dwarf, scientists measure the temperature of the object’s atmosphere. The temperature of a fusion-free brown dwarf is cooler than 2,000 Kelvin or 1,727 C.