Groombridge 1618

The star GJ 380 is a later orange main sequence star of spectral type K8 V. It is located in the constellation Ursa Major, is about 15 light years away to the perigee stars.

Properties

The star has about 67 % of the solar mass, 60 % of the solar radius and the surface temperature is only 4000 K. Thus, it glows orange - red. This star has only about 4.6 % of the solar luminosity. GJ 380 is a flare star, but compared to other flare stars, he is very bright strong. It has a rotation speed of about 2.8 km / s

It is thought that GJ 380 has a planet, but its existence is not assured.

Energy production and further development

GJ 380 is one of the main sequence stars, which generate their energy through the proton-proton chain. It converts at its core hydrogen to helium and is relatively stable. Since the star has only 67 % of the solar mass, it is much longer on the main sequence relax as the sun; while the sun lingers on the main sequence for about 10 billion years it will be 380 about 25 billion years at GJ. After that he will reach a core temperature of about 100 million degrees Celsius and the helium burning in the core will then begin; in the outer layers of hydrogen burning. The star swells up into a red giant. Since GJ 380 has more than 0.5 solar masses, the star is able to produce helium by the triple alpha process. Later, when the star has exhausted its helium, it will repel its outer layers as a planetary nebula, leaving behind a white dwarf, which then cools to a black dwarf.

Swell

• Individual star fifth size and darker
• Big Dipper
• Star catalog Gliese Jahreiß