If that sounds as if the supply should therefore soon exhaust itself, just remember that the sun is a star nearly a million miles across.

Our sun converts around 600 million tons of hydrogen into helium every second. And stars don’t have an infinite supply of hydrogen. But nuclear fusion in stars at first requires hydrogen. It’s this process that causes our sun to radiate light, heat and other forms of energy as a byproduct. Stars radiate energy by converting hydrogen to helium via nuclear fusion. They create a bow shock as the star moves through space. The multiple arcs around the star are due to winds from Betelgeuse crashing against the surrounding interstellar medium. This 2013 far-infrared image, from the Herschel space observatory, shows the star and its enigmatic surroundings. It’s also the nearest red supergiant star to Earth. One of the best known red giant stars is the old red star Betelgeuse. But what processes will drive the sun’s evolution to the red giant stage? And what will happen exactly, inside the star, as it changes? Let’s examine the fate of low- or intermediate-mass stars such as our sun, as they evolve to the red giant phase. So it’s our sun’s destiny to become a red giant star (and afterwards a white dwarf, and then a black dwarf). So you can see that our sun is one of the stars that will inevitably, someday, become a red giant. Astronomers call such stars low- or intermediate-mass stars.

To become a red giant, a particular star must have between half our sun’s mass, and eight times our times our sun’s mass. Please donate what you can to our annual crowd-funding campaign. Interested in stars? Help EarthSky bring them to you. They’ll end their lives as a so-called black dwarf: a tiny, burned-out, virtually-invisible cinder.

Eventually, after billions of years, these stars will become totally cold and radiate no energy. Then the star will slowly contract and cool to become a white dwarf: Earth-sized, ultra-dense star corpses radiating a tiny fraction of their original energy. Once at the red giant stage, a star might stay that way for up to a billion years. It has slowly swollen up to many times its original size. What are red giants?Ī red giant is a star in its death stages. Image via NASA Goddard Space Flight Center/ Chris Smith (KBRwyle). Artist’s concept of the evolved stars known as red giants, at different distances in this illustration.

What is red giant universe