The Life of a Star: Red Supergiants

How does a star become a red supergiant? Find out on today's episode of Astro Minute!

What is Astro Minute?

Welcome to the Astro Minute! I'm Lauren Smyth, and with the help of astronomer and teacher Kelli Smyth, I'll be your tour guide as we explore the secrets of the night sky sixty seconds at a time.

Welcome to the Astro Minute, where we’re exploring the universe sixty seconds at a time. I’m Lauren Smyth, and today we’re looking at the old age of high-mass stars.

When stars with more than eight times the sun’s mass leave the main sequence, things begin to get really exciting. When the core of a high-mass star runs out of hydrogen, it collapses and heats up until helium fusion ignites within it, which then ignites hydrogen fusion in the shell of gas around the core, causing the star’s outer gas to expand, just like lower mass stars. But because of their extra mass, high-mass stars expand up to fifteen hundred times the diameter of our sun, passing even Saturn’s orbit, making them the largest stars by volume in the universe. We call these red supergiants.

Look for these magnificent red supergiants: Antares in Scorpio and Betelgeuse in Orion.

I’m Lauren Smyth, and that’s your AstroMinute.