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Betelgeuse – Star · Red supergiant
Image: ALMA (ESO/NAOJ/NRAO)/E. O’Gorman/P. Kervella · CC BY 4.0
⭐ Stars · The Stars

Betelgeuse

Star · Red supergiant

Betelgeuse is a red supergiant in Orion’s shoulder. If it replaced our Sun, it would swallow Mercury, Venus, Earth and Mars. It is near the end of its life and will one day explode as a supernova.

  • 550 light-years awayEven light – the fastest thing there is – needs 550 years to get here.
  • ~700 × SunSize
  • OrionConstellation
🔭 Find it in the sky

Take a closer look

A bubbling surface

Betelgeuse is so huge that big telescopes can see its surface as more than a dot. It isn’t a smooth ball: it is lumpy and changing, with a few gigantic bubbles of hot gas – each one bigger than our whole Sun – rising and sinking like soup boiling on a stove.

Young but nearly done

Betelgeuse is only about 10 million years old – the Sun is 4.6 billion years old. Big stars burn through their fuel incredibly fast, so even though Betelgeuse is young, it is already near the end of its life. The Sun will keep shining for billions of years more.

Made of star stuff

When Betelgeuse explodes, it will scatter carbon, oxygen, iron and other elements into space. Long ago, exploding stars did the same for the cloud that formed our Solar System. The iron in your blood and the calcium in your bones were made inside stars.

How we found out

  1. Medieval times

    Its name comes from Arabic and is often translated as “the hand of al-Jawzāʾ”, a figure in the sky.

  2. 1920

    Albert Michelson and Francis Pease make Betelgeuse the first star (other than the Sun) to have its size measured.

  3. 2019–20

    The “Great Dimming”: Betelgeuse fades noticeably. Astronomers find it puffed out a cloud of dust that blocked some of its light.

  4. 2025

    Astronomers report the first glimpse of a small companion star orbiting it.

🤔 Something to wonder about

If Betelgeuse exploded 500 years ago, would we know?

See it yourself

The bright orange-red star at Orion’s upper-left shoulder (as seen from the Northern Hemisphere).

Got it?

Mark Betelgeuse as explored to earn 10 XP.