Key facts
- Category
- Stars
- Object class
- Red supergiant star
- Mass
- ~15–20 solar masses
- Temperature
- ~3,600 K surface
- Scale fact
- 1.05 billion kmdiameter
- Estimated age
- ~8–14 million years
- Composition
- Hydrogen and helium
Betelgeuse
1.05 billion kmdiameter
Visual creditscaleofspace.org / CC BY-NC 4.0
Details
Betelgeuse is a red supergiant nearing the end of its stellar life. Its dramatic dimming in 2019 and 2020 turned out to be caused by a dusty veil ejected from the star, giving astronomers a rare direct look at how giant stars shed material into space.
Betelgeuse is a red supergiant whose extended atmosphere pulsates, forms large convective cells and loses material to space. Its diameter varies with wavelength and time, so the value on this scale represents an approximate photospheric size rather than a fixed solid boundary.
During the Great Dimming of 2019–2020, part of the star’s surface cooled after a mass-ejection event and newly formed dust obscured some of its light. The episode was evidence of active mass loss, not a sign that a supernova was imminent.
Links
- Editorial guides
- Universe journey
- Solar neighborhood
- Preset views
- Wikipedia
- Betelgeuse on Wikipedia
Size neighbors
Objects near Betelgeuse on the scale
On the logarithmic size axis, Betelgeuse falls between Eta Carinae A and Stephenson 2 DFK 49. The band uses nearby Stars records.
Shared physical scale
2.29billion km
Sources
References for Betelgeuse
Measurements and descriptive context are compiled by the Scale of Space team from the references below. If you find an error, please let us know.
- Betelgeuse — Wikipedia
- Visual: scaleofspace.org / CC BY-NC 4.0
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About
Scale of Space is a scroll-based journey through the universe, placing objects on a single logarithmic scale so you can compare size across an unbroken range.
Guides explain selected parts of that range, while focused views filter the objects by subject.