---
title: "Betelgeuse: facts, distance and size – Krillion Space"
description: "Betelgeuse is a huge, cool red supergiant marking a shoulder of Orion and the closest star of its kind to Earth. Size, distance and sourced facts."
url: https://krilion.app/atlas/betelgeuse
language: en-US
---

# Betelgeuse

Red supergiant. Depth 31 on the Krillion Space voyage, in the Milky Way.

Betelgeuse is a huge, cool red supergiant marking a shoulder of Orion and the closest star of its kind to Earth. It is near the end of its short life and will someday explode as a supernova, and in recent years it surprised astronomers with a dramatic dimming and the probable detection of a close companion star.

![Betelgeuse at depth 31 in Krillion Space, painted by the game (an illustration, not a photograph).](https://krilion.app/assets/atlas/betelgeuse.webp)

## Fact sheet

- **Type:** Red supergiant (semiregular variable star)
- **Distance:** Roughly 550 light-years from the Sun (estimates range from about 500 to 720)
- **Size:** Roughly 700 to 760 times the Sun's radius and about 15 to 19 times its mass
- **Constellation:** Orion
- **Position in the sky:** Right ascension 5h 55m, declination +7° 25′
- **Seeing it from Earth:** Easy to see with the naked eye from almost everywhere as the orange-red star at Orion's shoulder, best in the evening sky from about December to March (northern winter, southern summer).
- **On the voyage:** Depth 31, in the Milky Way section of the route, between the Pleiades and the Orion Nebula

## Things to know

- If Betelgeuse took the Sun's place, its surface would reach beyond the orbit of Jupiter. ([NASA](https://science.nasa.gov/universe/what-is-betelgeuse-inside-the-strange-volatile-star/))
- Starting in late 2019, Betelgeuse lost about 60% of its brightness within a few months, then recovered by April 2020, an episode called the Great Dimming. ([NASA](https://science.nasa.gov/universe/what-is-betelgeuse-inside-the-strange-volatile-star/))
- Hubble and other observatories traced the dimming to a huge eruption from the star's surface that cooled into a light-blocking dust cloud with several times the mass of our Moon. ([NASA](https://science.nasa.gov/missions/hubble/hubble-sees-red-supergiant-star-betelgeuse-slowly-recovering-after-blowing-its-top))
- In 2025 astronomers using the 'Alopeke camera on Gemini North reported a probable faint companion star of about 1.5 solar masses orbiting only about four Earth-Sun distances from Betelgeuse's surface; it has been nicknamed Siwarha and should be easiest to check again in November 2027. ([NOIRLab](https://noirlab.edu/public/news/noirlab2523/))
- Although it is only about 10 million years old, Betelgeuse is expected to explode as a supernova in about 100,000 years, leaving a neutron star or black hole. ([NASA](https://science.nasa.gov/universe/what-is-betelgeuse-inside-the-strange-volatile-star/))

## Sources

- [NASA Science – What Is Betelgeuse? Inside the Strange, Volatile Star](https://science.nasa.gov/universe/what-is-betelgeuse-inside-the-strange-volatile-star/)
- [NASA Science (Hubble) – Hubble Sees Red Supergiant Star Betelgeuse Slowly Recovering After Blowing Its Top](https://science.nasa.gov/missions/hubble/hubble-sees-red-supergiant-star-betelgeuse-slowly-recovering-after-blowing-its-top)
- [NOIRLab – Gemini North Discovers Long-Predicted Stellar Companion of Betelgeuse (noirlab2523)](https://noirlab.edu/public/news/noirlab2523/)
- [Joyce et al. 2020, ApJ – New mass and distance estimates for Betelgeuse (arXiv)](https://arxiv.org/abs/2006.09837)

## On the route

- Previous landmark: [Pleiades](https://krilion.app/atlas/pleiades)
- Next landmark: [Orion Nebula](https://krilion.app/atlas/orion-nebula)
- [The whole Star Atlas](https://krilion.app/atlas)
- [Fly the voyage yourself](https://krilion.app/d/): every right answer warps your ship one stop deeper.