# Betelgeuse losing brightness

**URL:** <https://boards.straightdope.com/t/betelgeuse-losing-brightness/845478>\
**Category:** Factual Questions\
**Created:** [December 27, 2019, 11:34pm UTC](https://boards.straightdope.com/t/betelgeuse-losing-brightness/845478 "2019-12-27T23:34:54Z")\
**Posts on this page:** 1\
**Showing post:** 200

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**Author:** ![Northern\_Piper](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/northern_piper/32/5304_2.png) [@Northern\_Piper](https://boards.straightdope.com/u/Northern_Piper)\
**Post date:** [July 22, 2025, 12:52pm UTC](https://boards.straightdope.com/t/betelgeuse-losing-brightness/845478/200 "2025-07-22T12:52:14Z")

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Astronomers say they have found Betelgeuse’s small companion: a blue A or B star, hot but not yet on the main sequence, orbiting Betelgeuse at about 4 AU. Believed to be the explanation for the six year dimming cycle, caused as it orbits Betelgeuse.

> **[Betelgeuse’s companion star revealed in new images](https://www.sciencenews.org/article/betelgeuse-companion-star-revealed)**
>
> Revealed by advanced imaging, the long-sought "Betelbuddy" is much smaller and fainter than Betelgeuse and orbits within the supergiant’s atmosphere.

> **[Astronomers crack 1,000-year-old Betelgeuse mystery with 1st-ever sighting of...](https://www.space.com/astronomy/astronomers-crack-1-000-year-old-betelgeuse-mystery-with-1st-ever-sighting-of-secret-companion-photo-video)**
>
> "Papers that predicted Betelgeuse's companion believed that no one would likely ever be able to image it."

> **[It's official. Betelgeuse has a companion star. But it won't last long – one...](https://www.skyatnightmagazine.com/news/betelgeuse-companion-star)**
>
> Betelgeuse's companion star was found in a tight orbit using the ‘Alopeke instrument on Gemini North at the International Gemini Observatory.

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