Facts about Betelgeuse

1. 08

   Red supergiants like Betelgeuse eject massive stellar winds carrying roughly one million times more material per year than our Sun loses, creating the expanding nebula surrounding the star.

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2. 07

   Betelgeuse's iron core is thought to be approximately the size of Earth but with a mass comparable to our Sun, making it extraordinarily dense before the star's inevitable supernova explosion.

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3. 06

   Betelgeuse's variable brightness cycles through a primary period of approximately 2,140 days, causing its magnitude to fluctuate by up to one full magnitude over several years.

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4. 05

   In 1920, Albert Michelson used interferometry to measure Betelgeuse's angular diameter, making it the first star besides the Sun to have its size directly measured.

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5. 04

   Approximately 640 light-years away, Betelgeuse will eventually explode as a supernova, potentially becoming as bright as the full moon despite its vast distance from Earth.

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6. 03

   Betelgeuse's surface temperature of approximately 3,500 Kelvin makes it significantly cooler than our Sun's 5,778 Kelvin, which contributes to its distinctive red color.

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7. 02

   Betelgeuse's radius spans approximately 700 times larger than our Sun, making it one of the largest known stars in the Milky Way galaxy.

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8. 01

   During its 2019-2020 dimming event, Betelgeuse lost approximately 40 percent of its brightness over several months.

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