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Our sun is big. It’s 864,000 miles or 1,392,000 km in diameter. Or 109x wider than Earth. But it’s also an average sized star.

Some stars are much bigger.

Betelgeuse, in the constellation Orion, is a red supergiant star ~700x the size of the sun.

If we replaced our sun with Betelgeuse, it would stretch past Jupiter's orbit. https://universe.nasa.gov/news/237/what-is-betelgeuse-inside-the-strange-volatile-star/ #space #science

in reply to Sheril Kirshenbaum

- Seems like a bad idea to me, but I’m no scientist! 🤷🏽‍♂️
in reply to Sheril Kirshenbaum

Wonderful and miraculous! And some say there is no Creator. 🤔
in reply to Sheril Kirshenbaum

Jawdropping. Thanks for posting and injecting a bit of stellar awe into the afternoon.
in reply to Sheril Kirshenbaum

I stopped calling our Sun an “average” star when I learned that something like 75% of stars are red dwarfs. It’s in the middle, size-wise, but it’s large compared to a large majority of stars.

It also bothered me that red dwarfs got the shaft in texts (early high school) that I taught out of - they barely rated a mention in descriptions of properties and life cycles of stars.

in reply to Sheril Kirshenbaum

I'm impressed by the size of Betelgeuse, thanks for sharing this 🙂
in reply to Sheril Kirshenbaum

🥥 Thank you for this star information, Sheril.
Now please, nobody say Betelgeuse 3 times. Thank you. 🥥
in reply to Sheril Kirshenbaum

i vote for UY Scuti or better Stephenson 2-18 😁
This entry was edited (1 year ago)
in reply to Sheril Kirshenbaum

<writing note to myself> Don't replace sun with Betelgeuse!
in reply to Sheril Kirshenbaum

Thanks for starting this, Sheril… stellar evolution is a favourite topic of mine 😄

Just remembered another cool factoid. While Betelgeuse is huge, it's only ~10x the mass of our Sun, give or take. That means the average density of Betelgeuse is about a *millionth* the density of air at Earth's sea level – It's been nicknamed a "red hot vacuum” 🤯

That said, the *core* is still very dense and hot, enough to carry on nuclear fusion for a little while longer!

in reply to Sheril Kirshenbaum

I learned in college that VY Canis Majoris would go out to Saturn's orbit

"Betelgeuse" is a cooler name though 🙂

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