Betelgeuse is 900 times larger than our sun and astronomers think it's about to explode. What if Earth orbited this giant monster of a star?

Betelgeuse, Betelgeuse, Betelgeuse. Unlike in the movie, you don’t have to say it three times to make it appear, just look up!

Betelgeuse is one of the ten brightest stars in the sky, and on a clear night, you’ll notice its distinctly reddish tint.

But while it may be bigger and brighter than our Sun, could Betelgeuse replace our Sun? What if Earth orbited this red supergiant?

The reason why we’re able to see Betelgeuse so clearly from 640 light years away, is because it’s massive. In fact, it’s 12-20 times more massive than our Sun! Betelgeuse also takes up about 900 times more space than our Sun currently does, and it’s 100,000 times brighter!

Oddly enough, despite its size, Betelgeuse is actually cooler than our sun. A quick guide to stars: their temperature determines their color.

If they’re red, they’re colder; about 3,000 degrees Kelvin. Blue stars are the hottest, reaching temperatures higher than 30,000 degrees Kelvin! But yellow seems to be just right; like our own Sun, which is 6,000 degrees Kelvin.

So even though Betelgeuse outshines our own Sun, could we count on it to make life on Earth a little cooler? No.

Let’s get this straight. Betelgeuse isn’t just a little bigger than our sun, it’s 900 times bigger! Supergiants are the largest stars in our universe! So can you imagine what putting one in the center of our Solar System would do?

First, say goodbye to Mercury, Venus, Earth and Mars. Betelgeuse is so big, that if it replaced the sun, it would instantly engulf the inner planets, and its surface would extend beyond Mars, maybe even as far as Saturn.

As a pulsating star, Betelgeuse’s diameter fluctuates periodically. So even beyond its surface area our planet is not safe.

Betelgeuse is always losing mass, expelling huge plumes of gas. If Betelgeuse were in our Sun’s position, this blown-off matter would reach as far as Neptune!

But, you know, we haven’t given this WHAT IF a fair chance. Saying you’d die instantly is kind of a cop out. So let’s imagine that Betelgeuse was a safe enough distance from Earth that it could provide enough heat and light for us, the same way our Sun does today.

Well, you’d live a normal life, and then die of old age… before your first birthday. That’s because it would take more than 300 years for our planet to orbit Betelgeuse just once! Happy returns! Or not…

So the next time you look up at the stars and point out Betelgeuse, be glad that you can see it at a safe distance. And don’t take it for granted! Betelgeuse is predicted to blow up soon.

In fact, it might’ve already happened. When the light from its explosion eventually reaches us, whether its tomorrow or 100,000 years from now, it’ll be the brightest supernova in human history! Its light might even rival the moon’s! But hey, at least it won’t actually be that close, or else we’d be gone.

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