A Faded Star

By Dennis Mammana

January 23, 2020 4 min read

Week of Jan. 26 - Feb. 1, 2020

If you've been stargazing at all recently, you may have noticed the great constellation Orion hovering in the southeastern sky after dark, with its rectangular form and three central stars in a nearly straight line. You may also have noticed something a bit odd about it — but you can't quite say what it is.

Back in the fall, when I first saw Orion after six months of it being below the horizon, I noticed it, too. The star at its northeasternmost corner — Betelgeuse — seemed much fainter than I remembered it. It still is.

If you don't believe it, check it out. What once was the tenth brightest star in the heavens has oddly faded to 21st place!

Glowing with an obvious reddish-orange hue, Betelgeuse is one of the best-known red supergiant stars in the sky. With about 12 times more mass than our sun, Betelgeuse is one of the first stars ever to have its size measured.

And it's big. Very big. We could align 109 Earths across the face of our sun, but it would require nearly 800 suns to cross the face of Betelgeuse. Yet, the star appears as a mere pinpoint in our night sky because of its great distance from us- - at least 600 light-years, or about 3,600 trillion miles.

Astronomers agree that Betelgeuse is nearing the end of its life. It shudders and pulsates; we have watched its subtle dimming and brightening over many years and believe that it will soon erupt in a violent supernova explosion.

So, when the star began to fade significantly last October, stargazers were all abuzz. Is this it? Is a supernova imminent?

The fact is, we really don't know when this will happen. You see, when astronomers say it will erupt "soon," we're talking about 100,000 years or so, at the earliest.

Or tomorrow. We just don't know.

This unusual fading, however, could mean any number of things. Perhaps several of its dimming cycles have coincidentally aligned at their minimum points and now cause the star to appear noticeably fainter as a result. Or perhaps there was some eruption of gas or dust from the star that dims it temporarily. At this point, we just don't know.

So what if you should go outdoors one night and find that Betelgeuse is illuminating the sky as a brilliant supernova explosion? Is this something to worry about here on Earth?

A Betelgeuse supernova would temporarily produce more than a billion times more power than our sun and, even at its great distance, the star would shine as brightly as a full moon!

But we won't need to worry about dangerous radiation coming from the explosion. A supernova would need to be some 25 times closer before it could affect life on Earth.

Sadly, what an explosive Betelgeuse would do is change the appearance of Orion — and the night sky — forever. But it would also teach us so much about the end-of-life stages of stars and would inspire folks to go outside to look up at the night sky, many for the first time in their lives.

And that wouldn't be such a bad thing!

 Betelgeuse is one of the best-known red supergiant stars in the sky.
Betelgeuse is one of the best-known red supergiant stars in the sky.

Visit Dennis Mammana at facebook.com/DennisMammana. To read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.

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