Week of Dec. 23-29, 2018
Many years ago, a friend was taking a basic astronomy course to fulfill her science requirements at a major university. She was doing quite well, in fact. She could cite the distances of all the planets, describe the expansion of the universe and even explain how stars are born and die.
One evening, we were discussing the stages that some stars experience on their way toward death, the red giant and supergiant phases. I mentioned the bright star Betelgeuse in the constellation Orion, perhaps the most famous of all red supergiant stars, and asked if she had ever seen it.
Her puzzled look and response startled me. "You mean you can actually see a red supergiant?" she replied.
There she was, filled with all this esoteric astronomical knowledge, and no one had ever bothered to take her out at night to see one for herself.
Betelgeuse shines brightly in the northeastern corner of Orion; it represents the shoulder the great hunter, and you can see it glowing brightly low in the eastern sky after dark this week. Its unusual name comes from the Arabic term "Ibt al-Jauzah," meaning "armpit of the Central One," not surprising considering its location within the hunter's outline.
With about 15 to 20 times more mass than our sun, Betelgeuse is one of the first ever to have its size measured. And it's big — very big. While we could align 109 Earths across the face of our sun, we would need at least 700 suns to cross the face of Betelgeuse.
Indeed, Betelgeuse is so immense that if it were to replace our sun at the center of our planetary system, the star would engulf the orbits of Mercury, Venus, Earth and Mars and stretch part of the way to Jupiter! Yet it appears as a point of light in our night sky because of its great distance from us — some 520 light-years away, or about 3,100 trillion miles.
Betelgeuse remains one of the largest stars known, though its size fluctuates by as much as 60 percent as it shudders and pulsates.
Astronomers agree that Betelgeuse is nearing the end of its life, and that it will soon erupt in a violent supernova explosion. But "soon" is a word that means something different to astronomers than to most people. Betelgeuse may erupt a few thousand or tens of thousands of years from now. And when it explodes, it will surely produce one of the most dramatic celestial displays that stargazers have ever seen from our planet.
Such a supernova would temporarily produce more than a billion times more power than our sun. Sounds terrifying, until we realize that its great distance would weaken its brilliance in our sky to about that of Venus.
An explosive Betelgeuse would inspire people to go outside and look up at the heavens, many for the first time, to see one of nature's great sky shows. And that wouldn't be such a bad thing.
So never mind all this exotic astronomical data. ... Get out under the dark night sky to see this remarkable superstar for yourself!
Visit Dennis Mammana at dennismammana.com. To read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.
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