Is a Spectacular Stellar Explosion About to Light Up Our Skies?
Updated: Jan 20, 2020
The last time a massive star, a supergiant, exploded in spectacular fashion in our galaxy was in 1604. In recent months, one of the most famous and brightest stars in the night sky began behaving in a strange way. The strange behavior could be the precursor of the star exploding as a supernova.
If you look toward the east in the evening in the winter, you will see the constellation Orion. It's one of the most easily recognizable constellations in the northern hemisphere. The brightest stars in the constellation are blue-white Rigel in Orion's knee and red Betelgeuse in Orion's shoulder. See the image.
Rigel and Betelgeuse are bright because they are huge compared to our Sun. If you could replace the Sun with Betelgeuse, it would swallow Mercury, Venus, Earth, Mars, and most of the asteroid belt. Jupiter would skim the surface of Betelgeuse. See the image.
Betelgeuse is nearing the end of its life and it's acting strange. In recent months, it dimmed to only about half of its brightness. The dimming could be the precursor of its explosion. If Betelgeuse goes supernova, it will be visible in the daytime and could be brighter than the full Moon at night for a few weeks. Betelgeuse is far enough away, 700 lightyears, from the Earth, that we don't need to worry about the blast.
On the other hand, stars like Betelgeuse nearing the end of their lives do vary in brightness without exploding. So, it could be many, many more years until it explodes. The recent dimming does have the attention of astronomers. So, when you go out stargazing in the coming months and years, keep an eye on Betelgeuse.