The Earth may soon have a second ‘sun’ as the red supergiant star, Betelgeuse, is expected to go supernova. The dying star is some 640 light-years away in the constellation of Orion. But don’t panic yet. Our planet has little worry about right away, even if Betelgeuse becomes a black hole. Even it if explodes today, we won’t know about it for 640 years. On the other hand, it may have exploded 638 years ago, which means that we’ll see this spectacular event next year in 2012.
Being so far away, there is little damage Betelgeuse could do. For several weeks following it going supernova, Betelgeuse would become the brightest object in the sky after our Sun and Moon. Such a supernova could even turn night into day, but, again, it would be a temporary situation.
As far as any additional radiation, there would be little effect on the Earth. Neutrinos would be the first sub-atomic particle to bombard us from such a supernova. However, these charged particles have very little mass. Even today, our own Sun, as well as other cosmic sources, bombard the Earth with neutrinos. They pass harmlessly through everything, including our bodies.
So what is all the excitement about? How would Betelgeuse going supernova spell doom for the Earth? Several supernovas in the distant past caused a great deal of concern and unrest. Ancient peoples, not understanding what was happening, saw such a dramatic change to their night sky as a bad omen. Some of the earliest recordings in history now believed to had been supernovas, such as one in 185 B.C. was noted by many cultures, from China to Rome. Another in 1006 A.D. was also seen and recorded by peoples around the Earth. Hopi Indian mythology tells of how just prior to the end of our world, a bright blue star will appear. Could Betelgeuse be it?
According to astronomers, about 16 stars in the Milky Way are prime candidates for becoming supernovas. Betelgeuse is the closest to Earth. When the red supergiant explodes, it will rival our own Sun for several weeks, eliminating night. But as the supernova fades, it will remain as a faint object, forming into a beautiful nebula. These colorful regions of gas are quite striking, but pose no long-term threat to our planet. Concerns that Betelgeuse may become a black hole are not unfounded, but even then, it will have little immediate affect on the Earth.