Such brilliance comes at a price, however. Betelgeuse is one of the most famous stars in the sky because it’s due to explode someday. Betelgeuse’s enormous energy requires that the fuel be expended quickly (relatively speaking), and in fact Betelgeuse is now near the end of its lifetime.
Someday soon (astronomically speaking), it will run out of fuel, collapse under its own weight, and then rebound in a spectacular supernova explosion.
When this happens – which could be tomorrow or a million years in the future – Betelgeuse will brighten enormously for a few weeks or months, perhaps as bright as the full moon and visible in broad daylight.
Fortunately for us, it appears that there will be few, if any, adverse affects to Earth when Betelgeuse goes supernova.
If Betelgeuse were side by side with our sun, you’d find it 10,000 times brighter than the sun in visible light. It might be surprising then to learn that the surface temperature of Betelgeuse is only about 6,000 degrees F (3,600K) in contrast to the sun’s 10,000 degrees F.
NOW, THE QUESTION IS...
Will Betelgeuse become a second sun?
Short answer: no. If you’ve read or heard that the star Belelgeuse might explode in a few weeks or a few months – that it will temporarily add a second sun to Earth’s sky and somehow also possibly prove the world will end in 2012 (to which we can only say, “huh?”) – you might want to find more reliable sources. While it’s possible that Betelgeuse will explode in our lifetimes, it isn’t likely. Someday, Betelgeuse will become a supernova. This event is just as likely to happen thousands or millions of years from now as tomorrow.