Betelgeuse supernova. Artwork of the explosion of the star Betelgeuse as a supernova. The Earth (centre right) and Moon (lower left) are also seen. Betelgeuse (Alpha Orionis) is a red supergiant star in the constellation Orion. Astronomers believe that it is close to the end of its life and it could explode as a supernova at practically any time soon. A supernova is the cataclysmic death of a huge star, which can shine more brightly than an entire galaxy for a while. The three stars forming Orion's Belt can be seen below Betelgeuse at centre.