Rogue Stars and Lava Worlds

A surprising number of geographically diverse cultures associate Sirius with canines (the “Dog Star”), and the origins of this concept are discussed, along with a summary of the descriptions of the Sirius system contained in science fiction. Sirius is the brightest star in the night sky but millions of years ago it was brighter still. We discuss why this is so, and how stars grow, decay and sometimes explode. Stars also move around the known galaxy and sometimes can travel close to our solar system. We explain how both wandering and exploding stars can strongly affect the evolution of life on Earth, with specific reference to stars located in this sector. Also discussed are lava worlds, planets so hot that they have molten surfaces.