K-type dwarf stars are dimmer than the Sun but brighter than the faintest stars. These stars live a very long time — 17 billion to 70 billion years, compared to 10 billion years for the Sun — giving plenty of time for life to evolve. Also, they have less extreme activity in their youth than M-type stars (red dwarfs), the most common star type in our Milky Way Galaxy. An artist’s concept of a planet orbiting in the habitable zone of a...
