Milky Way’s Ancient K Stars – “The Best Bet for Planets With Life?”

Oldest Stars of the Milky Way


“The Sun is 10 billion times brighter than an Earth-like planet around it, so that’s a lot of light you have to suppress if you want to see an orbiting planet. A K star might be ‘only’ a billion times brighter than an Earth orbiting around it,” said Giada Arney of NASA’s Goddard Space Flight Center. And, they 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, K stars have less extreme activity in their youth than the universe’s dimmest stars, called M stars or “red dwarfs.”