Human Spaceflight, Robotic Spaceflight, Solar System Rusty Schweickart: From the Apollo program to the asteroid threat
The Sun The Sun has an 11-year sunspot cycle. Do we know if other stars have similar lengths, or is our star unique?
Stars Proxima Centauri is a red dwarf star, so would it appear red from the surface of an Earth-like planet in that star’s habitable zone?
