In honor of America's 250th birthday, here are 50 must-see American movies that celebrate who we are, who we've been and who ...

Evolution is always happening — so why can't we see it? A biologist explains the timescale problem, election pressure, and ...

Scientists say moons around rogue planets wandering through the galaxy could remain warm enough for life thanks to tidal heating and hydrogen-rich atmospheres. These dark, starless worlds may have had ...

Universally defined by their cultural impact and literary imagination, these science fiction books are must-read classics ...