On this Valentine's Day, watch a video about certain chemicals - including dopamine, oxytocin and vasopressin - making you feel good around someone you love.
Chuck Yeager, a military test pilot, became the first to break the sound barrier on October 14, 1947. Afterwards, he was dubbed "the fastest man alive."
A new study suggests that Saturn's moon Mimas may have a subsurface ocean. If so, the "Death Star" moon would join other ocean moons in the outer solar system.