A Busy Day on the Moon
You'd think that Apollo 11 would be the only spacecraft chilling on the moon between July 20-21, 1969, but you'd be wrong. The Soviets knew they couldn't beat the Americans in landing humans on the moon, but they at least wanted to be the first to return moon rocks. So they launched the probe Luna 15 to pick up some choice samples, only to have the darn thing crash land on them. Luna 15 struck the moon mere hours before Armstrong and Aldrin lifted off back to Earth, making July 21 the first time the moon was visited by both the Americans and the Soviets on the same day.