Neptune holds the record for the fiercest winds in the solar system, blowing faster than a fighter jet at up to 1,200 miles per hour. Deep in its icy blue atmosphere sits the Great Dark Spot, a storm roughly the size of Earth.
Unlike every other planet, Neptune wasn't found by pointing a telescope at the sky — it was discovered through mathematical calculations, after astronomers noticed something was tugging on Uranus's orbit. Scientists believe the pressure deep inside Neptune's atmosphere may be so extreme that it literally rains solid diamonds.