Also known as mock suns or phantom suns, sundogs are an atmospheric phenomenon that consists of a pair of bright spots on either side of the Sun, often co-occurring with a luminous ring. These are created by the refraction of light from plate-shaped ice crystals either in high and cold cirrus clouds or, during very cold weather.
Great Blue Hole
Most people have seen pictures of the Great Blue Hole in Belize, however few know how it actually came to be. The Great Blue Hole was originally an inland cave at a time where sea levels were much lower. But as sea levels began to rise, the cave was flooded. Today, the hole is over 300 meters (almost 1000 feet) across and is 124 meters (400 feet) deep.
Christmas Island red crab migration
Measuring up to 12 centimeters (5 inches) wide, the Christmas Island red crab is a species of land crab endemic to Christmas Island and the Cocos Islands in the Indian Ocean. Usually, the crabs hide in burrows in local forests, however, each year they migrate to the coast to breed. For over a week, local roads turn red as millions of crabs move to the coast.
Read more: https://list25.com/25-bizarre-natural-phenomenon-that-actually-occur-on-earth/2/