1) The phenomenon known as "black holes" occurs when matter is crushed into an infinitely small space, creating a gravitational pull so strong that nothing can escape.

2) The Andes, stretching along the western coast of South America, is the longest mountain range in the world, spanning over 4,300 miles (7,000 kilometers).

3) In Norse mythology, Ragnarok is a cataclysmic event that signifies the end of the world. It involves a series of apocalyptic battles and natural disasters, leading to the destruction of the gods and the world as it is known. From the ashes, a new world and a new generation of gods emerge.

4) Aztec mythology, originating from ancient Mesoamerica, includes deities like Quetzalcoatl, Huitzilopochtli, and Tlaloc. It explores concepts of creation, sacrifice, and the cyclical nature of time, with intricate cosmology and rituals forming a significant part of Aztec religious beliefs and practices.