About 300 million years ago, nearly all land formed a single mass, Pangaea, which began breaking apart around 200 million years ago. It was not the first time: continents gather and scatter in cycles lasting several hundred million years. Models predict that a new supercontinent will form in roughly 200 to 250 million years.
On 27 August 1883, the eruption of the Indonesian volcano Krakatoa was heard as far away as Rodrigues Island, nearly 4,800 km away. Its pressure wave was picked up by barometers worldwide and circled the globe several times. The tsunamis that followed killed more than 36,000 people.
The deepest known point in the ocean, Challenger Deep, lies roughly 10,900 m below the Pacific surface. Drop Everest in and its summit would still sit about 2 km underwater. Down there, the pressure is more than 1,000 times what you feel at sea level, roughly a tonne pressing on every square centimetre.