Squeezed between the Pacific Ocean and the Andes, the Atacama is the driest non-polar desert on Earth: some areas average less than a millimetre of rain a year. Its soils are so arid and so poor in microbial life that they resemble those of Mars. NASA and other agencies therefore test instruments there that are designed to search for life on the red planet.
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.