For centuries, witnesses have described glowing spheres floating for a few seconds during thunderstorms. Long dismissed as legend, ball lightning was filmed by chance in 2012 by a research team that captured its spectrum. It contained silicon, iron and calcium, elements found in soil, supporting the idea of earth vaporised by a lightning strike. No theory has yet won consensus.
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.