On 1 September 1859, astronomer Richard Carrington saw a brilliant flare erupt on the Sun's surface. Less than a day later, the most intense magnetic storm ever documented hit Earth. Auroras were seen close to the tropics, and telegraph operators got electric shocks; some even managed to send messages with their batteries disconnected.
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.