Odd truths about Earth

How much does a cloud weigh?

An average cumulus cloud holds roughly 500,000 kilograms of water — about 1.1 million pounds, or 550 tons. It floats because the air underneath it is denser than the cloud is, not because the cloud is light.

Does it ever snow in the Sahara desert?

Yes. The town of Ain Sefra in Algeria, known as the gateway to the desert, has had snow settle on its red dunes repeatedly — most famously in December 2016, the first snowfall there since 1979, and several times since.

Is there an ATM in Antarctica?

Yes — one. There is a working ATM at McMurdo Station, at 77 degrees south, operated by Wells Fargo. It is the only cash machine on the continent, it dispenses US dollars, and a technician flies down to service it roughly every two years.

Is Mount Everest the tallest mountain on Earth?

Only if you measure from sea level. Measured from base to summit, Mauna Kea in Hawaii is taller: about 10,210 metres from the sea floor to its peak, against Everest's 8,849 metres above the sea. And measured from the centre of the Earth, Ecuador's Chimborazo is the farthest point out, because the planet bulges at the equator.

How many times does lightning strike Earth every second?

About 44 times a second, give or take five. NASA satellites counted roughly 1.4 billion lightning flashes a year across the whole planet. By the time you finish reading this sentence, lightning has flashed around 200 times.

Is Antarctica a desert?

Yes. A desert is defined by how little precipitation falls, not by heat or sand, and the usual threshold is under 250 millimetres a year. Antarctica's high interior gets less than 50 millimetres, drier than much of the Sahara, which makes it the largest desert on the planet.

Does dust from the Sahara feed the Amazon rainforest?

Yes. A NASA satellite measured about 27.7 million tons of Saharan dust blowing across the Atlantic to the Amazon basin each year, carrying roughly 22,000 tons of phosphorus. That is about the amount of phosphorus the rainforest loses every year to rain and floods, so the desert is topping up the jungle.

Is Australia moving?

Yes, about 7 centimetres a year to the north-east, faster than any other continent. The drift is quick enough that in 2017 Geoscience Australia officially shifted the country's map coordinates 1.8 metres to catch up, so that GPS would keep pointing at the right spot.

Is the water on Earth older than the Sun?

A good share of it, yes. A 2014 study in the journal Science estimated that between 30 and 50 percent of the water in Earth's oceans formed as ice in the cold cloud between stars, before the Sun existed, and survived the Sun's birth to end up here.