Mount Everest
The summit stands near the height where airliners cruise, in air that holds only about a third of the oxygen at sea level.
The height of 8,848.86 metres was announced jointly by China and Nepal in 2020, after surveyors carried satellite receivers and ground-penetrating radar to the summit to measure the rock beneath the snow. Earlier figures differed by a few metres, and the mountain is still rising by a few millimetres a year as the Indian plate pushes north into Asia.
The summit is made of marine limestone containing fossils of sea creatures from the Ordovician period, around 450 million years old. Rock that once lay on a seafloor now sits higher than anywhere else on Earth's surface.
Everest is the highest point above sea level, but not the tallest mountain from base to peak: Mauna Kea in Hawaii rises about 10,000 metres from the Pacific floor. Nor is its summit the farthest point from Earth's centre; that honour goes to Chimborazo in Ecuador, lifted by the bulge of the planet at the equator.
For all that, it is a wrinkle. Everest's height is about 0.07% of Earth's diameter. On a globe 30 centimetres across it would rise just 0.2 millimetres, about three human hairs thick. The Moon, the next stop, is nearly 400 Everests wide.
- Size
- 8.85 × 10³ m
- Height
- 8,848.86 m
- First ascent
- 29 May 1953
- Summit air pressure
- about 1/3 of sea level