His most recent was in 2011.22 Babu Chiri Sherpa has remained at the summit for the longest single period: 21.5 hours in 1999.23 Since the first recorded deaths on Everest in 1922, approximately 235 people are believed to have died on the mountain.24 Avalanches are the foremost cause of death, followed by falls.25 The first blind person to reach the summit was the American Erik Weihenmayer in 2001.26 A 1976 US study concluded that Sherpas had undergone genetic adaptations after living in one of the world's highest regions for thousands of years.27 Climbers start using bottled oxygen at 26,000ft.
It makes a 3,000ft difference in how they feel.28 The mountain is more than 28 times the height of the Shard.29 In 1924, the Britons George Mallory, 37, and Andrew Irvine, 22, disappeared on Everest. In 1999, Mallory's body was found at 27,000ft.30 On , Pem Dorjee Sherpa and Moni Mulepati became the first couple to be married at the summit.31 The summit is just below the cruising height of a jet (around 31,000ft).32 An estimated 900lb (400kg) of human waste was removed from the mountain during clear-ups between 20.33 More than 33,000 feet of fixed rope is used every year to set the South Col route.34 In 1934, the soldier and eccentric Maurice Wilson attempted to climb Everest solo despite little or no mountaineering experience.
His body was found in 1935 near the 23,000ft mark.35 The Italian climber Reinhold Messner made the first successful solo climb in 1980.36 Messner's other record is to be the first to reach the summit without oxygen, achieved with the Austrian Peter Habeler in 1978.37 Temperatures on the mountain can get as low as minus 60C.38 Temperatures can surpass 38C in the Western Cwm, which climbers go through to reach the summit.39 The Australian climber Christian Stangl holds the record for the fastest ascent, made on .
He reached the summit from Camp III – without oxygen – in 16 hours and 42 minutes.
1 The officially recognised height of Mount Everest is 29,029ft (8,848m), based on a 1954 ground-based measurement.
These were originally basalt lava flows several meters to tens of meters thick.
The same year, Nepal opened up access to Everest's south side.51 Davo Karnicar from Slovenia was the first person to ski down Everest, in July 2000.52 Sherpas suffer altitude sickness like everyone else.53 In 1953, Sir Edmund Hillary and Tenzing Norgay reported seeing large footprints while ascending.
Hillary later discounted Yeti reports as unreliable.54 Last week, the Japanese geriatric Yuichiro Miura, aged 80, became the oldest person to climb Everest.
The model K-Ar ages for each of the samples ranged from 405.1±10 Ma to 2574.2±73 Ma.
Furthermore, the seven samples from the small amphibolite unit near Clear Creek, which should all be the same age because they belong to the same metamorphosed basalt lava flow, yielded K-Ar model ages ranging from 1060.4±28 Ma to 2574.2±73 Ma.