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For three years, Roxanne Vogel trained, single-mindedly, with one number in mind: 29,029 feet.
She slept in a special tent, outside her home in California, that simulated high altitude. She summited dozens of peaks, on nearly every continent. And finally, last year, Vogel climbed up to 29,029 feet in the Himalayan mountains – the top of Mount Everest, the world’s highest peak.
“That’s the closest to heaven, or the closest to outer space, that I will ever get on this Earth,” Vogel, 35, told NPR. “It’s kind of life-changing, when you’re up there.”
Courtesy of Roxanne Vogel
(And Roxanne didn’t just climb Everest; she set a speed record doing it. In May 2019, she traveled round-trip from her California home, to Everest’s peak and back, in just 14 days.)
But that number — 29,029 feet, from sea level to summit – to which Vogel dedicated so many years of training, may not be the actual height of Everest – or at least not for long. Because the mountain is changing.
Scientists say Everest is getting taller, over time, because of plate tectonics. As the Indian plate slips under the Eurasian plate, it uplifts the Himalayas. But earthquakes can reduce their height in an instant. After a 7.8-magnitude quake in 2015 killed thousands, including climbers on Everest, scientists suspect the mountain got shorter.
So China and Nepal, on whose borders Everest stands, decided it’s time to re-measure Everest.
This spring, with the climbing season canceled for COVID-19, China sent a survey team up to Everest’s summit, carrying GPS receivers. Last year, Nepal did the same. The two countries have been analyzing their findings for months, and are expected to release them any day now – possibly as early as this weekend. Calculating that number has evolved as our technology has, but the science remains complicated.
SIR GEORGE EVEREST, AND AN INDIAN MATHEMATICIAN
Back in the 19th century, when Sir George Everest – a Briton – was the Surveyor General of India, under colonial rule, they used trigonometry to measure mountains, with machines called theodolites. They’re optical instruments – sort of a cross between a telescope and a compass – that are used to measure angles between visible points on the horizon, and vertical planes. Municipal surveyors still use tripod versions of them.