Is Mt Everest the tallest peak?

SCIENTISTS are using the latest equipment and most modern techniques to measure to an accuracy of 10 cm the height of Mt Everest and test the validity of an American astronomer's announcement in 1987 that Mt K2 (Godwin Austen) is the world's highest peak.

Giorgio Poretti, who is implementing a project to study the evolution of the highest Himalayan peaks, says both mountains are growing but he is not certain which is growing at a faster pace. "To know this, we have to conduct a similar study in Pakistan. At present, we believe that both the Himalayan peaks are gaining one centimetre each year," he says.

Poretti, who is head of the physics department at the University of Trieste in Italy, says his team is using laser-operated trigonometric levelling and distance-measuring instruments and data collected with the help of the global positioning system (GPS) network. Everest's height was last measured in 1974 by China's National Bureau of Surveying and Mapping, but with an accuracy of 70 cm only.
Many problems The present study needed installation of a 15-kg tripod with a double set of three prisms on Everest's summit by professional mountaineers from Nepal and Europe, who encountered several problems. "The first day, four of our mountaineers carrying GPS instruments and the tripod stand ran out of oxygen about 200 metres short of the summit. The instruments were left there and could be taken to the summit only 24 hours later," says Poretti.

The next day -- September 29, 1992 -- proved to be a happy day for the researchers because nine climbers were able to install the equipment on the summit of the mountain, though four of them took a great risk by undertaking the climb even though they were without their radio-sets.

"That day when we saw the red ruby beam of the laser reflected back, our hearts filled with joy," says Poretti. "We knew our mission was close to success and this feeling became a certainty when we heard on the radio that it (the laser beam) could be seen also on the Tibetan side."

The project, being implemented jointly by Nepal and Italy, requires the setting up of three observation stations in Nepal and three more in Tibet. "The accuracy of the measurements so far has been surprisingly high probably due to the low density of air," Poretti disclosed. He expects to announce Everest's exact elevation soon and then turn his eyes to Mt K2, which inspired the project.