Mount Everest

Mount Everest is so famous for being so high that you've probably heard of it before. It has been known the world over since the early 1950s when Sir Edmund Hillary and Tenzig Norgay first climbed to its awesome summit. Hillary surveyed Everest at the time and determined that it was 29,000 ft/8840m high - a figure amazingly close to the current reading of 29,035 ft/8850m, which was confirmed using radar and global positioning satellite (GPS) technology.

Using state-of-the-art technology Professor Brad Washburn of the Boston Museum of Science, the world's foremost mountain cartographer, and his team have calculated that earth's highest elevation is actually 7 feet higher than the previous record. That makes the official height 29,035 ft/8850m. Thanks to some engineering whizzes at the Massachusetts Institute of Technology who developed really light, high-tech gear, the work of Washburn was made easier because he was able to hand carry a radar device to the top of Everest where it could be positioned to measure the actual height of the mountain - underneath all that snow. GPS technology was also deployed near the summit, which uses satellite signal relays to take readings from the top of Everest. After months of crunching numbers Washburn's team arrived at the new, official world-record elevation.

They've also determined that the Himalayan Mountains are still growing higher, at a rate of about 2.4 in/6.1cm per year. That's twice as fast as previously thought. A growth rate of 2.4 in/6.1cm per year doesn't sound like very much. But, if you think about it, that means in the last 26,000 years the Himalayans have risen almost a mile into the upper reaches of the earth's atmosphere!