More mystery ahead

HUNDREDS of millions of people across the world held their breath. Each one was anxiously watching a tiny robot on their TV screen. Would the robot actually manage to probe inside one of the world's greatest mysteries - Egypt's largest pyramid?
　The National Geographic Channel's live broadcast of the exploration of the Great Pyramid, outside Cairo, on September 17, 2007 has aroused lots of people's interest in archaeology.
　The robot "Pyramid Rover", measured 12cm wide and 30cm long and had a height that varied from 11cm to 28cm. During the exploration it was linked to a main computer by a fibre-optic cable that carried video signals and controlled all aspects of the robot's movement.
　"Pyramid Rover" crawled about 65 metres up a 20 by 20cm tunnel before drilling a hole in a stone door and then inserting a camera to film what lurked inside.
　Scientists had hoped that the robot would help find clues to the secret of how the pyramid was built. But when it climbed inside, the next mystery was revealed - another locked stone door.
　"Archaeological excavation is just like this - when one mystery is discovered, another comes along," said professor Qi Dongfang from Peking University. "The exploration has taught us that people should learn to use high technology in archaeological excavation."
　It may take the scientists another year of hard work and more new technology before they finally know the answer, said Zahi Hawass, director of Egypt's Supreme Council of Antiquities.
　The pyramids are considered one of the seven ancient wonders of the world. No one really knows how they were built or what they were built for.