Mysteries revealed?

Engineers from the Boston firm iRobot and researchers from National Geographic ( news - web sites) and the Egyptian government's Supreme Council of the Antiquities showed the robot to reporters Friday. On Tuesday, it will crawl 200 feet up the 8-inch-square shaft before a live, international television audience.

If all goes according to plan, television viewers and researchers will discover what's behind a door at the end of the shaft at the same moment.

"It's a moment of revelation that scientists get to experience fairly often, but the rest of us don't," said Tim Kelly, president of National Geographic's television and film division.

Then begins the hard work — trying to understand the meaning of whatever is behind the door, said Zahi Hawass, director of the Supreme Council of the Antiquities.

"You have a mystery and the mystery will be solved — what's behind this door, whether it is something or nothing," Hawass said, adding it was difficult to guess what would be found. "Whatever we are going to find, there still will be a lot of work for us to do."

No other Egyptian pyramid has such shafts, Hawass said. The Great Pyramid, built 4,500 years ago by Khufu, a ruler also known as Cheops, has four.

....While researchers remain in one of the chambers in the heart of the pyramid, the robot will be climbing the shaft. The shaft rises over rough stone at a 40-degree angle from the chamber and ends at a door adorned with two brass handles. In a test using ultrasound equipment mounted on the robot, researchers have determined the door is three-inches thick.

Over the next few days, the exploration team will determine how the robot will penetrate the door. Hawass says the robot may drill a hole for a tiny camera and a light to pass through.