Moving the Earth's Prime Meridian

Tourists who want to take photographs at the prime meridian often stand at the Royal Observatory in Greenwich, England. "Most people stand on the stripe and have their picture taken, with the sundial in the background," said Ken Seidelmann, an astronomer at the University of Virginia. Seidelmann learned that many people reported that their GPS devices listed the line of zero degrees longitude in a completely different location than at the landmark.