Using scanned maps and data from the United States Geological Survey (USGS), Esri developed an interactive tool to explore ...

This story appears in the May 2005 issue of National Geographic magazine ... Einstein’s realm, where time is relative, mass and energy are interchangeable, and space can stretch and warp.

Nasa studies a pair of twins To date, the fastest speed a crewed mission has achieved in space is 11.08km/s, which is only 0.0037 per cent of the speed of light. The time dilation effect at this ...