Nasa helps to find temples

Australian researchers have found 74 new temples in a major Cambodian heritage site using Nasa technology.

The academics from Sydney University found the ruins under vegetation in the medieval city of Angkor using hand-drawn maps, ground surveys, aerial photography and ground-sensing radar provided by Nasa. The radar can detect differences in plant growth and moisture that can be cross-referenced with maps and ground surveys to find sites.

The temple city seemed to have been served by a single hydraulic system, but its expansion into surrounding forests may have caused the water system to fill with sediment, leading to the city's downfall, the researchers said.