The US space agency announced on Thursday that an orbiting robot craft has discovered that there may be enough water on the moon to one day support a human colony there and to use the lunar base as a rocket fuelling station for exploration into deep space. "This means that human life could expand to the moon," said a jubilant Alan Binder, lead scientist for the lunar prospector spacecraft.With water available, he said, it will be possible to start building a moon base in eight to 10 years and have a partially self-supporting colony within 15 years.