Packs of dog-shaped robots could one day roam the moon — if they can find their footing on Earth first

A prototype of the four-legged robot Spirit training in the mountains.

"A dog is a man's best friend," the old saying goes. Can the same soon be said of robot dogs?

This summer, a group of scientists will travel to Oregon's snow-capped Mt. Hood to train a dog-shaped robot named Spirit how to walk. The slopes of Mt. Hood are strewn with volcanic rocks and sprinkled with glaciers, a rugged environment that researchers think resembles the moon — which Spirit is being prepared to eventually explore.