 How are people on Earth able to help with the search for a missing prospector?
Evans was a prospector, and like all prospectors, a sort of jackknife geologist, selenologist, rather. Once he followed a stampede to Yellow Crater, where he thought for a while that he had a fortune in chromium. They might have appeared to waver slightly, if they were behind outflung corona flares. This was to allow the air-conditioning system to function properly, and to prevent air loss in case of the highly improbable meteor damage. For example, because of an order of his stating that there would be no alcoholic beverages within the survey building, the entire survey was assured of a constant supply of home-made, but passably good liquor. It was used mostly, from sun-up to sun-down, to supplement the nuclear power plant.
 They can see different sides of the moon from the people on the moon
 They can shine a light to make searching easier  Their equipment is advanced enough to connect to the prospector's radio  They can boost the signals of the scanners on the moon  They can see different sides of the moon from the people on the moon