Usuallly the moon is grey, and Mars is red, right? Tycho is on the moon, so this should be grey.

This is not the most clearly-written precis:

Prospecting on the moon was grim, dangerous and usually unrewarding. Only most of the greenhorn to came to try and find out until after they got there.

Chris Jackson was no exception. He put everything he owned it could borrow into this and be ruined if he failed.

His only chance that going into Tycho – where three expeditions had already disappeared. He could try . . . but would he come out again. . .?

That's a good question and I'm sure it's adequately answered by the 115 pages that follow. I trust Simak. Unrelated, but pertinent: my last office space at the newspaper was about six feet from where Simak's desk was once located, long ago.