Gold in the Sky by Alan E. Nourse, Science Fiction, Adventure (Hardcover)

The rock in space was not quite a sphere, being far too tiny a bit of cosmic debris to have sufficient gravity to round off its ragged corners. One side was rough -- like a ragged mountain top that was broken off at the peak and hurled into space by an all-powerful hand.

Slowly the Scout Ship edged closer, braking with forward jets. Was this it, at last -- the missing asteroid?

Alan Nourse (1928-92) won a widespread and devoted readership for his optimistic novels of space travel, medicine, and alien beings. "Gold in the Sky," featuring young space adventurer Gregory Hunter, made its first appearance in "Amazing Science Fiction Stories" in 1958.