"Looks like it," replied Tom. "But on the other hand," he continued,
"why wasn't there some report of it when the first expedition came out
to look over the satellite?"

"I can't answer that question, Tom," answered Roger. "But I'd be willing
to bet my last credit that there's uranium on this space-forsaken rock.
And a whopping big deposit of it!"

They reached the air lock of the _Polaris_ and climbed wearily aboard.
At the end of the first day, on the new satellite, they were exhausted.
A few minutes after entering the giant cruiser they were all sound
asleep.

Dawn of the second day on Roald saw the vast plain crowded with men at
work. The first community objective was the construction of an
atmosphere station, and before the woman and children had finished
lunch, they were breathing synthetically produced air.

Working from a master plan that had been devised back at Space Academy
before the expedition blasted off, the colonists were divided into three
separate crews: the wreckers, those who would remove essential parts
from the spaceships as they were needed; the movers, those who would
haul the parts to construction sites; and the builders, those who would
take the parts and construct the community buildings.

The first and most difficult job was building a gigantic maneuverable
derrick and jet barge for removing, hauling, and installing the heavy
machinery.

Astro had been assigned to the crew responsible for the construction of