Even moons whose surface is mostly frozen ice may earlier have been melted internally by heat from radioactive rocky cores.

He was a product of the rubble rings that fringe the radioactive core of old Bonn.

Undoubtedly it has a radioactive core that has furnished sufficient warmth to support life on its surface.

Can you tell us whether these radioactive cores are in the gorge?

But he had to find the radioactive cores.

They hurriedly transferred the explosives, radioactive cores, and weapons across from the Sea Dragon.

He thought he knew where to place the radioactive cores, but wanted to be sure.

The radioactive cores are up on the deck.

He quickly spotted the sinister metal containers, the radioactive cores.

Twenty people were trapped in the radioactive core- he stood in the shielded observation room and watched them die.