National Geographic : 1962 Aug
KODACHROME C N.G.S. Potent pellets of uranium oxide do the work of coal or oil. Loaded into steel tubes, 813,440 slugs pack enough power to drive the ship 300,000 miles. Until activated, they offer no radiation hazard. Shedding its sheath of protective plastic, a fuel element of steel tubes containing uranium pellets slides into the reactor. Keeping their distance, technicians lower a neutron emitting starter into the core. To lessen exposure, they practiced until they could do the job in ten seconds.