8 Oxygen

From Greek osme meaning smell. 

Apollo 13 was the third manned lunar-landing mission. It was flown by James Lovell, Jack Swigert, and Fred Haise. Two days after the launch, The Apollo spacecraft was crippled by an explosison, caused by an electrical fault in an oxygen tank.

1 Hydrogen

Think of her as Hydro Jen, swimming alone, in a one-piece.