Greg responds...

Captain Atom is 70 years old (though he doesn't look a day over 28).

Cap is connected to the quantum field via his silver skin, which allows him to access clean (NOT RADIOACTIVE) energy and fire off bolts of energy. That same energy can also be used to power his flight and even to enhance his strength. His skin also makes him largely invulnerable. And he can even survive in deep space without a pressure suit of any kind, as long as he has oxygen. (He still needs to breathe.)

Cap can also ABSORB energy and redirect it back to the quantum field. But there's a limit as to how much energy he can absorb and how quickly. If he takes in too much energy at once, the excess will be used as fuel for a one-way trip into the future. The more he absorbs the further into the future he'll jump.