The Power of the Atom

 is a Fallout 3 quest. It is also an Xbox 360 achievement.

It is given to you by Mister Burke, who wants you to help him detonate the nuclear bomb in the middle of Megaton, as his employer, Allistair Tenpenny, considers it a blight on the landscape of the Capital Wasteland. Burke can be found in Moriarty's Saloon in Megaton causually sitting in the corner.

Rig Megaton's atomic bomb to explode
To do it, you have to put a Fusion Pulse Charge given to you by Burke inside the bomb. Your Explosives skill must be 25 or higher for you to attempt it.

Report to Mister Burke in Tenpenny Tower
After rigging the bomb, meet Burke at Tenpenny Tower, which is southwest of Megaton. There you can observe the explosion from a safe distance together with Burke and Tenpenny.