The Power of the Atom

 is a Fallout 3 quest. It is also a PS3 trophy, and an Xbox 360 and PC achievement.

Objectives and Walkthrough
This quest is given to you by:
 * The Sheriff Lucas Simms, who wants you to disarm the nuclear bomb in the middle of Megaton
 * Mister Burke who wants you to help him detonate it, 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 casually 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; Mentats can be used to boost your statistic.

In the Japanese version of Fallout 3, Mr. Burke does not appear and the player cannot get the Fusion Pulse Charge. The only options are to disarm the nuke or ignore 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.

Mr. Burke will give player the privilege to push the button to detonate the bomb. Doing so instantly gives the player a Karma of -1000. If your karma before was 0 or negative, -1000 karma will instantly lead to the lowest possible karma in the game.

If you help Roy Phillips take over Tenpenny Tower in the quest Tenpenny Tower prior to completing Power of the Atom, you may still complete Power of the Atom. When you return to the top floor penthouse, you will stumble onto Roy Phillips and Mr. Burke having a conversation. Roy is intimidated by Mr. Burke and the fact that he made his way to the top floor. Roy agrees with Burke on the matter of blowing up Megaton and also states that he could use a man like Burke, thus Burke begins a new partnership with Roy Phillips.

Disarm Megaton's atomic bomb
Lucas Simms wants you to disarm Megaton's bomb. Your Explosives skill must be at least 25 to attempt this. Eat some mentats. If you are successful you get a cash reward and the keys to your own Megaton House. The cash reward is usually 100 caps, but with a successful use of your speech skill on Lucas (before you actually disarm the bomb) you can talk him into 500 caps instead.

Mr. Burke would leave Megaton after you defuse the bomb. As a result of disarming the bomb, Talon Company mercenaries hired by Mr. Burke will randomly appear in an attempt to kill you.

Optional: Deal with Mr. Burke
This section of the quest is entirely optional. You can kill Burke after speaking to him, without talking to Simms first, killing him will result in good karma and you can avoid risking Simms. You can also accept the monetary reward to blow up Megaton, and then kill Mr. Burke, without penalty.

Report Mr. Burke to Lucas Simms
After speaking to Burke, a new dialogue option will become available when speaking with Lucas Simms, which can result in him confronting Burke about the plot to destroy Megaton, as long as your Karma is low enough. Take care not to "cry wolf," so to speak, because he will not believe you if you rescind your initial warning. Lucas Simms will tell you to follow after informing you that you're about to see Wasteland justice first hand. Simms will attempt to arrest him. Burke will deny the allegations, but will eventually agree to be detained and suggest that Lucas "Lead the way." As Simms turns to lead Burke to jail, Burke pulls a silenced 10mm Pistol on him and kills him. (It seems that, if Simms manages to exit the room before Burke takes the shot, the latter will just shoot at nothing in particular. Lucas Simms can then be found dead, outside the saloon.) However, if you are quick enough, you can kill Burke as soon as he pulls out his gun. To do this, have a high powered gun (Scoped .44 Magnum, Sniper Rifle, Combat Shotgun or possibly even a Police Baton) drawn and ready while the two are having their conversation, and as soon as Mr. Burke draws his gun, blast him (preferably a headshot to ensure a kill) manually or with V.A.T.S.. If it takes more then 1 shot to kill him, Mr. Burke may still kill Simms. You can try to shoot the silenced 10mm out of Burke's hand instead of killing him. This will give the sheriff time to respond and give you more wiggle room in dealing with Burke. If you kill Burke before he kills Lucas, the sheriff will thank you afterward.

If you don't act fast, Simms is killed. Afterward, Mr. Burke gives you a threat and disappears. If you kill Burke before he disappears, he says his friends will avenge him. If you let Burke kill Lucas Simms, then you kill Burke, you can loot both bodies. This will get you a Silenced 10mm Pistol and a Chinese Assault Rifle, plus some caps, ammo, and other assorted items. If Lucas Simms dies you can still complete this quest by talking with his son, Harden Simms, after disarming the bomb.

Neither option will result in a negative reactions from the townspeople, though they may comment "better him than me" if they see it take place. If in any way the vault dweller accidentally hits Simms, the town may become hostile and retaliate.

Seducing Mr. Burke
If you play as a female character and have the Black Widow perk you can seduce Burke into getting another person to do the job and taking you out of the city; he will even send you love letters. Another possibility is persuading him to give you 500 more caps upon detonation of the bomb.

Using the Black Widow Perk to seduce Burke still results in him putting a hit out on you.

If you disarmed the bomb

 * Bottle Caps
 * 500 - If Speech was successful at start of quest
 * 100 - If Speech failed, or wasn't employed at start of quest
 * My Megaton House Key
 * Deed: My Megaton House
 * 300 XP
 * Karma [+200]: If you disarmed the bomb for free
 * A Contract for Extermination will be set out on you by Mr. Burke or Allistair Tenpenny; Talon Company will start hunting you.

If you destroyed Megaton

 * Bottle Caps
 * 1000 - If Speech was successful at start of quest
 * 1000 - If the Black Widow perk was taken and unique dialog is chosen
 * 500 - If Speech failed, or wasn't employed at start of quest
 * My Tenpenny Tower Suite Key
 * Deed: Tenpenny Tower Suite
 * 300 XP
 * Karma [-1,000]: If Megaton is destroyed
 * With a lot of negative karma, the Regulators will start hunting you. You might also be ambushed by angry former Megaton citizens.

Bugs

 * After disarming the bomb, Lucas Simms will not give you 500 caps if you had a before successful speech attempt sometimes.
 * After disarming the bomb and Burke killing Lucas Simms, there is the possibility of Harden Simms being teleported to an unreachable place outside Megaton, the only way to get your reward is to move (to) Harden using a console command
 * After disarming the bomb, Mr. Burke disappears and then re-appears after unleashing Feral Ghouls in during the Tenpenny Tower mission.
 * If you speed through Vault 101 and try to escape as quickly as possible, you have a shot at an odd bug. Simply put, if you get to Megaton fast enough, Burke will not be in Moriarty's. Instead, he'll be outside, walking up to it. After engaging him in conversation quickly and taking the fusion pulse generator, head quickly to Simms and tell him about Burke's plan. Afterwards, Simms will run to Moriarty', then head back to Burke. He'll talk to him for three seconds or so, then drop dead instantly.
 * The game crashes after blowing up Megaton, if you try to go through the doors. - the karma level can't be dealt at a higher level than 20 - lowering to 20 is a solution: "player.setlevel 20"&#160; (Setting your level back to 30 after entering the doors will instantly crash the game unless there is a fix that has not been added)
 * After Megaton is destroyed and the player finds Moira roaming outside Megaton, she will sometimes talk as if she is in her store, except she won't sell items and she still offers repairs. She won't seem to comment on the explosion of Megaton.
 * To maintain Neutral Karma you have to succeed in the speech challenge with Lucas Simms after disarming the bomb to receive more caps.
 * If you originally rigged the bomb to explode, but did not detonate it and instead killed Burke/Tenpenny, the game will render the bomb as "rigged" and not allow you to disarm it.

YouTube Video
The destruction of Megaton AmXHN5XEKOk