My theory on what happens after they set off the bomb is....Well, nothing. the bomb doesn't cause anything, except maybe a few little things, like the statue losing everything but it's foot. The bomb COULDN'T have set off the bomb in 1977, because their plane STILL crashes in 2004....AFTER 1977, which is when they set off the bomb. 2004 is still the future of 1977!!!!!!!! the bomb, like Miles said, could even CAUSE the plane to crash. The bomb wont do ANYTHING!!!!