With interstellar travel technology you can't detect a ticking bomb in

Ummm... I got the impression that they DID detect it.

What gives you the impression that they didn't?

"...insert corny quote here"

As the script demands, we're not suppose to talk or think about the explosion for the rest of the film. Here, drink this koolaid.





Enjoy these words, for one day they'll be gone... All of them.

They could not intervene before that time as it would risk harming Loise and with their grasp on time they knew that she was vital.

They were able to detect the bomb, as they could see the future. Why one of them decided to die is another question. Probably movie suggests that it's the same reason Louise chose not to change anything even though she knew the future.

They did detect it. Completely. They even tried to warn Louise and Ian about it.

There is another reason to fill your heart with hatred.

They detected it, but the only way to know the intentions of Louise and Ian was to let it play out. Once they were convinced they didn't know, they saved them and didn't attack us.



http://writerblalley.wix.com/home

It's really quite simple. The director needed this to be classified as a sci-fi movie, so added a senseless explosion. Obviously the aliens could have pushed the bomb out before Ian and Louise even got to the ship, not to mention prevented the rogues from ever putting it there in the first place. A shame that an innocent alien had to die because of a director's silly checklist.

they didn't need to detect it as they could see the future. or did you miss that part?

so why did one of them choose to die?

imagine you can see the future. in this future you save your species by dying. this future is the one you want to happen. what would you do?

exactly.