Can somebody please explain to me what spatial perspective is?

Battleship (2012) movie. Somebody please explain this scene...?

• I've watched the 2012 movie, Battleship. And I 've have to say it is a freaking awesome movie!! But there were a scene where i don't really get it, could somebody please explain this scene to me... **Warning. Might have a little spoiler!** The scene was when the timid scientist was "forced" to sneak back to his base (where the aliens are trying to using it as their communication base) to retrieve his communication equipment. Then right after he found his equipment, he turned back and was faced with one of the aliens! The question is: How & Why didn't the alien killed him? and he even managed to escape? Anyone who understand and remembered which scene I am talking about, please kindly explain! Thank you! :) for those who haven watched it yet, go watch! It's a awesome movie!!

• Answer:

  I'm not to sure so I may be wrong. But there was also that scene with the boy playing baseball and that giant alien cannonball like thing going around smashing everything. When the ball was in front of the boy it scanned him and when it cleared the boy it's screen went green. The boy was not a threat and had no intentions to harm or attack the ball. The same thing happens with the timid scientist. There is no way he was going to attack the alien. The alien scanned him and his screen went green so he was not a harm. If you watch the ships at the start then you see it is the humans that fire the first shot. As off the equipment, I'm guessing the alien didn't realize what it was. Anyway I may be wrong but that's what I'm guessing.