Did Kelvin die before the ending? (Not really a spoiler)
There is a scene near the end when Kelvin is having a troubled sleep, alone on the bed. His visitor left to get herself blasted by that ray gun.
There is one scene where it shows a large hole ripped in the wall of his room, twisted metal, blood, and beyond it, outer-space. Is it possible that he died from some accident and now HE is a visitor to someone else? If not, why show that image? Just a bad dream?