What was heading toward Fifield and Milburn?

I tried to search for a thread that talked about what I am going to say but could not find anything. So here I go. If I remember correctly while Fifield and Milburn are stuck in the temple during the sandstorm at one point Janek notices that one of the scanners has picked up something. He then radios to the two in the temple and tells them that it is moving towards them, I believe heading West. To which either Milburn or Fifield say then I am heading East (or the opposite direction). After this event is when they stumble upon the hammerpede and we all know what happens next. My question is what was the moving object that was headed towards the two trapped scientist? It seems that the story never went back to this happening and never gave it a second look, just left it hanging. Also, I think that the holes in the sleeping pods and the slime that David found on the controls are really important parts to the story. Why, after 2,000 years was the slime on the controls still pliable, sticky. I would think that it would have dried out after such a long time. I also find it strange that the holes in the sleeping pods is never mentioned by anyone in the film. They had to have noticed them. Sorry I am rambling but here is my final idea. I believe something got out in that temple 2,000 years ago and killed the engineers in the temple. I also think that maybe one of those things may be on the ship that Shaw and David leave on at the end of the film, waiting for the right time to reveal itself. Thanks, and I await you comments.