Black Hole
It was the first nightmare that I've had in a while, at least the kind that I woke up kinda scared. I was watching a game, a football game I think, and for whatever reason the camera changed to show the space shuttle doing some repairs to a satellite. The lady in the space suite suddenly went back into the air lock, fast enough that she kicked off a door or hatch or something on her way in. She was scared. There was a black hole that appeared very close by, and it was one of those things that even though it doesn't affect you right away, you know that this is going to end things as you know it forever (or in this case, eventually suck the earth up). Woke up scared after this one.