I kindly asked the soldier to stand at the very edge of the map so we could track his rocket blast. I wanted to see if it would make it to the other side of the map. He obliged, and let one rip, and since I was on free cam, I was able to stay in the air as the rocket sped past me. I followed it as best I could, expecting to see the charred mark where it landed. Except it didn't land -- it kept on going into the distance. Bye bye, rocket. I wondered which map it landed on, since it wasn't ours.
There are lots of maps parked next to each other in TF2. For instance, the Egypt map has the Sudan map next to it but no one ever plays on it. Not enough gimmicks.
This map happened to be Badlands, so I knew Dustbowl was around the corner. I changed maps and there was no sign of the rocket on Dustbowl, either. Gravel Pit was on the other side, so I quickly hopped over there and there was still nothing.
We had a report of the rocket being on 2Fort but it was the wrong color, so I didn't have to investigate. Another reported it on Turbine, but that's an indoor map, silly.
I can assume it's still out there, circling the earth, or whatever planet TF2 is part of.