Disclaimer: Doctor who belongs to the BBC, and Russell T Davis probably owns this scene as well. I don't own anything but the idea of snow.
Snow
Humans are very odd, or at least English humans. They complain about the weather all the time, about rain, wind and sun, but when they see snow, they can't help smiling. Snow is cold and can cause dangerous accidents; when it melts, it can feel worse then a cold shower. But when it snows they smile, laugh and play games.
This wasn't real snow, it was ash. And the shooting stars were pieces of the ship burning in the atmosphere. It was not so wonderful then, but it was odd, how the Doctor and Rose smiled and looked at the sky with wonder.
The Doctor had wondered sometimes what it would be like to be human, to be nearly blind and almost deaf. But looking at them now, he saw them seeing something he couldn't see.
Rose was still holding his hand, looking up at the sky and seeing the possibilities, the stars they could travel to. He looked at her and smiled. For a moment he looked like a human, seeing snow.