Please welcome Professor Wendy Freedom. [Applause] I am standing outside of a cabin, a young girl of seven with my father. We are looking up at a dark sky with more stars than I've ever seen before.And my father is explaining to me that the stars are at unimaginable distances from us and that some of them might not even be there anymore. We're looking at them as they were when their light began its journey to us and some of them may have died in the meantime. The journey might be many thousands and thousand ...

The universe is expanding. And we know that because when astronomers look out at the galaxies around us, they see every galaxy moving away from us at a speed that increases in proportion to the distance. It doesn't mean that there's anything wrong about us, that everybody's moving away from us or that we're at the center of the universe.any other hypothetical observer in any other galaxy would observe exactly the same phenomenon. It's a remarkable fact of our universe. It is expanding.Now that um amazing ph ...