That’s right. Not only is the light that arrives here from a star 1 million light years away 1 million years old, you should also realise that the star that light originated from is not even in the same place it appears from our perspective. It could be further away, or in a completely different part of the night sky, or both, or may no longer even exist.

Put simply, the sun is eight light minutes away. If it exploded, we wouldn’t know about it for eight minutes.