How Old Are The Stars In The Night Sky?

The answer is relative to your viewing point. When we look at the Moon, for instance, what we see is an image of how it looked not in real time, but how the Moon appeared 1.3 seconds ago, the time it takes light to travel the 250,000 miles from the Moon.

At just under a quarter of a million miles away, the Moon is right on our doorstep. The stars we see in the night sky are how they appeared thousands or even hundreds of thousands of years ago because of the huge distances light has to travel. Indeed, with telescopes we can see stars that no longer exist because they died before there was life on Earth.

It is these astronomical distances that make finding life elsewhere in the Universe such a long shot. For all we know, there could be an advanced civilisation on a distant planet observing the dinosaurs and concluding there's little point in making contact.