The Depth of the Night Sky (An Introduction) with Jonathn Park - Intro to Astronomy - November 2025

When we look up at the night sky, it’s easy to imagine that all the stars are placed on a great celestial dome above us. But we know that they lie at vastly different distances, scattered across space, some near and others hundreds of light-years away. In this talk, we'll look at some familiar groups of stars, using graphics to travel away from Earth to view them from different directions. This will help you to get a feel for these distances. While on the topic of how far away these stars are, here's an interesting fact: the speed of light is exactly 299,792,458 metres per second (no additional decimal places, no uncertainty), and this means we can now define a light-year to 100% precision! You'll find out how this works tonight. We will also learn a little about some of these stars - are any binary, triple, or more? How big and hot are they? Do some of them have planets? One is a fascinating system of at least five stars orbiting each other in a very complex pattern. This talk includes a selection of familiar stars visible to the naked eye, and is suitable for all ages and levels of astronomy knowledge. It may even change how you think about the stars you see at night.