Introduction

Is there a way that we can visualise the true scale of the Universe?
In books and on the internet you can find many pictures, diagrams and even photos of groups of celestial objects.
But inevitably, these cannot be true to scale as regards both distances and size of objects.

Photo: Nicole Emanuel When we think about this problem and do some calculations, we do not only become once again impressed by the enormous size of the Universe and even small parts of it like our Solar System, but also realise that space is almost empty, because the objects are so very small in comparison with the distances between them.

In this module we attempt to give a realistic idea about the scale of the Universe and parts thereof, and will show that ultimately, a real sense of scale of the Universe is beyond our comprehension.

Many of the diagrams used in this module are obtained from the great web site Atlas of the Universe. We are very grateful for this excellent material and recommend our readers to visit that web site for much more (click logo).
This material is licensed under these conditions.