It seems obvious at first, the night sky is dark because there is an absence of light. There is an absence of light because the Sun has moved behind the Earth from our perspective as part of the daily rotation of the Earth about its axis. Simple. So why am I asking this question? Well, as you may have guessed, the answer is not as simple as it may at first seem.

We have different understandings or thoughts on the universe, we call these models. Albert Einstein was among those who believed in a static model, one that states that we occupy a static universe, that is to say that it is neither expanding nor contracting, rather that it is infinite and eternal.

If we are to assume this to be true, and also assume that stars are evenly distributed around the universe, then we are still left with our question: “Why is the night sky dark?”. This is known as ‘Olbers’ Paradox’. Why are we left with this question? Read on! Read more »