Satellite navigation systems have come to affect countless aspects of our daily lives, from directing our holiday aeroplanes to enabling us to drive round an unfamiliar city without any map other than the one on our mobile phone. Most new cars sold today have an inbuilt Sat Nav and you can buy trackers relatively cheaply… Continue reading Satellite Navigation
Author: Steve Hurley
Hi I am Steve Hurley. Although I work in the IT industry. I studied for a PhD in astronomy in the 1980s. My real passion is explaining scientific concepts to a non-scientific audience. My blog (explainingscience.org) covers various scientific topics, but primarily astronomy. It is written in a style that it is easily understandable to the non scientist.
Publications and videos
For links to my books and videos please visit www.explainingscience.org
The Observable Universe and Its Horizons
Updated 1 February 2026 Although the Universe may be infinite in extent, in the generally accepted Big Bang cosmology we are only able to see a small fraction of it. We call this small fraction we can see the observable universe. Outside the boundary of the observable universe lies the unobservable universe - a region… Continue reading The Observable Universe and Its Horizons
Easter April 4 2021
This year, for the majority of the world’s Christians, 4 April is Easter Sunday, one of the most important dates in the calendar. Although because of the current restrictions due to the Covid pandemic, celebrations will be a little limited in many places. Although Easter is the festival celebrating the resurrection of Jesus Christ from the dead,… Continue reading Easter April 4 2021
Distances in Cosmology
This post has now been superseded by a more detailed post Measuring Distances in Cosmology ---------------------------------------------------------------------------------------------- I recently read an article on the popular astronomy website site Universe Today. It stated that ‘…the CMB [cosmic microwave background radiation] is visible at a distance of 13.8 billion light years in all directions from Earth, leading scientists… Continue reading Distances in Cosmology
Advancing the Clocks
On the early hours of Sunday 14 March 2021, most of the United States will put their clocks forward an hour and Daylight Saving Time (DST) will commence. Two weeks later on 28 March most countries in Europe (including the UK) will follow, switching to summer time. In this post I’ll talk about the practice… Continue reading Advancing the Clocks
Explaining Science 