Measuring Distances in Cosmology

I have recently written an article for my local amateur astronomical society about distance measurements in cosmology. There is a lot of confusion about what we mean by "distance" on the vast such scales and the article was written to help clear up of these misunderstandings. It is an expanded version of a shorter blog… Continue reading Measuring Distances in Cosmology

James Webb Telescope

On 18 December a Ariane 5 rocket will take off from the  Guiana Space Centre in French Guiana, aboard it will be the $12 billion James Webb Space Telescope (JWST) - the most expensive scientific instrument ever launched into space. In this post I’ll talk about this remarkable telescope and the mission to deploy it.… Continue reading James Webb Telescope

September 22 the equinox

In 2021 September 22 is the date of the September equinox and is also the first day of autumn (or the first day of spring if you're one of my readers in the Southern Hemisphere). In this post I’ll talk about the equinoxes and discus the commonly held view that they are the two days in… Continue reading September 22 the equinox

June 21 2021 – the solstice

This year, the June solstice will fall on 21 June.  In the northern hemisphere, it is the day when there is the most daylight and when the Sun is at its highest in the midday sky. The origin of the word solstice is from two Latin words:  sol, which means Sun, and sistere, to stand still. On the… Continue reading June 21 2021 – the solstice

Dark energy an unexpected finding

I offered recently to write an article for my local astronomy society on the discovery of dark energy.  It is  an expanded version of the blog post I wrote  on the topic last year and, at over 3000 words, it is longer  than my usual posts. I thought it would be of interest to many… Continue reading Dark energy an unexpected finding