Effects of Large Satellite Constellations on Astronomy

  Many of you will have seen the images back in 2019 which showed  long ‘trains’ composed of up to sixty SpaceX Starlink satellites crossing the sky in a straight line. These pictures hit the headlines not only because of the number of satellites, but because of their brightness. A 'train' of SpaceX Starlink satellites,… Continue reading Effects of Large Satellite Constellations on Astronomy

The equinox 20 March 2022

In 2022 March 20 is the date of the March equinox and is also the first day of spring (or the first day of autumn if you're one of my readers in the Southern Hemisphere). In this post I’ll talk about the equinoxes and discuss the commonly held, but incorrect, view, that they are the… Continue reading The equinox 20 March 2022

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