These are some of my cosmology posts
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Daylight Saving Time ends
In the early hours of Sunday 31 October the clocks go back an hour throughout most of Europe and daylight saving time (DST) comes to an end. In this post I’ll talk about the practice of putting the clocks backwards and forwards and why this may be coming to an end The beginning of DST…
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Opportunities for solar energy
In 2019, the year before the restrictions of the covid-19 pandemic, the world energy consumption was slightly higher at around 170 000 TWh. In this post I will talk about some of the science behind this amazing fact and discuss the challenge of getting solar energy from where it is plentiful to where it is…
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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…
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The Perseids 2021
The night of 12/13 August will be the peak of the Perseids, one of the most famous prolific meteor showers. Meteors (also known as shooting stars) are bright streaks of light caused by small lumps of rock or metal called meteoroids hitting the Earth’s atmosphere at very high speed (in the case of the Perseids around 200,000 km/h).…
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Congratulations Blue Origin!
A week is certainly a long time in crewed spaceflight! Following Richard Branson’s trip to “the edge of space” on Sunday 11 July, Jeff Bezos went one step further on July 20. He made a short journey to space, in the first crewed flight of his Blue Origin rocket ship, New Shepard. As the spacecraft…
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Congratulations Virgin Galactic
Great news from Virgin Galactic on Sunday. Although according to the widely used definition, their spacecraft didn’t quite get into space. Most international authorities define that space begins at an altitude of 100 km (the Karman line), whereas VSS Unity reached an altitude of 86 km, but a fantastic achievement nevertheless !!. For those who…
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The Space Shuttle 10 years on
Ten years ago, on 8 July 2011 Atlantis took off for the final mission of a Space Shuttle, bringing to close a programme which had lasted nearly 40 years and had cost the equivalent of $220 billion in 2021 dollars. In this post I’ll review this fascinating and unique piece of technology. The landing of…
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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…
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Satellite Navigation
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…
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The Observable Universe and Its Horizons
Updated March 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 a much larger region the unobservable universe…
Explaining Science 