The Oort cloud is theorised to be a vast cloud of icy bodies beyond the boundary of the Solar System. It was proposed by the Dutch astronomer Jan Oort back in 1950. Interestingly, the Estonian astronomer Ernst Opik had published a very similar idea in1931. However, Opik’s earlier work was largely ignored and today we… Continue reading The Oort Cloud
Tag: Science
eBooks from Explaining Science 2024
Update 30 August 2025 I have extensively expanded and rewritten all three “A Short Guide to…” e-books. I will make these books available on Kindle for a competitive price. However, in future I won’t do any deals where I offer free or discounted prices on these books for a limited time period. I believe the… Continue reading eBooks from Explaining Science 2024
Gliese 710: The Closest Future Star Encounter
Updated 21 November 2025 In this post I’ll talk about the star Gliese 710. In 1.3 million years’ time it is forecast to pass within 0.166 light years of the Solar System, 25 times closer than Proxima Centauri which is our current nearest star (excluding the Sun of course). The close approach of Gliese 710… Continue reading Gliese 710: The Closest Future Star Encounter
September 22 2024 – the equinox
In 2024 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, but not quite correct, view that they… Continue reading September 22 2024 – the equinox
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… Continue reading The Space Shuttle 10 years on
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