There are extended daylight hours and twilight periods during summer at northern latitudes The article focusses on Manchester and Shetland. It defines twilight and its three stages, highlights the Sun's path at various times of the year, and explains the phenomenon of "Simmer Dim" in Shetland and the celebrations associated with these light nights.
In March 2019 the American Vice President Mike Pence surprised many people when he announced an extremely ambitious plan to put American astronauts on the Moon in 2024. NASA named its new crewed Moon programme Artemis, after Apollo’s sister in Greek mythology. Perhaps unsurprisingly, the dates have slipped since this extremely ambitious announcement. After numerous… Continue reading NASA’s Artemis Moon Missions
The Oort Cloud, theorized by Jan Oort in 1950, is a vast, icy structure beyond the Solar System, containing trillions of objects. It is divided into the sparse outer cloud and the denser, doughnut-shaped inner cloud. Evidence for its existence includes the orbits of long-period comets. Galactic tides and interactions with giant planets likely contributed to its formation and distribution of icy bodies.
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
Updated 21 November 2025 In 1.3 million years’ time the star Gliese 710 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 will be the strongest disrupting encounter known… Continue reading Gliese 710: The Closest Future Star Encounter
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