At 0100 UTC (2 AM local time) on Sunday 26 October, the UK like most of Europe will put it clocks back by one hour at is comes to an end of Daylight Saving Time. Most of the USA will follow a week later. In this post I'll give an overview of DST and why… Continue reading The Clocks go Back 26 October 2025
Author: Steve Hurley
Solar Sails: Fuel-Free Space Travel
Solar sails are the only method of spacecraft propulsion in which no fuel is needed. Until recently spacecraft powered by solar sails were the stuff of science fiction. However, following the success of the Japanese spacecraft IKAROS in 2010 the crowd-funded Light Sail 2 spacecraft in 2019 and NASA's ACS3 in 2024, spacecraft powered by… Continue reading Solar Sails: Fuel-Free Space Travel
How we can see some of the Moon’s far side
Lunar libration is a 'wobble' caused mainly by the Moon’s elliptical orbit and axial tilt. It allows us to see about 59% of the Moon's surface over time, effectively revealing 18% of the 'far side' that would otherwise be hidden. This post discusses this interesting phenomenon. Updated 7 January 2026 Many people think that the… Continue reading How we can see some of the Moon’s far side
Lunar Stationary Orbits: Why They are Impossible
A friend of mine recently asked me whether it was possible to have a lunar-stationary orbit. This would be the equivalent of a geostationary orbit, but around the Moon rather than the Earth. To an observer on the Moon, a lunar-stationary satellite would appear fixed in the sky and if a dish were pointed… Continue reading Lunar Stationary Orbits: Why They are Impossible
Latitude and Longitude on the Moon and the Planets
This post discusses the use of latitude and longitude for mapping locations on the Moon and other celestial bodies in the Solar System. It explains how these coordinates are defined, the arbitrary selection of prime meridians, and variations across different planets, emphasizing the importance of consistent astronomical conventions for navigation and mapping.





