20 July 2019 is the fiftieth anniversary of the first manned landing on the Moon. Mission Insignia of Apollo 11- Image from NASA On 21 May 1961 President John F Kennedy made the following address to the United States Congress: 'I believe that this nation should commit itself to achieving the goal, before this decade… Continue reading Apollo 11 lunar landing
Author: Steve Hurley
Summer twilight
This explains the stages of twilight , and describes how the Sun's path changes throughout the year in Manchester, England. The phenomenon of "Simmer Dim" in the Shetland Islands is highlighted, characterized by continuous twilight and celebrated with a festival.
e-book from Explaining Science on Venus
Updated 7 December 2025 I have now updated my e-book on Venus, the planet closest to the Earth in distance, size and internal composition, and the third brightest natural object in our sky after the Sun and the Moon. Topics include how Venus appears from Earth and the fact that Venus’s phases can only be… Continue reading e-book from Explaining Science on Venus
The Impact of Stellar Aberration on Astronomy
Solar energy costs
In a previous post I talked about the advantages of solar electricity compared to other renewable source of electricity. In this post I’ll move away from my normal scientific topics and discuss the costs of small scale solar energy and how it compares with other renewables. Whats is 'the LCOE'? When comparing the relative costs… Continue reading Solar energy costs


