Updated 7 December 2025 The ashen light is a faint glow, which many people claim to have seen on the night side of Venus. The Italian astronomer Giovanni Riccioli (1598 -1671) first reported it back in 1643, 33 years after Galileo had made the first observations of Venus with a telescope and discovered the planet… Continue reading The Mystery of the Ashen Light of Venus
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
Anybody who has observed the eastern sky just before sunrise in the last few weeks will have noticed a brilliant white object - the planet Venus, also known as the morning star. It is brighter than any other planet and at its brightest ten times brighter than Sirius the brightest star. Its brightness has often… Continue reading Venus the Morning Star
Back in 2019, the year before the pandemic, many of you will have seen images of long ‘trains’ composed of up to sixty SpaceX Starlink satellites crossing the sky in a straight line. These pictures hit the headlines not only because of the number of satellites, but because of their brightness. A 'train' of… Continue reading Starlink and other Large Satellite Constellations
Updated 16 December 2015 It is more than 68 years since the launch of Sputnik 2 on November 3 1957 by the Soviet Union. It was only the second spacecraft to go into space and followed the successful launch of Sputnik 1 in October 1957. Sputnik 1 was a small metal sphere whose only piece… Continue reading Sputnik 2
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