Updated 7 December 2025 Venus is, the planet closest to the Earth in size and internal composition, and the brightest natural object in the sky after the Sun and the Moon. This completly revised e-book covers most of the main areas about Venus. Why is it so bright? The 584-day cycle where Venus goes through… Continue reading e-book on Venus from Explaining Science
Tag: Space
The Rare Earth hypothesis
Updated 15 December 2025 Ever since the pioneering work of Frank Drake (1930-2022) way back in 1960, astronomers have been looking for radio signals from extraterrestrial civilisations but all SETI searches have failed to find anything. This could be because Earth-like planets containing complex life forms (such as ourselves) are rare in the Universe and only… Continue reading The Rare Earth hypothesis
American manned spaceflight in 2018?
This post has been superseded by the later post American spaceflight in 2019 As readers of a previous post will know, since the retirement of the Space Shuttle in July 2011, America has been unable to put any astronauts into orbit around the Earth. Instead, it has been reliant on the Russian Soyuz spacecraft to… Continue reading American manned spaceflight in 2018?
The early days of the space race
In my previous post I talked about two significant successes for the Soviet Union in 1957: the first artificial satellite in orbit in October and the first living creature, a dog named Laika, in orbit in November. In December of that year the Americans had a humiliating failure when the Vanguard spacecraft exploded in a… Continue reading The early days of the space race
4 October 1957 – the start of the space age
Updated 16 December 2025 On 4 October 1957, the Soviet Union launched the first artificial satellite, Sputnik 1, into orbit around the Earth. This is considered to be the beginning of the space age. Before this date there were no human made satellites in space but on every single day since then there have been artificial… Continue reading 4 October 1957 – the start of the space age
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