Virgin Galactic plans to resume spaceflights for wealthy customers at around $600,000 per flight, lasting 2.5 hours with only 5 minutes above 80 km. The definition of the boundary of space varies, with the Karman Line at 100 km supported by the FAI, while the FAA considers it at 80 km.
Tag: Space
e-book on Venus from Explaining Science
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
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This post has been superseded by the later post American spaceflight in 2019 As readers of a previous post will know, since the retirement of the Space Shuttle in July 2011, America has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
