Portal:Spaceflight/Selected article/Week 23 2009
left|150px Project Daedalus was a study conducted between 1973 and 1978 by the British Interplanetary Society to design a plausible interstellar unmanned spacecraft. A dozen scientists and engineers led by Alan Bond worked on the project, and settled on proposing a fusion rocket as its drive. The design criteria had specified that the spacecraft had to use current or near-future technology and had to be able to reach its destination within a human lifetime (a flight time of 50 years was allocated). However, as noted above, it was not to be manned, being intended mainly as a scientific probe. The target chosen was Barnard's Star, 5.9 light years away, which at the time was believed to possess at least one planet (the evidence on which this belief was based has since been discredited). However, the design was required to be flexible enough that it could be sent to any of a number of other target stars. Daedalus was to be a two-stage spacecraft. The first stage would operate for two years, taking the spacecraft to 7.1% of light speed (0.071 c), and then after it was jettisoned the second stage would fire for 1.8 years, bringing the spacecraft up to about 12% of light speed (0.12 c) before being shut down for a 46-year cruise period. The ship's payload bay containing its sub-probes, telescopes, and other equipment would be protected from the interstellar medium during transit by a beryllium disk up to 7 mm thick and weighing up to 50 tonnes.