This was a thirteen member volunteer engineering design study conducted between 1973 and 1978, to demonstrate that Interstellar travel is feasible in theory. The project related to the Fermi Paradox first postulated by the Italian Physicist Enrico Fermi in the 1940s. This supposes that there has been plenty of time for intelligent civilizations to interact within our galaxy when one examines the age and number of stars, as well as the distances between them. Yet, the fact that extra-terrestrial intelligence has never been observed leads to a logical paradox where our observations are inconsistent with our theoretical expectation. This original question from Fermi seemed to also reinforce the prevailing paradigm at the time that interstellar travel was impossible. Project Daedalus was a bold way to examine the Fermi Paradox head on and gave a partial answer – interstellar travel is possible. The basis of this belief was the demonstration of a credible engineering design just at the outset of the space age that could in theory, cross the interstellar distances. In the future scientific advancement would lead to a refined and more efficient design. The absence of alien visitors would therefore require a different explanation because Project Daedalus demonstrated that with current, and near future, technology, interstellar travel is feasible. Therefore, another solution to the absence of extra-terrestrial visitation was necessary.
There were three stated goals for Project Daedalus:
- (1) The spacecraft must use current or near-future technology
- (2) The spacecraft must reach its destination within a working human lifetime
- (3)The spacecraft must be designed to allow for a variety of target stars. The final design solution was published in a special supplement of the Journal of the British Interplanetary Society in 1978.
The two-stage engine configuration was powered by inertial confinement fusion using deuterium and helium-3 pellets. Electron beam diodes positioned around the base of the engine exhaust would impinge on the pellets and ignite them to produce large energy gain, at a rate of 250 detonations per second. This would continue for a boost phase lasting over 3.8 years followed by a cruise phase lasting 46 years and travelling at over 12% of the speed of light until the 450 tons science probe would finally reach its destination of the Barnard’s Star system 5.9 light years away, which it would transit in a matter of days due to its flyby nature.
In the final study reports all of the main vehicle systems were considered including the structure, communications, navigation and the deployment of mitigation sub-systems to deal with the bombardment of interstellar dust. The pedigree for Project Daedalus derives directly from 1950-1960s Project Orion, a vehicle that used Atomic and Hydrogen bombs to propel the spacecraft. The main issue with Orion however was the existence of several nuclear test ban treaties which forbid the use or testing of such technology. Project Daedalus proposed to shrink this technology down to the size of pocket coins but still take advantage of the enormous energy release from a fusion based fuel.
The Project Daedalus study was primarily led by Alan Bond, Tony Martin and Bob Parkinson and even today the study distinguishes itself from all other studies as the most complete engineering study ever undertaken for an interstellar probe. Even if Daedalus is not the template for how our robotic ambassadors will someday reach the distant stars, at the very least it will be a crucial part of the journey for getting to that first launch. Rigorous engineering assessments are the only way to provide reliable information on what is possible today or in the near-future.
More about the history of the BIS project Daedalus can be found in the recent republication book, which can be purchased here: Project Daedalus: Demonstrating the Engineering Feasibility of Interstellar Travel.