Project Daedalus
Encyclopedia
Project Daedalus was a study conducted between 1973 and 1978 by the British Interplanetary Society
British Interplanetary Society
The British Interplanetary Society founded in 1933 by Philip E. Cleator, is the oldest space advocacy organisation in the world whose aim is exclusively to support and promote astronautics and space exploration.-Structure:...

 to design a plausible unmanned
Unmanned spacecraft
Unmanned spacecraft are spacecraft without people on board, and probably includes unmanned resupply spacecraft, space probes, and most space observatories. A difference between robotic spacecraft and unmanned spacecraft, is that unmanned spacecraft is inclusive to non-robotic unmanned spacecraft,...

 interstellar spacecraft. Intended mainly as a scientific probe, the design criteria 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. Alan Bond
Alan Bond (rocket developer)
Alan Bond is Managing Director of Reaction Engines Ltd and associated with Project Daedalus, Blue Streak missile, HOTOL, Reaction Engines Skylon and the Reaction Engines A2 hypersonic passenger aircraft.- Career :...

 led a team of scientists and engineers who proposed using a fusion rocket
Fusion rocket
A fusion rocket is a theoretical design for a rocket driven by fusion power which could provide efficient and long-term acceleration in space without the need to carry a large fuel supply. The design relies on the development of fusion power technology beyond current capabilities, and the...

 to reach Barnard's Star
Barnard's star
Barnard's Star, also known occasionally as Barnard's "Runaway" Star, is a very low-mass red dwarf star approximately six light-years away from Earth in the constellation of Ophiuchus . In 1916, the American astronomer E.E...

, only 5.9 light years away. The trip was estimated to take 50 years, but the design was required to be flexible enough that it could be sent to any of a number of other target stars.

Concept

Daedalus would be constructed in Earth orbit and have an initial mass of 54,000 tonnes, including 50,000 tonnes of fuel and 500 tonnes of scientific payload. 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. Due to the extreme temperature range of operation required (from near absolute zero to 1,600 K) the engine bells and support structure would be made of molybdenum
Molybdenum
Molybdenum , is a Group 6 chemical element with the symbol Mo and atomic number 42. The name is from Neo-Latin Molybdaenum, from Ancient Greek , meaning lead, itself proposed as a loanword from Anatolian Luvian and Lydian languages, since its ores were confused with lead ores...

 TZM alloy
Alloy
An alloy is a mixture or metallic solid solution composed of two or more elements. Complete solid solution alloys give single solid phase microstructure, while partial solutions give two or more phases that may or may not be homogeneous in distribution, depending on thermal history...

, which retains strength even at cryogenic temperatures. A major stimulus for the project was Friedwardt Winterberg
Friedwardt Winterberg
Friedwardt Winterberg is a German-American theoretical physicist and research professor at the University of Nevada, Reno. With more than 260 publications and three books, he is known for his research in areas spanning general relativity, Planck scale physics, nuclear fusion, and plasmas...

's inertial confinement fusion
Inertial confinement fusion
Inertial confinement fusion is a process where nuclear fusion reactions are initiated by heating and compressing a fuel target, typically in the form of a pellet that most often contains a mixture of deuterium and tritium....

 drive concept for which he received the Hermann Oberth gold medal award.

This velocity is well beyond the capabilities of chemical rockets, or even the type of nuclear pulse propulsion
Nuclear pulse propulsion
Nuclear pulse propulsion is a proposed method of spacecraft propulsion that uses nuclear explosions for thrust. It was first developed as Project Orion by DARPA, after a suggestion by Stanislaw Ulam in 1947...

 studied during Project Orion
Project Orion (nuclear propulsion)
Project Orion was a study of a spacecraft intended to be directly propelled by a series of explosions of atomic bombs behind the craft...

. Instead, Daedalus would be propelled by a fusion rocket
Fusion rocket
A fusion rocket is a theoretical design for a rocket driven by fusion power which could provide efficient and long-term acceleration in space without the need to carry a large fuel supply. The design relies on the development of fusion power technology beyond current capabilities, and the...

 using pellets of deuterium
Deuterium
Deuterium, also called heavy hydrogen, is one of two stable isotopes of hydrogen. It has a natural abundance in Earth's oceans of about one atom in of hydrogen . Deuterium accounts for approximately 0.0156% of all naturally occurring hydrogen in Earth's oceans, while the most common isotope ...

/helium-3
Helium-3
Helium-3 is a light, non-radioactive isotope of helium with two protons and one neutron. It is rare on Earth, and is sought for use in nuclear fusion research...

 mix that would be ignited in the reaction chamber by inertial confinement
Inertial confinement fusion
Inertial confinement fusion is a process where nuclear fusion reactions are initiated by heating and compressing a fuel target, typically in the form of a pellet that most often contains a mixture of deuterium and tritium....

 using electron beams. The electron beam system would be powered by a set of induction coils tapping energy from the plasma
Plasma (physics)
In physics and chemistry, plasma is a state of matter similar to gas in which a certain portion of the particles are ionized. Heating a gas may ionize its molecules or atoms , thus turning it into a plasma, which contains charged particles: positive ions and negative electrons or ions...

 exhaust stream. 250 pellets would be detonated per second, and the resulting plasma
Plasma (physics)
In physics and chemistry, plasma is a state of matter similar to gas in which a certain portion of the particles are ionized. Heating a gas may ionize its molecules or atoms , thus turning it into a plasma, which contains charged particles: positive ions and negative electrons or ions...

 would be directed by a magnetic nozzle. The computed burn-up fraction for the fusion fuels was 0.175 and 0.133 for the First & Second stages, producing exhaust velocities of 10,600 km/s and 9,210 km/s, respectively. Due to the scarcity of helium-3
Helium-3
Helium-3 is a light, non-radioactive isotope of helium with two protons and one neutron. It is rare on Earth, and is sought for use in nuclear fusion research...

 it was to be mined from the atmosphere of Jupiter
Jupiter
Jupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with mass one-thousandth that of the Sun but is two and a half times the mass of all the other planets in our Solar System combined. Jupiter is classified as a gas giant along with Saturn,...

 via large hot-air balloon supported robotic factories over a 20 year period.

The second stage would have two 5-meter optical telescope
Optical telescope
An optical telescope is a telescope which is used to gather and focus light mainly from the visible part of the electromagnetic spectrum for directly viewing a magnified image for making a photograph, or collecting data through electronic image sensors....

s and two 20-meter radio telescope
Radio telescope
A radio telescope is a form of directional radio antenna used in radio astronomy. The same types of antennas are also used in tracking and collecting data from satellites and space probes...

s. About 25 years after launch these telescopes would begin examining the area around Barnard's Star to learn more about any accompanying planets. This information would be sent back to Earth, using the 40-meter diameter second stage engine bell as a communications dish, and targets of interest would be selected. Since the spacecraft would not decelerate upon reaching Barnard's Star, Daedalus would carry 18 autonomous sub-probes that would be launched between 7.2 and 1.8 years before the main craft entered the target system. These sub-probes would be propelled by nuclear-powered
Nuclear electric rocket
In a nuclear electric rocket, nuclear thermal energy is changed into electrical energy that is used to power one of the electrical propulsion technologies. Technically the powerplant is nuclear, not the propulsion system, but the terminology is standard. A number of heat-to-electricity schemes...

 ion drives and carry cameras, spectrometer
Spectrometer
A spectrometer is an instrument used to measure properties of light over a specific portion of the electromagnetic spectrum, typically used in spectroscopic analysis to identify materials. The variable measured is most often the light's intensity but could also, for instance, be the polarization...

s, and other sensory equipment. They would fly past their targets, still travelling at 12% of the speed of light, and transmit their findings back to the Daedalus second stage mothership for relay back to Earth.

The ship's payload bay containing its sub-probes, telescopes, and other equipment would be protected from the interstellar medium
Interstellar medium
In astronomy, the interstellar medium is the matter that exists in the space between the star systems in a galaxy. This matter includes gas in ionic, atomic, and molecular form, dust, and cosmic rays. It fills interstellar space and blends smoothly into the surrounding intergalactic space...

 during transit by a beryllium
Beryllium
Beryllium is the chemical element with the symbol Be and atomic number 4. It is a divalent element which occurs naturally only in combination with other elements in minerals. Notable gemstones which contain beryllium include beryl and chrysoberyl...

 disk up to 7 mm thick and weighing up to 50 tonnes. This erosion shield would be made from beryllium due to its lightness and high latent heat of vaporisation. Larger obstacles that might be encountered while passing through the target system would be dispersed by an artificially generated cloud of particles, ejected by support vehicles called dust bugs, some 200 km ahead of the vehicle. The spacecraft would carry a number of robot
Robot
A robot is a mechanical or virtual intelligent agent that can perform tasks automatically or with guidance, typically by remote control. In practice a robot is usually an electro-mechanical machine that is guided by computer and electronic programming. Robots can be autonomous, semi-autonomous or...

 "wardens" capable of autonomously repairing damage or malfunctions.

Specifications

  • Overall length: 190 metres
  • Propellant mass first stage: 46,000 tonnes
  • Propellant mass second stage: 4,000 tonnes
  • First stage empty mass at staging: 1,690 tonnes
  • Second stage mass at cruise speed: 980 tonnes
  • Engine burn time first stage: 2.05 years
  • Engine burn time second stage: 1.76 years
  • Thrust first stage: 7,540,000 newtons
  • Thrust second stage: 663,000 newtons
  • Engine exhaust velocity: 10,600,000 m/s & 9,210,000 m/s
  • Payload mass: 450 tonnes

Variants

A quantitative engineering analysis of a self-replicating variation on Project Daedalus was published in 1980 by Robert Freitas
Robert Freitas
Robert A. Freitas Jr. is a Senior Research Fellow, one of four researchers at the nonprofit foundation Institute for Molecular Manufacturing in Palo Alto, California. He holds a 1974 Bachelor's degree majoring in both physics and psychology from Harvey Mudd College, and a 1978 Juris Doctor degree...

. The non-replicating design was modified to include all subsystems necessary for self-replication, using the probe to deliver a "seed" factory with a mass of about 443 metric tons to a distant site, having the seed factory replicate many copies of itself there to increase its total manufacturing capacity, and then using the resulting automated industrial complex to construct more probes with a single seed factory on board each over a 1,000 year period. Each REPRO would mass over 10 million tons, mostly fuel needed to decelerate from 12% of lightspeed.

See also

  • Project Longshot
    Project Longshot
    Project Longshot was a conceptual design for an interstellar spacecraft, an unmanned probe intended to fly to Alpha Centauri powered by nuclear pulse propulsion. Developed by the US Naval Academy and NASA from 1987 to 1988, Longshot was designed to be built at Space Station Freedom, the precursor...

  • British Rail flying saucer
    British Rail flying saucer
    The British Rail flying saucer, officially known simply as space vehicle, was a proposed spacecraft designed by Charles Osmond Frederick.- Purpose :The flying saucer originally started as a proposal for a lifting platform...

  • Magnetic sail
    Magnetic sail
    A magnetic sail or magsail is a proposed method of spacecraft propulsion which would use a static magnetic field to deflect charged particles radiated by the Sun as a plasma wind, and thus impart momentum to accelerate the spacecraft...

  • Project Icarus
    Project Icarus (Interstellar Probe Design Study)
    Project Icarus is a theoretical design study aimed at designing a credible nuclear fusion-based interstellar spacecraft that will stand as a blueprint for a possible unmanned mission...


External links

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