For the reason that Nineteen Sixties, there was hypothesis a few hypothetical propulsion technique for interstellar house journey. Calculations at TU Wien (Vienna) present: it is going to stay science fiction.
In science fiction tales about contact with extraterrestrial civilizations, there’s a drawback: What sort of propulsion system might make it potential to bridge the big distances between the celebrities? It can’t be achieved with abnormal rockets like these used to journey to the moon or Mars. Many roughly speculative concepts about this have been put ahead — one in all them is the “Bussard collector” or “Ramjet propulsion.” It includes capturing protons in interstellar house after which utilizing them for a nuclear fusion reactor.
Peter Schattschneider, physicist and science fiction writer, has now analyzed this idea in additional element collectively together with his colleague Albert Jackson from the USA. The result’s sadly disappointing for followers of interstellar journey: it can not work the way in which Robert Bussard, the inventor of this propulsion system, thought it up in 1960. The evaluation has now been revealed within the scientific journal Acta Astronautica.
The hydrogen-collecting machine
“The thought is certainly price investigating,” says Prof. Peter Schattschneider. “In interstellar house, there may be extremely diluted fuel, primarily hydrogen — about one atom per cubic centimeter. Should you have been to gather the hydrogen in entrance of the spacecraft, like in a magnetic funnel, with the assistance of giant magnetic fields, you may use it to run a fusion reactor and speed up the spacecraft.” In 1960, Robert Bussard revealed a scientific paper about this. 9 years later, such a magnetic subject was described theoretically for the primary time. “Since then, the thought has not solely excited science fiction followers, however has additionally generated a substantial amount of curiosity within the technical and scientific astronautics neighborhood,” says Peter Schattschneider.
Peter Schattschneider and Albert Jackson now took a better take a look at the equations, half a century later. Software program developed at TU Wien as a part of a analysis challenge for calculating electromagnetic fields in electron microscopy unexpectedly turned out to be extraordinarily useful: the physicists have been ready to make use of it to point out that the fundamental precept of magnetic particle trapping really works. Particles may be collected within the proposed magnetic subject and guided right into a fusion reactor. On this manner, appreciable acceleration may be achieved — as much as relativistic speeds.
Nonetheless, when the dimensions of the magnetic funnel is calculated, hopes of a go to to our galactic neighbors rapidly fade. To realize a thrust of 10 million newtons — equal to twice the principle propulsion of the House Shuttle — the funnel must have a diameter of virtually 4000 kilometers. A technically superior civilization may have the ability to construct one thing like that, however the actual drawback is the required size of the magnetic fields: The funnel must be about 150 million kilometers lengthy — that’s the gap between the solar and the earth.
So after half a century of hope for interstellar journey within the distant future, it’s now obvious that the ramjet drive, whereas an attention-grabbing thought, will stay merely a part of science fiction. If we wish to go to our cosmic neighbors sooner or later, we must provide you with one thing else.
Reference: “The Fishback ramjet revisited” by Peter Schattschneider and Albert A. Jackson, 15 November 2021, Acta Astronautica.