Art Sketch: a Mars manned spacecraft powered by a fusion energy rocket. In this image, the astronauts will be seated in the forward cabin of the spacecraft. The energy collected by the solar panels on both sides will be used to provide the initial energy for triggering nuclear fusion.
Plasma (blue in the picture) is being injected into the rocket nozzle. Then the lithium metal (red) is contracted instantaneously, forming a huge pressure on the plasma in the central space, triggering the nuclear fusion reaction. This instantaneous fusion reaction releases huge energy to heat and cause the lithium metal shell to evaporate and ionize, and eject from the rocket nozzle at high speed to produce forward propulsion.
This is the fusion rocket test module of the plasma Dynamics Laboratory at the University of Washington. The green vacuum chamber in the picture is wrapped by two large high-strength aluminum magnets. The electromagnet system is powered by a powerful capacitor, and a large number of wires are connected to each system.
According to the website of American physicists organization, manned Mars exploration has long been a seemingly distant dream. But now, astronomers may have taken another step towards this goal: they have developed a unique fusion propulsion technology, which is the same mechanism that drives the sun and stars to glow and heat.
The University of Washington and the space propulsion technology company in Redmond are working to develop a new type of fusion driven rocket. The successful development of the rocket will clear a series of obstacles in the way of manned Mars exploration, including long-time space flight, high cost and health risks.
John slough, an assistant professor of Aeronautics and Astronautics at the University of Washington, who is the main researcher of the project, said: 'it is almost impossible to support human deep space exploration flight far away from the earth with the existing rocket propulsion fuel. He said: 'we hope to get a rocket fuel that is far more efficient than it is now, so that we can finally achieve manned star trek. '
An expensive trip to Mars
The project is funded by NASA's innovative advanced concept project. At a seminar held last week, sloe and his team presented their analysis of manned flight on Mars, as well as detailed computer modeling analysis and preliminary experimental results. SLO's research project received a second round of funding from NASA last fall. Initially, about 700 projects participated in NASA's funding applications, and finally 15 projects received the first round of funding support. Now the sloe team's projects have passed the evaluation again and received the second round of funding support.
NASA estimates that based on existing technology, it will take at least four years for a manned mission to and from Mars. So the amount of chemical fuel and money that's going to be spent in the whole process is going to be amazing - 12 billion dollars for light emission. Sloe and his team have published their latest calculations in the journal, assessing the cost of a new fusion rocket to and from Mars, assuming it takes 30 or 90 days, respectively. With the use of nuclear fusion technology, manned flight on Mars will become more practical and economical.
Technical feasibility
But can this technology really be realized? Sloe and his team believe the answer is yes. They have tested the whole process in the laboratory. Now the problem they are facing is to combine these separate component experiments together to carry out the overall experiment, and actually test the technical scheme of nuclear fusion. The team has developed a special kind of plasma, which is bound by its own magnetic field. When these plasmas are strongly compressed in a magnetic field, nuclear fusion occurs. Previously, the experimental team has successfully verified the technology in the laboratory.
It takes very little fusion fuel to drive a rocket. A grain of sand is as powerful as a gallon of ordinary chemical dye. In order to promote nuclear fusion, the research group uses metal ring implosion around the plasma in the magnetic field to exert a strong centripetal pressure on the plasma and then initiate nuclear fusion. The surrounding metal rings form a shell that triggers fusion, but only for a few microseconds. But even with such a short compression time, the fusion is enough to generate enough energy to heat rapidly and cause the shell to ionize. At this time, the metal shell evaporated at ultra-high temperature will be ejected out of the rocket nozzle at high speed to push the rocket forward. This process is repeated about every minute, driving the rocket to accelerate continuously.
The team has demonstrated this fusion propulsion technology based on metal loss at the plasma Dynamics Laboratory at the University of Washington. At a recent NASA seminar, the team also showed a fist sized aluminum metal ball, which is the remaining metal in the test of this reaction mechanism. This little ball can be touched and watched. "I think you are very happy to see that our proposal for nuclear fusion using compressed plasma has proved to be effective in the demonstration," said SLO. He said: 'we hope that the world will pay attention to the technology we are showing, and let people understand that nuclear fusion technology does not have to wait 40 years to be applied, and the cost of applying this technology does not need to spend $2 billion. '
A new round of testing
Now, the team is working to integrate the process of plasma compression and the mechanism of nuclear fusion. Sloe hopes to be ready for the first overall test at the end of this summer. The plasma dynamics lab where SLO and his colleagues do all kinds of experiments is full of capacitors, which are containers of energy, like high-energy batteries.
These capacitors are connected to a huge magnet, together with other facilities, to form the equipment for nuclear fusion reaction. When the switch is activated, the capacitor will instantly release more than 1 million amperes of current to the magnet system, causing the latter to produce sharp compression on the metal shell. The design of the whole device is very simple and clear, sloe said: 'in space, all parts must be as simple as possible. In actual space missions, scientists will use lithium as a metal shell to propel the rocket. Lithium is chosen because it is a very active metallic substance. For the early laboratory test, aluminum is enough.
SLO said that when it comes to the topic of nuclear fusion, people will have some concerns, because it reminds people of nuclear weapons, but its application in other areas is a very different concept. The fusion energy used to propel the rocket is a billion times smaller than that of hydrogen bomb explosion. This kind of fusion can not cause significant explosion. In addition, sloe's design also includes the use of a strong magnetic field to restrain the product of nuclear fusion reaction, so that it can leave the rocket and prevent it from harming any crew in the spacecraft.