The solar system is really a great place and it takes forever to travel from the world to the world with traditional chemical missiles. But a technique developed in the 1960s can provide a way to drastically shorten travel time: nuclear missiles.
Of course, launching a rocket fed by radioactive material also has its own risks. Let's say you want to visit Mars with a chemical missile. You will get rid of the Earth and you will go in low orbit on Earth. Then, at the right time, you will fire your rocket, raising your orbit from the Sun. The new elliptical trajectory you are following intersects with Mars after eight months of flight.
This is known as Hohen's transfer, and this is the most effective way to know how to travel in space using the smallest amount of propellant and the greatest payload. The problem, of course, is the time it takes. During the journey, astronauts will consume food, water, and air, and will be exposed to long-term radiation of deep space. The return mission then doubles the need for resources and doubles the radiation load
. Credit: NASA
We have to go faster.
It turns out that NASA is thinking about what's coming after the chemical missiles for nearly 50 years. Nuclear thermal missiles. They definitely speed up the journey, but they are not without their own risks, so you have not seen them. But maybe their time is here.
In 1961, NASA and the Nuclear Energy Commission worked together on the idea of Nuclear Heat Propulsion or NTP. This is a pioneer from Werner von Braun, who hopes that human missions will fly to Mars in the 1980s on the wings of nuclear missiles.
Well, that did not happen. But they have done some successful tests of the nuclear thermal propulsion and have shown that it works well.
The artist's concept of a bimodal nuclear thermal missile in low Earth orbit. While a chemical rocket works by igniting some kind of flammable chemicals and then ejecting the exhaust from the nozzle. Thanks to the third law of Good Old Newton, you know, for each action there is an identical and opposite reaction, the rocket gets the backward thrust from the exhaust.
Nuclear rocket works in a similar way. A marble ball of uranium fuel undergoes a process of fission, releasing a huge amount of heat. It heats hydrogen to almost 2500 C, which is then thrown out of the back of the rocket at high speed. Very high speed, which gives the rocket two to three times the efficiency of the chemical missile propulsion.
Do you remember the 8 months I mentioned as a chemical rocket? The nuclear thermal missile can reduce transit time in half, maybe even 100 day trips to Mars. Which means less resources used by astronauts and lower radiation load.
And there is another big benefit. Targeting a nuclear missile can allow missions to go when Earth and Mars are not fully aligned. At the moment, if you skip the window, you have to wait another 2 years, but the nuclear missile can give you a boost to cope with flight delays.
The first nuclear missile tests began in 1955 with Project Rover in Los Alamos. Scientific Laboratory. The key development was miniaturization of the reactors enough to be able to be placed on a rocket. In the next few years, engineers designed and tested more than a dozen reactors of different sizes and power
The first ground-run experimental nuclear missile engine (XE) in cold flow configuration is shown as being installed in the Engine Development Test Drive No. 1 of the nuclear missile at Jackass Flats, Nevada.
With Project Rover's success, NASA focused its attention on the human missions to Mars, which would follow Apollo's moon landings. Because of the distance and flight times, they decided that nuclear missiles would be the key to better missions.
Nuclear missiles, of course, are not without risks. A reactor on board will be a small source of radiation for the crew of astronauts on board, this will be overcome by reduced flight time. Deep space itself is a huge radiation hazard, with constant galactic cosmic radiation damaging astronaut DNA.
At the end of the 1960s, NASA set up a Nuclear Powertrain Program (NERVA) for nuclear rocket engines or NERVA to develop nuclear technology
NASA Design for a Nuclear Missile Engine (NERVA). They were testing larger, more powerful nuclear missiles in the Nevada desert, releasing hydrogen gas at high speed directly into the atmosphere. Environmental laws were much less stringent then.
The first NERVA NRX has been tested for almost two hours, with 28 minutes at full power. The second engine runs 28 times and lasts 115 minutes.
After all, they test the most powerful nuclear reactor ever built – the Phoebus-2A reactor, which can generate 4,000 megawatts of power. For 12 minutes. Although the various components were never assembled into a ready-to-fly missile, engineers are pleased that the nuclear missile will meet the needs of a flight to Mars.
But then the US decided I no longer wanted to go to Mars. Instead they wanted a space shuttle.
Space Shuttle Atlantis ends the shuttle with an early return to the Kennedy Space Center in Florida. The program was closed in 1973 and since then no one has tested nuclear missiles.
New advances in technology make nuclear thermal engines more attractive. In the 1960s, the only source of fuel they could use was highly enriched uranium. But now engineers think they can deal with low-enriched uranium. It would be safer to work with, and allow more rocket gear to conduct tests. It would also be easier to capture the radioactive particles in the exhaust pipe and to dispose of them properly. This will reduce total technology costs
On May 22, 2019, the US Congress approved $ 125 million to fund the development of nuclear power-driven missiles. While this program does not play any role in NASA's Artemida 2024, returning to the moon, she quotes, "calls on NASA to develop a multi-year plan that allows demonstration of nuclear thermal propulsion, including the space-time demonstration line. and a description of future missions and engines and power systems that are permitted by this capability. "
Nuclear fission is one way to harness the power of the atom. Of course, it requires enriched uranium and generates toxic radioactive waste. What about the merger? Where are the atoms of hydrogen pressed into helium, releasing energy?
Our Sun is a star of population II about 5 billion years ago. It contains elements heavier than hydrogen and helium, including oxygen, carbon, neon and iron, albeit only in small percentages. Photo: NASA / Solar Dynamics Observatory.
The sun has made the merger, thanks to its mass and core temperature, but the steady, energetically positive merger has been elusive to us with slimy people.
Huge experiments such as ITER in Europe are hoping to keep fusion energy within the next decade. Then you can imagine that nuclear fusion reactors will be miniaturized to such an extent that they can perform the same role as a nuclear rocket fission reactor. But even if you can not get thermonuclear reactors to the extent that they are pure energy, they can still provide massive mass acceleration.
Building the ITER Fusion Facility in Europe. Credit: ITER
And maybe we do not have to wait for decades. A research group at the Princeton Plasma Physics Lab is working on a concept called Direct Fusion Drive, which they think could be done much earlier.
It is based on the Princeton Fission Reactor, developed in 2002 by Samuel Cohen. Hot plasma of helium-3 and deuterium are contained in a magnetic container. Helium-3 is rare on Earth and is valuable because the synthesis reactions with it will not generate the same amount of hazardous radiation or nuclear waste as other reactors for synthesis or fission.
Like the fission missile, the fusion rocket also heats the propellant to high temperatures and then breaks it on the back, producing the thrust. and very hot plasma rotates. Plasma antennas are tuned to the specific frequency of ions and generate plasma current. Their energy is pumped to the point where the atoms merge, releasing new particles. These particles travel through the protective field until they are caught by the magnetic field and they accelerate from the back of the rocket. with a specific pulse of 10,000 seconds – remember 850 of the fission missiles and 450 of the chemical missiles. It will also generate the electricity needed by the spacecraft away from the Sun, where solar panels are not very effective. spacecraft from Earth to Pluto for about 4 years. New horizons needed nearly 10.
Since it is also a 1 megawatt thermonuclear reactor, it would also provide energy for all spacecraft tools when it arrives. Much more than the nuclear batteries that are currently being carried out by deep space missions like Voyager and New Horizons.
Imagine what kinds of interstellar missions can be on the table and with this technology.
And Princeton satellite systems are not the only group working on such systems. Applied Fusion Systems have applied for a nuclear fusion patent that can provide spacecraft.
I know that for decades since NASA has seriously tested nuclear missiles as a way to shorten flight times, it seems the technology has returned. Over the next few years I expect to see new hardware and new tests of nuclear thermal systems. And I'm incredibly excited about the possibility that the actual fuzz will take us to other worlds. As always, stay in line, I'll let you know when it's actually flying.