A team of researchers, including engineers from the Los Alamos National Laboratory, this week reported their successful demonstration of a new concept that could provide reliable nuclear power for space exploration. The technology is still years away from the warp drive of Star Trek, but it could provide a means of propulsion for space travel beyond the moon.
The research team demonstrated the first use of a heat pipe to cool a small nuclear reactor and power a Stirling engine at the Nevada National Security Site’s Device Assembly Facility near Las Vegas. The Demonstration Using Flattop Fissions (DUFF) was the first use of a space nuclear reactor system to produce electricity in the United States since 1965.
“This is really a new old system, as it is a new platform build on an old technology,” said Michael Podowski, Ph.D., professor of nuclear engineering at Rensselaer Polytechnic Institute.
“The Stirling engine is an old one,” he pointed out, but “the concept is very healthy. The nuclear factor is not an issue at this point. However, [achieving] efficiency will require a lot more work.
“While the concept is interesting and it makes good use of the elements involved,” Podowski told TechNewsWorld, “it will require more work. It is as simple as that.”
To the Final Frontier
Although progress in manned space exploration beyond Earth’s orbit is not progressing at light speed, there are several projects in the works, and DUFF is just one of many possibilities for getting from here to way out there.
“In general, development of effective and reliable Stirling generators — known as dynamic systems that use mechanically moving parts — could become very important for long duration space flight as an effective way of producing electrical power,” said Michael Gruntman, Ph.D., professor of aerospace engineering and systems architecture engineering at the University of Southern California.
“A lot of work is going on in this area,” he told TechNewsWorld.
This is especially necessary because getting there will require serious power.
“Space exploration requires a long-term energy source,” said Podowski. “Nuclear reactors are certainly the future of space exploration as there are no other sources of energy for such long-distance travel.”
Not Quite Warp Speed
Even with this technology — or something similar to DUFF — it won’t mean getting there at science fiction-worthy speeds. However, it certainly can provide a means to go farther than anything previously available.
“We could have a nuclear-powered rocket that could get to Pluto in two years; whereas a chemical rocket would take seven years,” said Paul Czysz, Ph.D., professor of aeronautical engineering at Parks College.
“We think it is the enabling technology,” he told TechNewsWorld. “If you are really going to do something on this scale, you need to have something other than chemical rockets.”
More importantly, this technology could be what is required to simply get beyond the moon, which remains the farthest point of manned space exploration. Even our closest neighbor, Mars, is considered too far for humans to successfully travel to and return.
“For man’s exploration to Mars with current chemical solutions, you will only get as many astronauts to go [as are willing] to come back as dead bodies. During the trip you’d get a healthy dose of radiation, so it would be necessary to reduce the time in travel,” Czysz explained.
“Nuclear powered space exploration is the only way to get a sizable crew to Mars and provide them with enough resources to survive a year,” he added.
Rockets Go Nuclear
While the DUFF experiment is based on older technology, revisiting it may be the key to future space travel for numerous reasons.
“The key advantages seem to be its ease of manufacture, the fact that materials are readily available within the U.S., and the fact that use of this propulsion technology reduces demand for and thus preserves the supply of plutonium needed for very deep space missions,” said Glen Hiemstra of Futurist.com. “Obviously, a key challenge in space exploration and development is the provision of adequate energy for propulsion — or in the case of human missions, life support.”
Competing technologies, such as solar arrays, may meet some of those needs in near-to-Earth missions, but would be inadequate beyond Mars and certainly not adaptable for deep space exploration, as the Los Alamos study notes.
“Thus the need for an energy source that is long-lasting, not terribly heavy, and reliable,” Hiemstra told TechNewsWorld. “The uranium plus heat pipe plus Stirling engine system seems to fit all of those needs. As proposed, it would be confined to use on small science exploration craft.”
It could be scaled up to provide a power source for long-term colonies as well — on the moon, on Mars, or even for mining of asteroids.
“Elon Musk has recently advocated a program that would eventually send 80,000 people a year to Mars, up to a total colony size of a million people,” added Hiemstra. “Nuclear energy sources such as the one proposed would make such dreams more feasible.”
Fears Over Nuclear
The biggest hurdle that future space explorers may have to overcome might not be enduring the limitations of space travel but just getting nuclear-powered space vehicles to be accepted. Nuclear tends to have a negative connotation with many people, which leaves some projects grounded.
Are these fears justified? After all, it is a nuclear reactor on a rocket.
“Space nuclear technology, in general, is very well developed and includes radioisotope thermoelectric generators and nuclear reactors as power sources,” said Gruntman. “The former is flying on distant space missions, while the latter — nuclear reactors — are sitting on shelves and could not fly for reasons other than maturity, efficiency or safety. Not only general public, but also engineering education exhibits major deficiencies in understanding nuclear aspects of technology.”
“Even launches of RTG-powered spacecraft cause protests by the anti-everything-nuclear crowd,” he added. “Public attitude toward — or should I say against — nuclear technology is based on ignorance and media-pumped emotions which have nothing to do with reality.”
Without the risk, there will be no reward.
“If we want solar system exploration, we must utilize nuclear technology,” Gruntman stressed.
The irony is that without the risk there could be even greater risk. Earth could be unprepared in the event a science fiction thriller-worthy scenario should unfold.
“In addition, if one day we will need to defend the planet Earth against a civilization-ending incoming comet or asteroid, it will require nuclear technology,” he added. “So, the human race may pay a major price for self-inflicted ignorance.”
Well Nuclear could power rockets using electrical systems that emit Ions which would be a more powerful Ion drive system with much more thrust than current Ion drive systems. The problem would be largely how to shield the rest of the ship from radiation from space and from the power supply and a need for a very large startship that can sustain its life support using its own home grown food system that can also generate home grown atmosphere from the plants providing food. An Eco system wherby waist is somehow recycled into soil and a system of creating usable water to preserve the whole eco system is the larger of the issues. How to you tell the people who are travelling that the system will recycle thier shower water and toilet water to be used as drinking water again. Not a popular thought but one that can currently be done and is being done on many newer Cruise Ships. You would basically need a space city built with many automated robotic processes related to it. Developement of many technologies needs to be pursued including ROBOTS or androids that can perform cleaning and tasks without consuming the food needed to sustain the scientists, doctors and astronauts on board. An advanced medical setup to preserve life onboard. All this is an additional power drain that needs to be considered as well in the production of Nuclear power for operate the ship. Then redundancies.. What do you do in the case of an accident or meltdown… Eject the Core of course. Now what?? you need a secondary system you can bring online in short order that is as efficient as the first. Solar at times can help but in deep space woudl be useless, What about collection system that can collect the abundant hydrogen and gasses in the dead of space and convert that to energy an a propulsion system. A ship would need to be developed with redundancy, several propulsion solutions that are not relied on each other so that a disaster can be averted and damages can be repared. Nano tech batteries that use nanotubes to store massive AM ounts of energy logn term. I future variant of the LifePo4 battery than will not explode or catch fire or overload. All systems would need redundancy so many technologie options need to be developed and put into service. The reality of this type of space travel is billions or trillions in research dollars and many years from materialization. Due to the lack of a centralized motivation and funding this may never happen. It will take unfortunately a close call where humanity realizes all our eggs are in this one basket before governments stop bickering and warring and start putting thier rescources into something truely constructive like galactic expansion and learning to live in environments withouth negatively affecting them. Imagine the possibilities if we achieved this and the knowledge we would attain of how the universe truely works… The worlds we could see and discover and the beauty we could envision in these truely spectacular sites. Ability to get rescources from asteroids or other planets would be needed as the materials to build such large ships would be emmense and would obiously affect the mass of earth as we built more million tonne ships to send out to space. Advanced in Metals and materials that are resilient and strong. Advances in powered shielding that can inherintly deflect or redirect particles in space away from or around the hull of the ship as at high speeds a small partical of dust traveling very fast could destroy the ship. Ability to control gravity on board and prevent inertia as well so that people on board do not get jarred around by sudden course corrections. Possibly use gravity as a propellant with the masses of the celestial bodies acting on the ship. The need for defenses against the unknown. Spend all these trillions just to be blown to smithers by an alien that doesnt want mankind in outer space. Great speed will be needed to cross great distances even to our closes neighboring Solar system in Aphla Centari. Too many variables in this that need to be advanced significantly and mankind is too preoccupied with personal greeds and pettiness in ideology instead of acceptance that not all people believe or feel the same thing. I would be happy to see mankind achieve something so great. But it is unlikely to happen.
What a bizarre article. It describes a new or alternative way to generate electricity in space. So? How does that Blast Humans into Deep Space? How do you translate all the electricity generated by DUFF into propulsion? You don’t give even a hint of how all this electricity will make a manned spacecraft accelerate into "deep space." And what is this Blasting"? DUFF doesn’t seem to involve blasting.
Science writing is so pathetic these days. Amateur science writing, that is.
At the conclusion of a very captivating article the writer chooses to take a defensive stance against potential nuclear technology protestors. He presumes that the non-nuclear advanced citizen, ignorant and living unrealistically in a media pumped environment should, for our own good take the risk (biting the multi-billion dollar financial bullet) so the scientific community can save us from an unknown, but scary as hell attack from outer space. And if we don’t, the writer implies that we may be responsible for our own "self-inflicted ignorance."
"Without the risk, there will be no reward." What reward, pray tell? The cash goes from our pockets to your pockets with no insurance that it might be misspent. Perhaps the writer is a might ignorant that we are living in the nuclear age, a might suicidal since 1945. Only a few nuclear meltdowns have happened since then, the most recent being Fukushima. No sweat, its them, not us. My Masters degree is in science, so we’re brothers in the quest for unlimited knowledge. The only difference between thee and me is that thee is willing to take the risk of irradiating me and the human race to reach your goal, while I refrain from such ignorant, barbaric behavior.