Hello, and welcome to Beyond NERVA! Here, we look at the technology that will enable humanity to expand into the solar system, and eventually the stars.
It’s a trope in the space industry to comment after each failure that “space is hard.” The difficulties facing even now-routine space missions are seen every year, and the vast majority of these missions only go into orbit around the Earth, the first small step to going into space. As we go even further out, the challenges grow. In order to be able to have successful missions of any type, a huge number of different technologies have to come together; and often the value of the mission is limited by two key factors: reliability and power.
Reliability is an obvious concern; after all, there’s currently no chance of repairing the vast majority of systems that are launched into space (the Hubble Space Telescope being one of the only exceptions to this rule), and once a spacecraft has left Earth’s orbit there’s zero chance that repairs or maintenance can be performed.
Power is important in many different ways, and each is important. Power can mean the thrust needed to go to where you want to go, and to enter orbit or land when you get there; it can be electrical power for the experiments and other systems on board the spacecraft; finally, it can be heat to prevent the different components from literally freezing to death due to the harsh conditions found in the vast majority of the solar system. Every power system has its own advantages and limitations, but a key concept to consider in this is power density: how much power, of what kind (kinetic, electric, thermal), is available compared to the mass of the power supply that’s providing that power. Another is system robustness: how well will this system function under less than ideal circumstances, and how “less than ideal” do those circumstances have to be before it becomes a large problem, possibly ending the mission?
Nuclear power offers both reliability and power, in far greater measure than any other type of system available. From nuclear thermal rockets, which turn the heat of a nuclear reactor directly into thrust, to nuclear electric power supplies for both propulsion and the electricity that’s needed to survive in space, to nuclear pulse propulsion which uses controlled microdetonations of nuclear material to propel a spacecraft, to radioisotope generators which use the natural decay of radioactive material, nuclear power offers unique advantages in space. This is something that has been recognized, researched, and tested since the dawn of the nuclear age, but as of yet has been used in relatively few spacecraft.
Just because it hasn’t been used as much doesn’t mean that it hasn’t been researched extensively, though. Millions of man-years of effort, and billions of dollars, have been spent worldwide to research, design, and test a huge variety of concepts, and quite a number of them never flew only because there wasn’t a mission that required them.
Beyond NERVA looks into those concepts, the testing that has gone into them, and the future of nuclear power in space. With the rapid growth of the space industry over the last few decades, and the incredible leap in interest in the general public for returning to the Moon, going to Mars, and beyond, the challenges that were once considered possible but not practical in the past are now becoming much nearer to reality than they ever have been.
The fundamental challenges of spaceflight, however, have not changed. The same reasons that the early pioneers of space flight looked to nuclear power to solve the incredible challenges in front of them are leading the next generation of ambitious mission designers to once again turn to nuclear power to provide the power needed for these missions, in the mass budget that current launch vehicles – and the next generation as well – impose.
Beyond NERVA is a website with several parts. By far the most popular, and most updated, is the blog, which can be found here. Every few weeks (as often as I’m able to get the material together, often these posts involve dozens of hours of gathering sources, and dozens more reading them, before writing even begins!), we’ll look at either a particular system that has been proposed or flown in the past, a new system that is currently under development, or the fundamental technology and testing associated with bringing these systems to mission readiness. The next is topic-specific pages, exploring everything from overviews of different applications of nuclear power in space to particular types of technologies to the testing equipment and experiments needed to prepare these systems for spaceflight. Finally, at a future date we will be adding unique resources other than archival research and accessible information on historical and current designs, however that portion of the website is still in the early planning stages, and thousands of hours of work are left in compiling the information that’s already available (if not necessarily easily accessible) on the various aspects of nuclear technology for space.
Feel free to explore! Our Facebook group is fairly active, and growing every week. A new Twitter feed has also been started as well! On these, I share papers, articles, and other information relating to in-space nuclear power, and the FB group is a great place to discuss concepts for nuclear power and propulsion with a wide range of both professional and amateur enthusiasts on the subjects we cover here!