Swarm of laser-sail spacecraft leaving the solar system. Credit: Adrian Mann
Between the exponential growth of the commercial space industry (aka. NewSpace) and missions planned for the Moon in this decade, it’s generally agreed that we are living in the “Space Age 2.0.” Even more ambitious are the proposals to send crewed missions to Mars in the next decade, which would see astronauts traveling beyond the Earth-Moon system for the first time. The challenge this represents has inspired many innovative new ideas for spacecraft, life-support systems, and propulsion.
In particular, missions planners and engineers are investigating Directed Energy (DE) propulsion, where laser arrays are used to accelerate light sails to relativistic speeds (a fraction of the speed of light). In a recent study, a team from UCLA explained how a fleet of tiny probes with light sails could be used to explore the Solar System. These probes would rely on a low-power laser array, thereby being more cost-effective than similar concepts but would be much faster than conventional rockets.
Illustration of the concept using light signals rather than radio. Credit: Yen Strandqvist/Chalmers University of Technology
If humans want to travel about the solar system, they’ll need to be able to communicate. As we look forward to crewed missions to the Moon and Mars, communication technology will pose a challenge we haven’t faced since the 1970s.
If we ever colonize Mars, nature will have to accompany us. Artist's concept of a habitat for a Mars colony. Credit: NASA
So you want to colonize Mars, huh? Well Mars is a long ways away, and in order for a colony to function that far from Earthly support, things have to be thought out very carefully. Including how many people are needed to make it work.
A new study pegs the minimum number of settlers at 110.
While many visionaries now focus upon Mars as the next destination for humankind to visit, some have an even longer view. In the book, “Interplanetary Outpost: The Human and Technological Challenges of Exploring the Outer Planets,” you can take a ride with the author Erik Seedhouse to possibly the next most habitable body in our solar system. You can visit Callisto in the Jovian system. However, on reading this book you will quickly discover that it won’t be a simple journey there and back again.
Imagine yourself wanting to get involved with that first trip to Callisto. What would you do? Where would you begin? Well, this book could be a really good high level overview for the requirements for your endeavour.
First, it reminds you on why Callisto is the best target. Here it draws upon earlier NASA efforts, including RASC-Revolutionary Aerospace Systems Concepts and HOPE-Human Outer Planet Exploration. It also continually references recent movies like Avatar and Pandorum as supporting work. With the references aside, the book settles down and focuses you upon its prime directive, a one-off exploration endeavor, even smaller than the multiple missions of Apollo to the Moon. Therefore, much of the book’s information serves to satisfy this one-off.
As you read, you will discover more and more requirements and pre-conditions. For example, according to this book, you will be departing from a spaceport parked in CIS-Lunar orbit. You will travel on the optimal path to arrive at Callisto without hitting Jupiter or being affected by its radiation fields. You will use electrical onboard power from a nuclear generation system. Your craft will be powered by a variable specific impulse magnetoplasma rocket. Your body will be suspended cryogenically on the flight. Your body will be filled with nano-biomechanical devices so that you are in functional shape when you arrive. An onboard computer (not named HAL) will sustain both your sleeping body and the spacecraft on its multiyear journey. And so the book’s list of pre-conditions continues on. Thus, as you can well imagine, the book takes you along a path that perhaps is more akin to science fiction than science fact even though it argues that the technologies are all nearly-here! Topping this list is the submersible that launches you into the ice-covered oceans of Callisto. In any case, humankind will have to do a huge amount of prior development before you ever get to this Jovian moon; at least according to this book.
The book’s reliance upon un-proven or even non-existent technology is what will likely either make or break it for you. In effect, the book reads as if the author accumulated a large number of scientific research papers and turned them into a comprehensive, very entertaining prose for the general audience. If you want to be entertained, then this book is for you. If you want to get into a bit more of the nitty gritty, well then you may be less entertained. For example, the book has an expectation that explorers on Callisto will utilize GPS receivers to help them navigate. But, there is no mention of a GPS satellite constellation orbiting Callisto. And what about cryogenics? While the book does mentions some ongoing research today, we certainly don’t consider it mainstream. You may learn of new words like ‘respirocytes’. This knowledge could serve you well at cocktail parties but may not get you much headway at the next meeting of the local astronomical society. So, this reliance upon un-proven or non-existent technology should be kept in mind before you read this book.
However, at one time, some people were imaginative enough, or brave enough, to envision humankind doing more than staying upon planet Earth. Sure the Moon is close and Mars is apparently only slightly further. But there’s a whole universe out there just waiting for us. Are you sure what might be the best path for our species? Take a read of Erik Seedhouse’s book “Interplanetary Outpost – The Human and Technological Challenges of Exploring the Outer Planets”. It might change your perspective as it takes you on a ride the likes of which will never have been seen on Earth before.
The Farnsworth Fusor; Pons and Fleishmann. It seems the trail to fusion energy has long gone cold — stone cold, that is, and not cold as in cold fusion. Despite the promise of fusion providing a sustainable and safe energy source, fusion reactors are not a dime a dozen and they won’t be replacing coal fired power plants any time soon. Or will they? Lockheed-Martin Skunk Works announced a prototype compact fusion reactor that could be ready within five years. This revelation has raised eyebrows and sparked moments of enthusiasm.
But, let’s considers this story and where it all fits in both the history and future.
For every Skunk Works project that has made the runway such as the Stealth Fighter or SR-71 Blackbird, there are untold others that never see the light of day. This adds to the surprise and mystery of Lockheed-Martin’s willingness to release images and a detailed narrative describing a compact fusion reactor project. The impact that such a device would have on humanity can be imagined … and at the same time one imagines how much is unimaginable.
Lockheed-Martin engineers in the Skunkworks prepare a vessel, one component of an apparatus that they announced will lead to nuclear fusion in a truck-sized reactor within 5 years. An international effort is underway in Europe to create the world’s first practical tokamak fusion reactor, a much larger and costlier design that has never achieved the long sought “breakeven” point. (Photo Credit: Lockheed-Martin)
The program manager of the Skunk Works’ compact fusion reactor experiment is Tom Maguire. Maguire and his team places emphasis on the turn-around time for modifying and testing the compact fusion device. With the confidence they are expressing in their design and the ability to quickly build, test and modify, they are claiming only five years will be needed to reach a prototype.
What exactly the prototype represents was left unexplained, however. Maguire continues by saying that in 10 years, the device will be seen in military applications and in 20 years it will be delivered to the world as a replacement for the dirty energy sources that are in use today. Military apps at 10 years means that the device will be too expensive initially for civilian operations but such military use would improve performance and lower costs which could lead to the 20 year milestone moment if all goes as planned.
Their system uses magnetic confinement, the same basic principle behind the tokamak toroidal plasma confinement system that has received the greatest attention and government funding for over 50 years.
The ITER Tokamak Fusion Reactor is expected to begin operational testing in 2020 and begin producing deuterium-tritium fusion reactions in 2027. (Credits: ITER, Illus. T.Reyes)
The International Thermonuclear Experimental Reactor (ITER) is currently under construction in Europe under the assumption that it will be the first net energy producing fusion generator ever. It is funded by the European Union, India, Japan, People’s Republic of China, Russia, South Korea and the United States. But there are cost over-runs and its price has gone from $5 billion to $50 billion.
ITER is scheduled to begin initial testing in 2019 about the time Lockheed-Martin’s compact fusion reactor prototype is expected. If Lockheed-Martin succeeds in their quest, they will effectively have skunked ITER and laid to waste a $50 billion international effort at likely 1/1000th the cost.
There are a few reasons Lockheed-Martin has gone out on a limb. Consider the potential. One ton of Uranium used in Fission reactors has as much energy as 1,500 tons of coal. But fission reactors produce radioactive waste and are a finite resource without breeder reactors, themselves a nuclear proliferation risk. Fusion produces 3 to 4 times more energy per reaction than fission. Additionally, the fuel — isotopes of hydrogen — is available from sea water — which is nearly limitless — and the byproducts are far less radioactive than with fission. Fusion generators once developed could provide our energy needs for millions of years.
More pragmatically, corporations promote their R&D. They are in a constant state of competition. They present a profile that ranges from the practical to the cutting edge to instill confidence in their Washington coffers. Furthermore, their competitors have high profile individuals and projects. A fusion project demonstrates that Lockheed-Martin is doing more than creating better mouse-traps.
To date, no nuclear fusion reactor has achieved breakeven. This is when the fusion device outputs as much energy as is input to operate it. Magnetic confinement such as the various tokamak designs, Lawrence Livermore’s laser-based inertial confinement method, and even the simple Philo Farnsworth Fusor can all claim to be generating energy from fusion reactions. They are just all spending more energy than their devices output.
An example of a homemade Fusor. Originally invented in the 1960s by the inventor of the television, Philo Farnsworth. (Credit: Wikipedia, W.Jack)
The fusor, invented in the 1960s by Farnsworth and Hirsh, is a electrostatic plasma confinement system. It uses electric fields to confine and accelerate ions through a central point at which some ions will collide with sufficient energy to fuse. Although the voltage needed is readily achieved by amateurs – about 4000 volts – not uncommon in household devices, no fusor has reached breakeven and theoretically never will. The challenge to reaching breakeven involves not just energy/temperature but also plasma densities. Replicating conditions that exist in the core of stars in a controllable way is not easy. Nevertheless, there is a robust community of “fusioneers” around the world and linked by the internet.
Mr Fusion, the compact fusion reactor that drove the 21st Century version of the DeLorean in Back to the Future. The movie trilogy grossed $1 billion at the box office. Mr Fusion could apparently function off of any water bearing material. (Credit: Universal Pictures)
It remains to be seen who, what and when a viable fusion reactor will be demonstrated. With Lockheed-Martin’s latest announcement, once again, fusion energy is “just around the corner.” But many skeptics remain who will quickly state that commercial fusion energy remains 50 years in the future. So long as Maguire’s team meets milestones with expected performance improvements, their work will go on. The potential of fusion energy remains too great to dismiss categorically.
