Positron Dynamics has seed funding from Paypal billionaire Peter Thiel’s Breakout Labs. Initial simulations show that as much as 10 micrograms of positrons could be produced each week with a linear accelerator,” says co-founder Ryan Weed, PhD, a physicist and former cryogenic engineer for Jeff Bezos’s space flight company Blue Origin. We could see the beginning of the age of commercial antimatter within five years.
There have been other space based antimatter production concepts, which could scale to a gram of antimatter per year using about 11 GWe of power. This would be about 2000 times the production of what Positron Dynamics would try to produce from one linear accelerator (520 micrograms per year)
Also storage of antimatter in the vacuum of space could be easier. Storage and handling of significant amounts of antimatter are a greater unknown than the larger scale production of antimatter.
Proposed orbital antimatter storage using superconducting rings
A Plasma Magnet concept for capturing antimatter trapped in planetary magnet fields consists of a relatively small (10-100 meter) four-loop antenna situated within a neutral plasma. By supplying current to opposing loops with a relative phase difference, a rotating magnetic field (RMF) is established near the antenna. The RMF is operated at a sufficiently high frequency so as to elicit a response in the electron population, while the motion of the proton population (due to their relatively high mass) may be ignored. The resulting current due to the electron motion sustains a large-scale magnetic field within the plasma. The principle driver of performance is the RMF antenna’s ability to influence the electron population; the more electrons driven by the RMF, the stronger the resultant magnetic field. We can quantify this by establishing a magnetization criterion, and determining a penetration depth for the RMF that will depend on (i) the antenna coil radius; (ii) the antenna operating current; and (iii) the temperature of the bulk plasma.
Overall antiproton collection rates exceed micrograms per year for typical systems that are just 100m in size while drawing just a few hundred kilowatts of power. This implies that the complete device could be inserted into its operational orbit with a single launch.
Though the plasma magnet significantly reduces the need for high current wires, RF coils would still benefit from higher current densities. High temperature superconductors with current densities much greater than 10^10 A/m2 at 90K will enable far more compact and mass-efficient systems.
Nuclear fusion or any larger power source that can be put into space combined with superconductors will enable antimatter production that can be 100,000 to one million times more efficient in terms of cost than earth based systems.
* A $50-100 million system with 200 KW of power using current (or conservatively within four year technology) could produce several micrograms of antimatter each year.
*A one gigawatt power system inside of an earth orbiting superconducting traps could produce 95 milligrams of antimatter per year. Antimatter could be used to enable super high performance space ships.
The baseline concept calls for using conventional high temperature superconductors to form two pairs of RF coils that have a radius of 100 m and weigh just 7000 kg combined. A 5000 kg nuclear or solar power system provides the 200 kW required to operate systems and compensate for dissipative losses in the plasma. The magnetic field induced by plasma motion driven by the RF coils is used to first concentrate the incoming antiprotons and then to trap them. Based on the Earth antiproton flux, the system would be capable of collecting 25 nanograms per day and storing up to 110 nanograms of it in the central region between the coils. The system is more than five orders of magnitude more cost effective than Earth based antiproton sources for space-based applications.
The system could collect antimatter at the rate of 8.6 micrograms per year. It only stores 110 nanograms so the stored antimatter would need to be shifted every few days to more permanent storage.
Technology Development Requirements
The collection and use of antimatter produced naturally in the space environment requires four fundamental advances: an understanding of the natural distribution of antimatter, a highly efficient collector, a stable storage medium, and a mechanism to induce thrust. The proposed collection system does not require the development of any fundamentally new technology to make it work.
However, the demonstration of key technologies and significant improvements in several areas would improve the risk weighted economic feasibility. To this end, we have identified the following technologies that need to be demonstrated at a TRL level of seven (7) or above.
Technologies in order of importance
• Compact mass spectrometer placed in highly eccentric orbit. In situ measurements of antimatter fluxes in the Earth’s radiation belt and around the Jovian planets have not been made. The models developed as part of this program should be verified by direct experimental evidence before significant resources are committed to implementing a full system. Current orbital missions do not have the spatial and/or property coverage to characterize the relevant environment. A compact mass spectrometer capable of differentiating protons, antiprotons, electrons, and positrons should be developed and flown in a highly eccentric orbit with an apogee of at least six Earth radii (6 RE) to completely characterize the antiproton and positron environment. Such a system will also contribute greatly to radiation belt knowledge and the interaction between the magnetosphere and the Sun.
• Large-scale demonstration of a plasma magnet. The technology is a critical path item that appears to provide the only mass-efficient system capable of collecting significant quantities of antiprotons. The RF generation equipment and its integration with large-scale coils in the space environment need to be demonstrated.
• Low mass, high strength, long strand, ultra-high current loops. Though the plasma magnet significantly reduces the need for high current wires, RF coils would still benefit from higher current densities. High temperature superconductors with current densities much greater than 10^10 A/m2 at 90K will enable far more compact and mass-efficient systems.
• Radiation tolerant in-orbit power source. The particle collection system is required to operate in a high radiation environment. Though the magnetic field will shield the system from much of the incoming flux, a radiation tolerant power source is necessary to generate the initial current before the field is fully established. The intrinsic energy contained in the field dictates that a high power source be available in order to charge the system in a reasonable time. A space-qualified nuclear reactor with a power output of at least 100 kWe is desirable.
• Antiproton catalyzed fission/fusion engine. Nanograms to micrograms of antiprotons do not have enough intrinsic energy to propel a spacecraft to high velocities when exclusively using the annihilation products. Instead, most concepts rely on using antiprotons to induce fission reactions. The antiprotons catalyze nuclear reactions in sub-critical fissile material to propel the vehicle by leveraging the nuclear material in a safe and controllable manner.
• Passive cooling systems. Reduced-mass multi-layer thermal blankets for passive temperature control of large structures with Tmax < 90K at 1 AU will improve the overall mass efficiency and reduce requirements on the high temperature superconductors wires used. • Affordable lift. Reducing the cost to orbit with new affordable heavy lift options, though not strictly required, will improve overall feasibility.
The ‘base design’ consisted of a 4000 ton model planned for ground launch from Jackass Flats, Nevada. Each 0.15 kt of TNT (600 MJ) (sea-level yield) blast would add 30 mph (50 km/h, 13 m/s) to the craft’s velocity. A graphite based oil would be sprayed on the pusher plate before each explosion to prevent ablation of the surface. To reach low Earth orbit (300 mi), this sequence would have to be repeated about 800 times, like an atomic pogo stick.
Most of the three tons of each of the “super” Orion’s propulsion units would be inert material such as polyethylene, or boron salts, used to transmit the force of the propulsion unit’s detonation to the Orion’s pusher plate, and absorb neutrons to minimize fallout.
Very Low Fallout Antihydrogen Bombs for Revamped Project Orion
One microgram of antihydrogen would be theoretically by enough to be the trigger for one kiloton antihydrogen bombs. By not having a nuclear fission trigger the amount of fallout is massively reduced. These would be about the size needed for pulse units for project orion style nuclear pulsed propulsion. Each one of the plasma magnet antimatter traps would be able to produce the antimatter for about 8 antihydrogen bombs per year.
On March 24, 2004, Eglin Air Force Base Munitions Directorate official Kenneth Edwards spoke at the NASA Institute for Advanced Concepts. During the speech, Edwards ostensibly emphasized a potential property of positron weaponry, a type of antimatter weaponry: Unlike thermonuclear weaponry, positron weaponry would leave behind “no nuclear residue”, such as the nuclear fallout generated by the nuclear fission reactions which power nuclear weapons.
Other Possible Antimatter Weapons
The most important application is fallout free pulse units for project orion to launch without fallout. Launch costs would drop to $1-5/kg. Plus interplanetary and even interstellar propulsion would be enabled.
In addition to the advantages related to its extremely high energy density and ease of ignition, annihilation has two important characteristics: the release of energy in a matterantimatter explosion is extremely fast (ten to a thousand times shorter than a nuclear explosion), and most of the energy is emitted in the form of very energetic light charged particles (the energy to mass ratio of the pions emitted in annihilation is two thousand times higher than the corresponding ratio for the fission or fusion reaction products). With the help of magnetic fields, very intense pion beams can be created, of the order of 100 megaamperes per microgram of antiprotons. Such beams, if directed along the axis of an adequate device, can drive a magnetohydrodynamic generator, generate a beam of electromagnetic waves, trigger a cylindrical thermonuclear explosion, or pump a powerful Xray laser. In the last case, for example, the pions’s energy could be used to transform in a very uniform plasma, a long cylinder of a substance such as selenium, whose ionized atoms have excited states favorable to the spontaneous emission and amplification of coherent Xrays. But this is only one of the many concepts that permit, thanks to antimatter, to conceive Xray lasers having efficiencies ten to a thousand times higher than those pumped by any other known energy sources.