An Artificial Magnetic Shield Could Protect Humans from Cosmic Radiation
An Artificial Magnetic Shield Could Protect Humans from Cosmic Radiation
An artificial magnetosphere could potentially allow transparent lunar domes, as well as consume less power than a Moon base’s vegetable garden. Because the Moon’s rotation means one side is in darkness for two weeks, the power source needs to be nuclear. Rob Coppinger, an aerospace and aviation writer, described designs exclusively for Asgardia Space News.
Lunar explorers could look up at the Earth through huge dome windows and remain safe from dangerous cosmic and solar radiation with a nuclear powered, liquid nitrogen cooled artificial magnetosphere. Without such an atmosphere, explorers and settlers would need to live in lava tubes or build surface structures with no windows and walls up to two metres thick. This would protect them from the dangerous radiation from the Sun that can come in the form of solar flares or as larger bursts of plasma known as interplanetary coronal mass ejections. Astronauts also need protection from the radiation beyond the solar system, the galactic cosmic radiation.
“You need superconductors or you need too much power. Liquid nitrogen is a good solution [for cooling the superconductor],” said Turin Polytechnic professor Carlo Caldera. Because the Moon’s rotation means one side is in darkness for two weeks, the power source needs to be nuclear and cannot be solar. Caldera pointed to NASA’s KiloPower 100-kilowatt nuclear reactor — which currently exists in prototype form — as one potential energy source. Caldera added that a Moon base could have three or four such reactors with one dedicated to the magnetic shield, despite the fact it only needs a few dozen kilowatts, less power than the base’s hydroponics garden needs. The strength of the magnetic shield, he said, would still be at a safe level.
The lunar base of linked domes would sit under the torus shaped magnetic field infrastructure.
Credit: Marco Peroni/Torino Polytechnic
The high temperature superconductor that would be used is Yttrium Barium Copper Oxide (YBCO). It is already manufactured in kilometre lengths, more than enough for the shield. The YBCO cable would be threaded through pipes full of liquid nitrogen that are half buried in the Moon’s soil and also laid across arches over the domes. The magnetic shield infrastructure is toroidal in shape, resembling a doughnut. Caldera and his researchers say that it is scalable and can be larger or smaller depending on the settlement, but they modelled a torus with a radius of 240 metres and a small radius of 45 metres.
However, an underground shelter would also be needed in case of powerful solar flare events, when the radiation would exceed the protection capabilities of the shield. The lunar base and its domes would be built using additive manufacturing, the Moon’s soil. The transparent plastic or glass envelopes for the transparent parts of the domes would need to be sent from Earth. A more open environment of this kind is expected to bring psychological benefits for the explorers.
A close up of the partial window, partial solid structure lunar base domes with the overarching magnetic field superstructure.
Credit: Marco Peroni/Torino Polytechnic
Work continues to refine the magnetic shield design and calculate how much power is needed for protection against cosmic rays. The experimental model is currently undergoing improvements for its exhibition at the International of Academy of Astronautics space exploration conference in Turin in June this year. The topic of 2019 symposium is “Moon, Mars and Beyond: Becoming an Interplanetary Civilization.”
A former engineer, Rob Coppinger has almost 20-years of experience working as a full-time staff writer and in editorial management positions in aerospace, aviation, IT and engineering publications. He had worked for the BBC, IHS, Flightglobal, Air Cargo Week, The Engineer, and many other publications. Now Mr. Coppinger is providing technical and writing expertise on a freelance basis.
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