British scientists are developing a force-field to protect astronauts and spacecraft from hazards on future missions to the moon, Mars and beyond. Although the shield is unlikely to withstand a full-on assault from the Klingons, it is designed to act as a ‘virtual umbrella†to shelter astronauts and sensitive electronics from the violent blasts of radiation that erupt from the sun.
Different versions of the shield are envisaged for spacecraft embarking on lengthy interplanetary journeys and for pioneering colonies of astronauts taking the first steps to building an extraterrestrial outpost.
High levels of radiation make space an extremely dangerous place. Energetic charged particles whipped up by exploding stars in distant galaxies are flung towards our solar system at close to the speed of light. These are accompanied by bursts of solar radiation unleashed by powerful shockwaves on the sun.
Combined, they can tear through electronics and short-circuit computers. They can also pass through flesh and split DNA, causing mutations that steadily increase the risk of cancer.
On Earth we are shielded from the worst excesses of cosmic and solar radiation by the planet’s magnetic field, which deflects the particles as they arrive.
Researchers at the Rutherford Appleton Laboratory in southern England hope to mimic the effect that protects Earth by making their own radiation shield, using superconducting magnets to create a powerful magnetic field that can cloak an astronaut or an entire spacecraft.
Such a force field could be invaluable for Nasa’s proposed missions, which will see astronauts set up a moonbase that they will ultimately use as a stepping stone for a manned mission to mars.
Researchers are investigating whether they can further strengthen the shield by filling the magnetic field with plasma — a cloud of ionised particles. They believe that radiation penetrating the plasma will generate waves that, in turn, create strong electric fields which will help slow the speeding particles.
‘If we pursue plans for a moonbase, this would work like a virtual umbrella for people who are going to have to work outside,†said Mike Hapgood, a scientist on the team. Because the moon has no magnetic field, the radiation levels are much higher than on Earth.
The greatest radiation threat to astronauts comes from the unpredictable outbursts from the sun. Alert services run by Nasa, the US space agency, can give only a few minutes’ warning of an imminent radiation blast.
‘If we want to explore the solar system properly, we are probably going to need a forcefield like this,†said Hapgood. ‘With current technology you can get to Mars and back, but to spend longer in space the radiation hazard is going to be much greater.â€
The shield is also expected to help unmanned space missions. Radiation can destroy electronic circuitry and corrupt software, sometimes putting missions at risk. —