Deflector shields, similar to those seen in Star Trek and other science fiction stories, may soon be a reality. In the short term, they may even be used to protect space travelers on the way to Mars.
Rutherford Appleton Laboratory (RAL) researchers are developing a lightweight system which could be used during trips to the Red Planet and beyond. The researchers have built a scale spacecraft which they have successfully protected from radiation.
Cosmic rays and other sub-atomic particles form the Sun could pose a real danger to astronauts on long journeys outside the relative safety of our planet's protective magnetic field. Without adequate shielding, a trip to Mars could prove to be potentially hazardous, or even fatal.
The idea behind the design revolves around the creation of a magnetic field around spacecraft that would deflect charged particles the same way as the Earth's magnetic field. This is known as a mini-magnetosphere.
"[A] constant electric field... can be enough that it actually refracts or deflects enough of the radiation from inside the magnetic cavity that you've formed to protect the astronauts... enough like the Earth that they can survive," Ruth Bamford, lead researcher for the deflector shield project at RAL, said.
Like on the Earth, this miniature magnetic field, although not perfect, would provide a first line of defense against incoming radiation.
The Sun emits a steady stream of charged particles into the solar system. Flares and coronal mass ejections can greatly increase the number of potentially harmful subatomic particles which could collide with a ship from the Earth. There are also galactic cosmic rays (GCR) to worry about as well. During the Apollo project, astronauts on their journey to the Moon received almost 1,100 times as much cosmic radiation as people who stayed on Earth.
The next step in development will be the design of a concept spacecraft called Discovery, which will have a full-scale mini-magnetosphere.
The advantage of a deflector shield is that the equipment needed to create the field weighs less than protecting the craft with metal shielding. Inspiration Mars, a private project which intends to launch humans to Mars in 2018, will use a much lower-tech approach. They will shield their craft with the water and food needed for the journey, along with the inevitable human excrement which will result.
"Star Trek has great ideas - they just don't have to build it," Bamford said.
