If you've put off scheduling a Mars trip due to the threat from solar particle events and other sources of radiation a portable magnetosphere might some day make a trip to Mars much safer.
The solar energetic particles, although just part of the 'cosmic rays' spectrum, are of greatest concern because they are the most likely to cause deadly radiation damage to the astronauts.
Large numbers of these energetic particles occur intermittently as "storms" with little warning and are already known to pose the greatest threat to man. Nature helps protect the Earth by having a giant "magnetic bubble" around the planet called the magnetosphere.
....Researchers at the Science and Technology Facilities Council's Rutherford Appleton Laboratory, the Universities of York, Strathclyde and IST Lisbon, have undertaken experiments, using know-how from 50 years of research into nuclear fusion, to show that it is possible for astronauts to shield their spacecrafts with a portable magnetosphere - scattering the highly charged, ionised particles of the solar wind and flares away from their space craft.
Computer simulations done by a team in Lisbon with scientists at Rutherford Appleton last year showed that theoretically a very much smaller "magnetic bubble" of only several hundred meters across would be enough to protect a spacecraft.
Now this has been confirmed in the laboratory in the UK using apparatus originally built to work on fusion. By recreating in miniature a tiny piece of the Solar Wind, scientists working in the laboratory were able to confirm that a small "hole" in the Solar Wind is all that would be needed to keep the astronauts safe on their journey to our nearest neighbours.
Dr. Ruth Bamford, one of the lead researchers at the Rutherford Appleton Laboratory, said, "These initial experiments have shown promise and that it may be possible to shield astronauts from deadly space weather".
Energetic protons are mainly produced during solar particle events, sporadic showers that usually coincide with maximum sunspot activity. More dangerous is galactic cosmic radiation (GCR), atomic nuclei produced during supernova explosions that travel at almost the speed of light. GCR arrives from all directions, and induces cancer as it hurtles through the body. On Earth, the planet's magnetic field and atmosphere combine to deter and block these particles. But shielding a spacecraft requires mass, and the mass of shielding that can practically be launched on a spaceship will only reduce GCR by 20% to 30%, says Frank Cucinotta, of NASA's Space Radiation Health Project at the Johnson Space Center.
We need better robot tech in order to colonize Mars. The robots could go first and do lots of work to create living quarters and enclosed farms before humans arrived. We also need better photovoltaics or workable fusion reactors for energy. Plus, we need lots of genetic engineering to create organisms to provide a variety of products for colonists. Most of this tech will get developed for other reasons. So colonization of Mars will become much easier with time.
|Share |||Randall Parker, 2008 November 04 09:34 PM Space Exploration|