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Solar Flares Shield Astronauts from Cosmic Rays
It doesn't come easy writes "Considering all of the research into better shielding for astronauts, it's interesting to note that solar flares can help shield space travelers from dangerous cosmic rays. From the article: "The crew of the ISS absorbed about 30% fewer cosmic rays than usual [during this last month of high solar activity]," says Frank Cucinotta, NASA's chief radiation health officer at the Johnson Space Center. "The storms actually improved the radiation environment inside the station." Scientists have long known about this phenomenon. It's called a "Forbush decrease," after American physicist Scott E. Forbush, who studied cosmic rays in the 1930s and 40s. So, I guess it would be safer to plan a manned Mars mission to coincide with peak sunspot activity?"
So, I guess it would be safer to plan a manned Mars mission to coincide with peak sunspot activity?"
How about having the spacecraft generate its own external magnetic field? How effective would that be?
Apparently, the Earth magnetic field has decreased by 10% in the last 10 years. I'm an electrical engineer and during my studies in sub-atomic physics, I learned that a particles velocity can be effected by magnetic fields. I keep hearing about the increased activity of our Sun and I believe it's possible that more of the Sun's radiation is penetrating the Earth's magnetic field due to it being weaker. If more radiation hits the Earth and the Sun is spewing out more heat, shouldn't that also increase the overall temperature of the Earth and can global warming be attributed to this? I've been bouncing this idea in my head for a while now and I can't see why this MAY not be true.
True, sadly, Slashdot is reposting yubanet's repost of NASA's story of last week. Even worse, Slashdot will repost this story within 24 hours.
The reason for this decrease in galactic cosmic rays is that the solar flares and coronal mass ejections themselves emit relativistic electrons and solar cosmic rays (mostly protons) which are responsible for pushing the galactic particles back. The number of solar energetic particles emitted during flares is much larger than the galactic source. In addition to the energetic particles, the sun also emits copious amount of hard and soft X-rays during solar flares.
I don't think that it matters much to an astronaut whether the ionizing radiation is galactic or solar in origin. As for solar flares improving the radiation environment inside the space station, I find that statement very curious. With experts such as this, maybe that's why they announced the closing of the Space Environment Effects division at NASA last week.
Fields stronger than 100,000 Gauss can levitate living things.
I've stuck the movie of the levitating frog up here
An excellent point, and one that probably will mean that it is, in fact, safer to try and avoid spaceflight during high solar activity (when possible). On the other hand, the danger is only there if the CME is directed in your general vicinity. Sure, the Earth gets hit with a solar flare (or its remnants, actually) from time to time, but it does not get hit with every solar flare the Sun produces.
High-energy protons from CMEs are bad things too. I'm not sure avoiding low-energy cosmic rays is sufficient. A flare can knock out satellites via accumulated charge buildup.
Relativistic effects also alter the apparent half-life of free neutrons. Neutrons traveling at relativistic speeds will have significantly longer lives relative to us. Particle accelerators rely on this effect to work with short-lived particles.