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parallaxicality
2007-Feb-03, 09:45 AM
I've heard that the solar system's bow shock can be a source for cosmic rays, but I can't verify it. Is it true?

Ithildin
2007-Feb-03, 10:28 AM
There doesn't seem to be any particular reason that the bow shock could be a significant source of cosmic rays that hit the Earth; actually, the bow shock does a great job of shielding the solar system from alot of the incoming rays as the sun travels through space.
Various particle collisions could probably result in the bow shock area, but it seems doubtful that most of the cosmic rays created there would reach and be detected on Earth.
I hope that helps? :)

astromark
2007-Feb-03, 10:32 AM
Please define 'cosmic rays'
Other than that I do not see why there is any surprise that a measurable shock wave is present as a bow wave in the direction of movement of the solar system. After all the sun is out poring a great deal of energy. It seems perfectly logical that it is able to be measured as a source of fluctuation to the radio telescopes signal strength. I always thought cosmic rays were just the measured energy output of a star. Please put me straight.?

Ithildin
2007-Feb-03, 10:47 AM
"Cosmic ray" is actually just a broad name for any high energy particles not originating on Earth. A good deal of what we can detect are Protons and also a significant amount of alpha particles (Helium nuclei).
Most cosmic rays, as far as we currently know, results from supernova explosions, along with active galactic nuclei and the like.

astromark
2007-Feb-03, 10:57 AM
Thanks Ithildin.

satori
2007-Feb-03, 02:19 PM
Magicblue Ithildin,
could you please expand on the notion that we are sreened from harm by the solar bow shock..

Ithildin
2007-Feb-04, 05:17 AM
Well, it's not so much from the bow shock itself, but more because of what is causing the bow shock. At the solar bow shock region, solar wind from the sun is hitting interstellar particles; water gathering on the bow of a ship is a good analogy.
So, rather than interstellar particles hitting the Earth, they hit against solar wind which blocks them from entering the solar system and thus 'shields' the solar system to an extent. The Wikipedia article on bow shock has a nice illustration of the effect:
http://en.wikipedia.org/wiki/Bow_shock
I’m more of a visual person myself :)