"Solar (or star) flares of protons, and occasional and severe hazard on the way out of and into planetary systems, can give doses of hundreds to thousands of rem over a few hours at the distance of the earth. Such doses are fatal and millions of times greater than the permitted dose. Death is likely after 500 rem in any short time."
"Cosmic particles are dangerous, come from all sides, and require at least two meters of solid shielding all around living organisms. Earth's atmosphere provides the equivalent of 10 meters of shielding."
"By comparison, solar flares can deliver GeV protons in the same energy range as most cosmic particles. Increase of energy accounts for most of the increased radiation danger, because GeV protons or their products will penetrate several meters of material." - John Mauldin, p226 Prospects For Interstellar Travel
Read it and weep!
"Cosmic particles are dangerous, come from all sides, and require at least two meters of solid shielding all around living organisms. Earth's atmosphere provides the equivalent of 10 meters of shielding."
"By comparison, solar flares can deliver GeV protons in the same energy range as most cosmic particles. Increase of energy accounts for most of the increased radiation danger, because GeV protons or their products will penetrate several meters of material." - John Mauldin, p226 Prospects For Interstellar Travel
Read it and weep!
The emphasis is mine. They "can" give those doses but nowhere does it say they always will especially as mentioned before because they are directional (not all are pointed our way) and they vary in intensity. And as for cosmic rays, your own source says the Earth is shielded from them by the atmosphere. All spacecraft orbit above the atmosphere. All spacecraft are therefore vulnerable to cosmic rays. They are not a great danger because of their infrequency and because as mentioned they often pass through things without effect. If considering interstellar travel however, they are more of a cause for concern because of the cumulative effect from the years of travel. Take your head out of the sand and learn something.

