Cosmic rays have enough energy to travel through the atmosphere and damage the sight of commercial pilots. Its not a leap to think that the exposure is significantly higher in orbit.<p><a href="http:&#x2F;&#x2F;news.bbc.co.uk&#x2F;2&#x2F;hi&#x2F;health&#x2F;4131232.stm" rel="nofollow">http:&#x2F;&#x2F;news.bbc.co.uk&#x2F;2&#x2F;hi&#x2F;health&#x2F;4131232.stm</a><p><a href="http:&#x2F;&#x2F;www.ncbi.nlm.nih.gov&#x2F;pubmed&#x2F;16087845" rel="nofollow">http:&#x2F;&#x2F;www.ncbi.nlm.nih.gov&#x2F;pubmed&#x2F;16087845</a>