= Radiation Bursts =

We have been blessed, or perhaps misled, by the absence of giant geomagnetic storms or radiation bursts since the beginning of grid electrical distribution in the 1920's, and since we began orbiting satellites in the late 1950's.

=== History of storms ===
from [[ http://en.wikipedia.org/wiki/Geomagnetic_storms | Wikipedia ]]

|| 21 December 1806 || Humboldt compass observation     ||
|| 1 September 1859 || Carrington Event                 || -1750 nT est ||
|| 15 May 1921      ||                                  ||              ||
|| 13 March 1989    || Quebec grid outage               ||  -589 nT     ||
|| 14 July 2000     || Bastille Day storm               ||              ||
|| 29 October 2003  || radio blackout, satellite damage ||  -389 nT     ||


 . http://www.leif.org/research
 . http://www.scientificamerican.com/article.cfm?id=bracing-for-a-solar-superstorm
 . McCracken, K. G. et al. Solar cosmic ray events for the period 1561–1994 1.  Identification in polar ice, 1561-1950. J. Geophys. Res. 106, 21,585–21,598 (2001).