A reader sent this abstract of a Henrik Svensmark study with a
one word caption: Wow! I agree. The notion that "local" (and by
local, we mean unimaginably far away) supernova affecting the
Earth's climate is certainly creative. Haven't even read the
thing so certainly not buying it yet, but it certainly is an
amazing hypothesis. Observations of open star clusters in the
solar neighbourhood are used to calculate local supernova (SN)
rates for the past 510 Myr. Peaks in the SN rates match passages
of the Sun through periods of locally increased cluster
formation which could be caused by spiral arms of the Galaxy. A
statistical analysis indicates that the Solar system has
experienced many large short-term increases in the flux of
Galactic cosmic rays (GCR) from nearby SNe. The hypothesis that
a high GCR flux should coincide with cold conditions on the
Earth is borne out by comparing the general geological record of
climate over the past 510 Myr with the fluctuating local SN
rates. Surprisingly, a simple combinat