SUMMARY: We use the most up to date Milky Way model and solar orbit data
in order to test the hypothesis that the Sun's galactic spiral arm crossings cause
mass extinction events on Earth. To do this, we created a new model of the Milky
Way's spiral arms by combining a large quantity of data from several surveys. We
then combined this model with a recently derived solution for the solar orbit to
determine the timing of the Sun's historical passages through the Galaxy's spiral
arms. Our new model was designed with a symmetrical appearance, with the major
alteration being the addition of a spur at the far side of the Galaxy. A correlation
was found between the times at which the Sun crosses the spiral arms and six
known mass extinction events. Furthermore, we identify ve additional historical
mass extinction events that might be explained by the motion of the Sun around
our Galaxy. These ve additional signi cant drops in marine genera that we nd
include signi cant reductions in diversity at 415, 322, 300, 145 and 33 Myr ago. Our
simulations indicate that the Sun has spent
60% of its time passing through our
Galaxy's various spiral arms. Also, we brie y discuss and combine previous work
on the Galactic Habitable Zone with the new Milky Way model.
http://xxx.lanl.gov/abs/1309.4838
http://xxx.lanl.gov/list/astro-ph/new
http://xxx.lanl.gov/...1309.4838v1.pdf
If you would like a copy of these documents (because the links are dead), let me know. I am archiving important news events dating back to the turn of the century and putting them onto M-Disc.
Edited by Layberinthius, 22 September 2013 - 12:08 AM.
