October 21 has been thrown around a bit
Have a look at this chart at the the top of the page and fast forward to October 21.. A huge comet flying right in front of the earths path and then the Earth going through the tail shortly after may be interesting to say the least..
http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=elenin;orb=1;cov=1;log=0;cad=1#cad
