Page 9 Paragraph 4 in reference to the visibility of Mercury: for "around end of July" read "around the middle of July".
Update
22-12-07: Plans by the NASA Deep Impact Probe to flyby Comet Boethin in 2008 have been cancelled, as the comets orbit is not sufficiently well established. Deep Impact will instead fly-by Comet Hartley 2 in 2010. The Gamma-Ray Observatory GLAST has been re-scheduled for launch on 16th May 2008 (tentative). NASA's MESSENGER probe sucessfully flew by Mercury in January 2008, imaging and scanning the unseen side.