Brian Skiff wrote: > In the style of the Messier Marathon, I wonder what is the optimum > season to observe the Herschel 400, and whether you could get the bulk of > them (say 300+) in a single night. I've got the H400 entered into an Excel file. Sorting the data by right ascension produces the following breakdown: ..RA......# Objects 00-02...........34 02-04...........15 04-06...........19 06-08...........41 08-10...........27 10-12...........65 12-14...........97 14-16...........17 16-18...........22 18-20...........28 20-22...........19 22-00...........16 The cluster around 12 go 14 hours RA includes all those Virgo galaxies. If you include the objects at 10 to 12 hours RA (lots of galaxies, again), that makes for 162 total objects, which would be a good night's work by any standard. The Messier marathon is targeted for late March because the Sun resides within that convenient void between 21:40 RA and 00:40 RA where only M52, a circumpolar object in the Northern Hemisphere, resides. Only about 25 Herschel 400 objects reside within that gap. Theoretically, it is possible to get all but 25 of the H400 while everybody else is working at the Messier objects. Bill Ferris "Cosmic Voyage: The Online Resource for Amateur Astronomers" URL: http://www.cosmic-voyage.net -- See message header for info on list archives or unsubscribing, and please send personal replies to the author, not the list.