Comet 103P/Hartley 2 continues to put on a good show as it approaches Earth for an 11-million-mile close encounter on Oct. 20th. Last night it passed by the Double Cluster in Perseus. The contrast between the blue stars of the two clusters and the green atmosphere of the comet was remarkable:

Image
© Michael Jäger of Stixendorf, Austria
Most observers agree that the comet is not yet visible to the naked eye, but it is an easy target for backyard telescopes. In recent nights, astronomers have enjoyed watching Comet Hartley 2 pass a succession of stars and deep-sky objects such as the Pacman nebula and the Double Cluster. Next up is eta Persei (η Per), a 4th-magnitude star that will shine through the comet's atmosphere on Oct 9th and 10th. Details and a sky map are available from from Sky & Telescope.

More images: from Mike Broussard of Maurice, Louisiana; from David A Harvey of Tucson, Arizona; from Tamás Ábrahám of Zsámbék, Hungary; from Nick Howes using the 2 Metre Faulkes North Telescope in Hawaii; from Dr Paolo Candy of Ci.A.O. Cimini Astronomical Observatory - Italy; from Parks Squyres of SaddleBrooke, Arizona; from Gregg Ruppel of Ellisville, MO; from Geir Øye of Ørsta, Norway; from Mohammad Rahimi of Honjan - Esfahan - Iran; from Joe Wheelock of McDonald Observatory, Texas; from Alex Roca of Hortoneda Lleida Spain; from Fredrik Broms of Kvaløya, Norway; from Ehsan Rostamizadeh of Kerman, Iran; from Stefano Moretti of Ravenna, Italy; from Florin Marc of Tg.Mures, Romania