Kurt, Thanks for that diagram.  I played with it a bit and thought it was interesting how Lulin’s orbit around the sun brought it so close to the earth on a single pass.   I can’t remember the name of the comet now but back in 03 - 04 time frame there was a comet that came in fairly close to earth, brightened on the way in, went around the sun in opposition to earth, came back out around by earth again on it’s way out.    Because the orbits can vary so much depending where the earth is in relation to the comet’s orbit as it goes around the sun, it is fun to see a diagram as you pointed out.   Thanks   Jim   --- On Tue, 2/3/09, Canopus56 <canopus56@yahoo.com> wrote: From: Canopus56 <canopus56@yahoo.com> Subject: Re: [Utah-astronomy] Comet Lulin on 2/3/09 To: "Utah Astronomy List Serv" <utah-astronomy@mailman.xmission.com> Date: Tuesday, February 3, 2009, 3:27 PM I observed it this morning at 5:15am from Little Mtn with a 60mm refractor at 21x and 77x.  At 77x, I could see  slight hint of the extended halo shown in Tyler's image and in other online images.  The bright nucleus was also visible.  As noted in my prior correction, I erred in my comment that we are looking end-on at the comet.  We are looking at it from the side.  See orbit diagram at http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=C%2F2007+N3&orb=1 - Kurt P.S. - Little Mtn was too cold to be useable this morning.  Although the temperature was -2C, there was a slight breeze from which there was no shelter.  The wind chill drove me home after 15 minutes. _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://gallery.utahastronomy.com Visit the Wiki: http://www.utahastronomy.com