Brent, We used the same demo teaching the teachers as well. I remember you pointing a flashlight at my shiny head as we walked in circles while everyone watched my shadow go backwards on the walls behind me. Good memories! -----Original Message----- From: utah-astronomy-bounces@mailman.xmission.com [mailto:utah-astronomy-bounces@mailman.xmission.com] On Behalf Of Brent Watson Sent: Tuesday, March 26, 2013 1:19 PM To: Utah Astronomy Subject: Re: [Utah-astronomy] Replicating a hissing meteor Long ago, in the early 90s, when Wayne Sumner and I gave away telescopes to schools, I demonstrated retrograde motion in a SLAS meeting. It involved setting everyone in a large circle and then replicating a portion of the solar system. I still believe that helped people understand why there is retrograde motion. _______________________________________________ Utah-Astronomy mailing list http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Send messages to the list to Utah-Astronomy@mailman.xmission.com The Utah-Astronomy mailing list is not affiliated with any astronomy club. To unsubscribe go to: http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Then enter your email address in the space provided and click on "Unsubscribe or edit options".