OBSERVING September 2015 French astronomer Pierre Méchain discovered the great spiral galaxy M101 on March 27, 1781; see page 34. In This Section 42 Sky at a Glance 42 Northern Hemisphere Sky Chart 43 Binocular Highlight: A Cygnus Double Delight 44 Planetary Almanac 45 Northern Hemisphere's Sky: Stars for a Moonlit Night 48 Celestial Calendar 48 It's Uranus-Neptune Season 50 Asteroid Occultations 51 The Moon Occults Aldebaran 52 Exploring the Solar System: The Ashen Light Redivivus 55 Deep-Sky Wonders: A Serpent's Tale 46 Sun, Moon & Planets: Flames at Dawn Additional Observing Stories: PHOTOGRAPH: NASA / ESA / K. KUNTZ, F. BRESOLIN, J. TRAUGER, J. MOULD, Y.-H. CHU / STSCI / CFHT / J.-C. CUILLANDRE / COELUM / G. JACOBY, B. BOHANNAN, M. HANNA / NOAO / AURA / NSF 58 Cygnus in the City 26 September's Total Lunar Eclipse SkyandTelescope.com September 2015 41http://www.SkyandTelescope.com