Facing North WHEN TO USE THIS MAP Early August - 11 pm* Late August - 10 pm* Early September - 9 pm* Late September - 8 pm* 7h h +60° 10 CAM M82 C PE IA _ S ` TES BOÖ b + +60° s M13 _ a M92 CORONA BOREALIS Arcturu EU _ DRA CO SERP (CAP ENS UT) _ M20 n US SA G IT TA RI CORONA AUSTRALIS A _ ` es tar n Moon A Sept 13 M8 ¡ M7 h p S -40° n oo 0 M pt 1 e S R S L H C O R _ E C P L I T M4 16h P I U 19h I C S Fa ci n STAR MAGNITUDES -1 0 1 2 3 4 Facing South SYMBOLS Galaxy 9/12: William Herschel observes barred spiral galaxy NGC 7753 in Pegasus, one of 13 deepsky objects he discovers that night, 1784 Double star 9/12: Charles Messier launches his catalogue with M1, the Crab Nebula, 1758 Variable star Open cluster 9/14: Nicolas Louis de Lacaille discovers 47 Tucanae, the second largest and second brightest globular cluster, 1751 Diffuse nebula 9/14: Abraham Lincoln takes an evening break from preparing for his upcoming debate with Stephen Douglas to watch Comet Donati, 1858 Globular cluster 9/17: William Herschel discovers Saturn's moon Mimas, 1789 Planetary nebula 9/23: Johann Galle discovers Neptune, 1846 SK Y WATCH 2021 45 Facing West PH l S C M23 S SE H IU U SW Littl D i p p e +80° er O ` IU P M22 m R n Ve M17 M25 O g CE SI d HERCULES n R -20° n M3 ` _ ci A ci NU n M c & izar Alc or _ AS US U OR ci ¡ URS MIN A OR S LE Q Fa IC Satu r VIRGO Polaris ` NU UU EQ _ A PR O SCUTUM T 2 M1 0 M1 M11 ` M Se oon pt 17 U E Q A us SERPENS (CAUDA) _ MA CO ICES EN R E B S I NE IC C A AT N VE b D Big ipp er Albireo HI LP _ Altair _ IB Fa S le ub er Do lust C C Y G N U S DE M15 ¡ TA M5 +80° Deneb _ M39 TA ` PEGASUS _ +20° GIT AQU ILA er Fa M81 LA CE R ED A Great Square of Pegasus 7 SA h 13 _ EU go ND 1 RO M M3 _ n oo 20 M pt Se CA M RS Al _ a PE IS A 3 M2 pit 22h 51 DAL ` M3 1h ` M57 0° Ju g ` U M RS AJ A O R PA R a T RI A NG UL UM PIS CE S Facing East LY R A ¡ Vega _ Zenith g ELO W E July N g N Map instructions can be found on page 9. 4h *Daylight-saving time SE P T E M BE R | 2021 SK YC H A RT