he constellation Sagittarius the Archer ranks 15th in Michael E. Bakich is a senior editor of Astronomy and author of 1,001 size and 35th in overall brightness (the number of vis- Celestial Wonders to See Before You Die (Springer, 2010).

ible stars per unit area) out of the sky’s 88 star patterns. Mitch and Michael Dye/Adam Block/NOAO/AURA/NSF (NGC 6818); Anthony Ayiomamitis (M18); Bob Fera (M17); Dean salman But many observers would rank it at the top of the heap (M24); michael sidonio (ngc 6589); Adam Block/Mount Lemmon SkyCenter/University of Arizona (ngc 6590); Adam Block/ 40 deep-sky targets in NOAO/AURA/NSF (NGC 6537); Anthony Ayiomamitis (M23); lisa dombrow/phil terry/adam block/noao/aura/nsf (NGC 6445); with regard to fascinating deep-sky treats. You’ll find Anthony Ayiomamitis (M21); Daniel Verschatse/Antilhue Observatory (M20); Adam Block/Mount Lemmon SkyCenter/ University of Arizona (IC 1274); R. Jay GaBany (M8); al kelly (NGC 6520); Adam Block/Mount Lemmon SkyCenter/University of no fewer than 15 Messier objects here — four more than in any Arizona (NGC 6522); Adam Block/Mount Lemmon SkyCenter/University of Arizona (NGC 6563); Harel Boren (M28); Bernhard T Hubl (M22); Daniel Verschatse (M55); Chuck Kimball (NGC 6822); Astronomy: Richard talcott and Roen Kelly (Finder Chart) other star figure. And that’s just the beginning. You also will find many standouts from the NGC, IC, and Barnard cata- Sagittariu s logs. Here are 40 of my favorites. by Michael E. Bakich The Archer contains a dizzying variety of dazzling objects. 7 10 1 2 3 4 5 6 8 9 The Small 11 12 The Swan Nebula Sagittarius Star The Little Gem M25 (IC 4725) M70 (NGC 6681) NGC 6645 NGC 6638 M18 (NGC 6613) (M17) NGC 6717 NGC 6716 Barnard 92 NGC 6589 Magnitude: — Cloud (M24) (NGC 6818) Magnitude: 4.6 Magnitude: 7.9 Magnitude: 8.6 Magnitude: 9.0 Magnitude: 6.9 Magnitude: 9.3 Magnitude: 7.5 Magnitude: 2.5 Magnitude: — Magnitude: — Size: 20' by 15' Magnitude: 9.3 Size: 32' Size: 7.9' Size: 10' Size: 7.3' Size: 10' Size: 5.4' Size: 10' Size: 95' by 35' Size: 12' Size: 5' Type: Emission nebula Size: 48" Type: Open cluster Type: Globular cluster Type: Open cluster Type: Globular cluster Type: Open cluster Type: Globular cluster Type: Open cluster Type: Star cloud Type: Dark nebula Type: Reflection nebula Type: Planetary nebula 7 M17 13 1 NGC 6818 4 NGC 6645 40 NGC 6590 6 M18 Magnitude: — 11 Barnard’s Galaxy υ Barnard 92 Size: 11' (NGC 6822) Type: Reflection nebula Magnitude: 8.8 40 NGC 6822 15 M23 10 M24 Size: 15.5' by 13.5' Type: Irregular galaxy 2 M25 14 NGC 6537 14 ρ1 12 NGC 6589 16 NGC 6445 The Red Spider ρ2 Nebula 39 9 NGC 6716 13 NGC 6590 17 NGC 6440 (NGC 6537) M75 (NGC 6864) μ Magnitude: 11.6 Size: 1.5' Magnitude: 8.5 1 Size: 6' ξ Type: Planetary nebula Type: Globular cluster π ξ2 18 M21 SAGITTARIUS 15 ο 19 M20 38 37 2 M23 (NGC 6494) –20° ν 1 20 IC 1274 M55 (NGC 6809) M22 (NGC 6656) ν 21 M8 Magnitude: 5.5 8 NGC 6717 36 NGC 6642 Size: 27' Magnitude: 6.3 Magnitude: 5.1 22 Type: Open cluster Size: 19' Size: 24' 37 M22 34 M28 NGC 6559 Type: Globular cluster Type: Globular cluster 23 NGC 6544 λ 16 χ3 35 36 24 NGC 6553 The Box Nebula M54 (NGC 6715) NGC 6642 39 M75 5 NGC 6638 (NGC 6445) Magnitude: 7.6 Magnitude: 9.1 χ1 ψ σ Magnitude: 11.2 Size: 9.1' Size: 5.8' φ Size: 34" 52 Type: Planetary nebula Type: Globular cluster Type: Globular cluster OPHIUCHUS 25 NGC 6520 34 17 M28 (NGC 6626) τ NGC 6440 Magnitude: 6.8 δ Magnitude: 9.2 ω Size: 11.2' γ Size: 4.4' Type: Globular cluster Type: Globular cluster 30 NGC 6624 26 NGC 6522 35 M54 CAPRICORNUS 59 ζ 27 NGC 6558 33 62 18 The Chandelier SCORPIUS M21 (NGC 6531) Cluster 3 M70 31 M69 28 NGC 6569 Magnitude: 5.9 (NGC 6723) Size: 13' Magnitude: 7.0 –30° Type: Open cluster Size: 11' 38 29 Type: Globular cluster M55 NGC 6563 32 NGC 6652 18h 19 19h ε 32 The Trifid Nebula NGC 6652 (M20) Magnitude: 8.6 20h Magnitude: — Size: 6' Size: 20' Type: Globular cluster η Type: Emission nebula 33 NGC 6723 31 20

M69 (NGC 6637) 30 29 28 2 27 26 25 24 23 22 21 IC 1274 Magnitude: 7.6 θ Magnitude: — NGC 6624 NGC 6563 NGC 6569 NGC 6558 NGC 6522 The Castaway NGC 6553 The Starfish NGC 6559 The Lagoon Size: 7.1' Magnitude: 7.9 Magnitude: 11.0 Magnitude: 8.6 Magnitude: 9.3 Magnitude: 8.3 Cluster Magnitude: 8.1 Cluster Magnitude: — Size: 5' Type: Globular cluster θ1 (NGC 6520) (NGC 6544) Nebula (M8) Type: Reflection nebula Size: 8.8' Size: 48" Size: 6.4' Size: 4.2' Size: 5.6' Size: 9.2' Size: 8' Magnitude: — Magnitude: 7.6 Magnitude: 7.8 Type: Globular cluster Type: Planetary nebula Type: Globular cluster Type: Globular cluster Type: Globular cluster Type: Globular cluster Type: Emission nebula Size: 90' by 40' Size: 6' Size: 9.2' Type: Emission nebula Type: Open cluster Type: Globular cluster

70 Astronomy • August 2013 find descriptions of each object at www.Astronomy.com/toc. α