Gregory Gross

Urban Observing List for Small Telescopes

Yes, there is no substitute for a large-aperture telescope under dark skies. But for many of us, small telescopes are more financially accessible and more convenient to set up, use, and enjoy. And the lengthy round-trip drive out to a dark-sky site may take as much time if not longer than the observing session itself.

Having consulted George Robert Kepple and Glen W. Sanner's Night Sky Observer's Guide, Rod Mollise's Urban Astronomer's Guide, and the Astronomical League's Urban Observing Program lists—and drawing upon my experience in my own backyard—this is my selection of objects that are visible in small telescopes (around four inches of aperture) under city skies:

NameTypeVisual Magnitude (and Surface Brightness)Size/SepRA and Declination
Eta Cassiopeiae / AchirdDouble Starm3.4, m7.512.9"00h 49m 57°
M31 / Andromeda GalaxyGalaxym3.4v  SB 13.6185' x 75'00h 42m 41°
M32Galaxym8.1v  SB 12.711' x 7.3'00h 42m 40°
NGC 457 / Owl ClusterOpen Star Clusterm6.4v13'01h 19m 58°
Gamma Arietis / MesartimDouble Starm4.8, m4.87.8"01h 53m 19°
Alpha Ursae Minoris / PolarisDouble Starm2.0, m8.218.4"02h 31m 89°
NGC 869 and 884 / Double ClusterOpen Star Clusterm5.3v (NGC 869), m6.1v (NGC 884)29', 29'02h 20m 57°
Gamma Andromedae / AlmachDouble Starm2.3, m5.59.8"02h 03m 42°
M34Open Star Clusterm5.2v35'02h 42m 42°
Melotte 20 / Alpha Persei AssociationOpen Star Clusterm1.2v185'03h 22m 49°
M45 / PleiadesOpen Star Clusterm1.2v110'03h 47m 24°
Kemble 1 / Kemble's CascadeAsterism150'04h 07m 62°
Melotte 25 / HyadesOpen Star Clusterm0.5v330'04h 27m 16°
M38Open Star Clusterm6.4v21'05h 28m 35°
M36Open Star Clusterm6.0v12'05h 36m 34°
M37Open Star Clusterm5.6v20'05h 52m 32°
Lambda Orionis / MeissaDouble Starm3.5, m5.64.4"05h 35m 9°
Collinder 70 / Orion's BeltAsterism05h 35m -1°
Sigma OrionisQuadruple Starm4.0, m10.311.4"05h 38m -2°
M42 / Orion NebulaDiffuse Nebulam4.0v90'05h 35m -5°
M43 / De Mairan's NebulaEmission Nebulam9.0v20'05h 35m -5°
Theta Orionis / TrapeziumQuadruple Starm5.1, m6.7, m6.7, m7.98.8", 13.4"05h 35m -5°
Iota OrionisTriple Starm2.8, m7.311.3"05h 35m -5°
Gamma LeporisDouble Starm3.7, m6.396.3"05h 44m -22°
M35Open Star Clusterm5.1v28'06h 08m 24°
NGC 2264 / Christmas Tree ClusterOpen Star Clusterm3.9v20'06h 41m 9°
Beta MonocerotisTriple Starm4.7, m5.2, m6.12.8", 7.3"06h 28m -7°
M41Open Star Clusterm4.5v38'06h 46m -20°
Alpha Geminorum / CastorDouble Starm1.9, m2.94.0"07h 34m 31°
M50Open Star Clusterm5.9v16'07h 03m -8°
M47Open Star Clusterm4.4v29'07h 36m -14°
M46Open Star Clusterm6.1v27'07h 41m -14°
Iota CancriDouble Starm4.2, m6.630.5"08h 46m 28°
M44 / Beehive ClusterOpen Star Clusterm3.1v95'08h 40m 19°
M81 / Bode's GalaxyGalaxym6.9v  SB 13.024' x 13'09h 55m 69°
M82 / Exploding GalaxyGalaxym8.4v  SB 12.812' x 5.6'09h 55m 69°
Gamma Leonis / AlgiebaDouble Starm2.2, m3.54.4"10h 20m 19°
Alpha Canum Venaticorum / Cor CaroliDouble Starm2.9, m5.519.4"12h 56m 38°
Melotte 111 / Coma Star ClusterOpen Star Clusterm1.8v275'12h 25m 26°
24 Comae BerenicesDouble Starm5.2, m6.720.3"12h 35m 18°
Zeta Ursae Majoris / Mizar and AlcorDouble Starm2.3, m4.014.4"13h 23m 54°
M3Globular Star Clusterm5.9v16.2'13h 42m 28°
Mu Bootis / AlkaluropsTriple Starm4.3, m7.0, m7.6108.3", 2.3"15h 24m 37°
Zeta Coronae BorealisDouble Starm5.1, m6.06.3"15h 39m 36°
M5Globular Star Clusterm5.7v17.4'15h 18m 2°
M13 / Great Hercules ClusterGlobular Star Clusterm5.7v16.6'16h 41m 36°
Kappa Herculis / MarfakTriple Starm5.3, m6.528.4"16h 08m 17°
Beta Scorpii / GraffiasDouble Starm2.6, m4.913.6"16h 05m -19°
Rho OphiuchiDouble Starm5.3, m6.03.1"16h 25m -23°
Alpha Scorpii / AntaresDouble Starm1.2, m5.42.9"16h 29m -26°
Nu DraconisDouble Starm4.9, m4.961.9"17h 32m 55°
M92Globular Star Clusterm6.4v11.2'17h 17m 43°
Alpha Herculis / RasalgethiDouble and Variable Starm3.5, m5.44.7"17h 14m 14°
IC 4665Open Star Clusterm4.2v40'17h 46m 5°
Epsilon Lyrae / Double DoubleDouble Starm5.4, m6.5; m5.1, m5.32.6", 2.3"18h 44m 39°
Zeta LyraeDouble Starm4.3, m6.043.7"18h 44m 37°
Delta (1 and 2) LyraeDouble Starm5.6, m9.3; m4.5, m11.2174.6"; 86.2", 2.2"18h 54m 36°
M57 / Ring NebulaPlanetary Nebulam8.8v> 1.18'18h 53m 33°
Theta Serpentis / AlyaDouble Starm4.6, m5.022.3"18h 56m 4°
M11 / Wild Duck ClusterOpen Star Clusterm5.8v13'18h 51m -6°
16 CygniDouble Starm5.9, m6.239.3"19h 41m 50°
Delta CygniDouble Starm2.9, 6.32.5"19h 45m 45°
Beta Cygni / AlbireoDouble Starm3.1, m5.134.0"19h 30m 27°
M27 / Dumbbell NebulaPlanetary Nebulam7.3v5.8'19h 59m 22°
Collinder 399 / CoathangerAsterismm3.6v60'19h 25m 20°
Omicron CygniTriple Starm3.6, m4.8, m6.7107.0", 337.5"20h 13m 46°
M29 / Cooling TowerOpen Star Clusterm6.6v6'20h 23m 38°
NGC 6871Open Star Clusterm5.2v20'20h 05m 35°
Gamma DelphiniDouble Starm4.3, m5.19.6"20h 46m 16°
Alpha Capricorni / Al Giedi (The Goat)Double Starm3.6, m4.2378"20h 18m -12°
Beta Capricorni / DabihTriple Starm3.4, m6.2205.3"20h 21m -14°
M39Open Star Clusterm4.6v31'21h 32m 48°
M15Globular Star Clusterm6.0v12.3'21h 30m 12°
M2Globular Star Clusterm6.4v12.9'21h 33m 0°
Delta CepheiDouble and Variable Starm3.48 to m4.37 in 5.4 days41.0"22h 29m 58°