Objects & Observing Sites

There are many kinds of deep sky objects to see: the Moon, planets, stars, double stars, open star clusters, globular clusters, galaxies, nebulae, and planetary nebulae.

Different size aperture and types of telescopes can give you different views of objects. The larger the aperture and the darker the skies the better most deep sky objects will look. PAS has come up with some of our favorite deep sky telescopic objects that look good depending on the size of the scope and the darkness of the night sky. (Darkness of the sky is shown in Bortle numbers. Bortle 1-3 is darkest, many miles away from any lights, like the antennas location Bortle 2. Bortle 4-5 is suburban or outskirts of the valley like Cave Creek or Carefree. Bortle 6-9 is inside the Phoenix city limits with various degrees of light pollution.)

5 inch refractor telescope:

• Anytime: The Moon and five naked eye planets; Mercury, Venus, Mars, Jupiter and its moons and Saturn and its moons

• Fall: NGC 7009 Saturn Planetary Nebula outskirts of Valley (Bortle 4-5)

• Winter: NGC 7662 Blue Snowball Planetary Nebula , NGC 2169 “XY” star cluster outskirts of valley (Bortle 4-5)

• Spring: Stargate asterism 2 nested triangles outskirts of valley (Bortle 4-5) NGC 3242 Ghost of Jupiter Planetary Nebula dark skies like the antennas area (Bortle 2)

• Summer: deep red carbon star 1 Lyrae, Collinder 399 Coat Hanger asterism outskirts of valley (Bortle 4-5)

6 inch Dobsonian reflector telescope:

• Fall: Double Cluster in Perseus, Andromeda Galaxy M31 outskirts of Valley (Bortle 4-5)

• Winter: Pleiades Open Cluster M45, Orion Nebula M42 in Phoenix (Bortle 6-8)

• Spring: Beehive Open Cluster M44, Hercules Globular Cluster M13 (Bortle 4-5)

• Summer: Ptolemy’s Open Cluster M7 in Scorpius (Bortle 4-5) Lagoon Nebula M8 dark sky (Bortle 2)

8 inch Newtonian reflector telescope:

• Fall: Gamma Andromeda blue and gold double star in Phoenix (Bortle 6-8)

• Winter: Orion Nebula M42 outskirts of the Valley (Bortle 4-5)

• Spring: M81 and M82 galaxies dark sky like Antennas location (Bortle 2)

• Summer: M13 globular cluster outskirts of Valley (Bortle 4-5)

9 ¼ inch Schmidt Cassegrain telescope:

• Fall: Albireo and Gamma Andromeda double stars blue and gold in Phx (Bortle 6 8), Stephan’s quintet of galaxies Hickson 92 (NGC’s 7317, 7318a, 7318b, 7319,7320) dark sky area (Bortle 2)

• Winter: Orion Nebula and Running Man Nebulae M42 &M43 in Phx (Bortle 6-8) M35 Open Cluster Phx (Bortle 6-8)

• Spring: Omega Centauri Globular Cluster southern outskirts of Phoenix (Bortle 4-5), M35 Open Cluster in Phoenix (Bortle 6-8)

• Summer: Swan Nebula M17 (use OIII filter) and Lagoon Nebula M8, if south of the valley (Bortle 4-5)

14 inch Dobsonian reflector telescope:

• Fall: Perseus double cluster Phx (Bortle 6-8), M37 open cluster outskirts of valley (Bortle 4-5), M17 & M20 Nebulae and Open Clusters NGC 7789 and M11 Wild Duck in dark sky area like antennas (Bortle 2)

• Winter: Orion Nebula M42 in Phx (Bortle 6-8), Andromeda Galaxy M31 outskirts of Valley (Bortle 4-5), Open Clusters M41 and M50 dark area (Bortle 2)

• Spring: M81 and M82 galaxies outskirts of valley (Bortle 4-5) M51 Whirlpool galaxy and M5 &M13 globular clusters, and Virgo region galaxies (M86 and surrounding area) all in dark area (Bortle 2)

• Summer: M57 Ring Nebula outskirts of Valley (Bortle 4-5) , NGC 6826 Blinking Planetary Nebula, Helix Nebula NGC 7293, Veil Nebula Caldwell 33/34, Sculptor Galaxy NGC 253, M27 dumbell nebula dark area (Bortle 2)

Even though most night sky objects look best in telescopes, binoculars can show galaxies, nebulae, globular clusters, open clusters, stars, double stars, the moon, some comets and Jupiter with its 4 Galilean Moons. 7 x 35 or 7 x 50 are the smallest recommended, and the standard 10 x 42 or 10 x 50 are even better. Astronomy binoculars like 20 x 80, or 25 x 100 can be very heavy and require a tripod to hold steady. The first number is the power or magnification, and the second number is the diameter of the 2 big lenses in millimeters. The bigger the diameter, the easier it is to see dimmer objects.

The following are some of the favorite deep sky objects PAS members enjoy with binoculars. We have listed the season of the year and the constellations to help locate them.

• Fall: Andromeda Galaxy M31; Milky Way Galaxy; M15 Globular Cluster in Pegasus; Perseus Double Open Star Clusters

• Winter: Pleiades Open Star Cluster M45 in Taurus; Orion Nebula M42; Open Star Cluster M35 in Gemini; M36 Open Star Cluster in Auriga; M37 Open Star Cluster in Auriga; M38 Open Star Cluster in Auriga; Betelgeuse in Orion redorange star; Rigel in Orion blue-white star; Aldebaran in Taurus red giant star

• Spring: Beehive Open Star Cluster M44 in Cancer; M50 Open Star Cluster in Monoceros; M41 Open Star Cluster in Canis Major; Mizar Double star in Ursa Major

• Summer: Lagoon Nebula M8 in Sagittarius; Trifid Nebula M 20 in Sagittarius; Hercules Globular Cluster M13; M25 Open Cluster in Sagittarius; M22 Globular Cluster in Sagittarius; Delta Lyra,red/blue double star; Epsilon Lyra , wider components of the double double star; “False Albireo” Alpha and 8 Velpeculae double star; Omicron 1 and 2 blu/orange double star; 31 Cygni, wide triple star; Deneb in Cygnus blue-white star; Summer Triangle of 3 stars Deneb in Cygnus, Vega in Lyra, Altair in Aquila; Coll399 in Vulpecula “Coat Hanger” Asterism group of stars

The darkness of the night sky can be measured in Bortle Units or with a Dark Sky Meter. In February 2001, John Bortle published his famous scale in Sky and Telescope Magazine. Bortle 1 is the darkest sky possible. Bortle 5 is where the Milky Way is faintly visible to the naked eye. Bortle 9 is very bright inner city skies with only a few very bright stars visible. PAS has taken Bortle readings using a Sky Quality Meter about 2 hours after sunset with no moon or clouds present at various locations. This can help you find a dark sky site near you. The lower the Bortle number, the darker the skies and the more objects can be seen. A 6 or 8 inch diameter telescope at a Bortle 1 or 2 site can look as good as a 16 or 18 inch scope at a Bortle 5 or 6 site.

• Bortle 1.0 18 miles south of Jacobs Lake, 22 miles north of north rim of Grand Canyon : Map Link https://goo.gl/maps/mEueApUHSBngjVD79

• Bortle 1.5 Kaibab lodge 18 miles north of north rim of Grand Canyon

• Bortle 1.5 Wupatki/Doney Mountain Lunch/View Area about 45 minutes north of Flagstaff off route 89: Map Link https://goo.gl/maps/BGPfWx732xc6Vk6x6

• Bortle 1.5 Southwestern Research Station, Portal AZ

• Bortle 1.9 Moran Point South Rim of Grand Canyon Bortle 2.0 Eastern limits of Munds Park about 20 miles south of Flagstaff: Map Link https://goo.gl/maps/WC6jNcx9kxEgcmGK6

• Bortle 2.0 Antenna’s air field about 98 miles west of Central Phoenix N of I-10

• Bortle 2.0 Hovatter Rd Antenna’s site about 100 miles west of Central Phoenix : Map Link https://goo.gl/maps/ExigYzfoffeMFmfLA

• Bortle 2.0 Tonto National Monument

• Bortle 2.0 Munds Park, south of Flagstaff

• Bortle 2.6 Arcosanti about 60 miles north of Phoenix

• Bortle 2.8 Forest Highlands March, Flagstaff

• Bortle 3.4 Pickett Post trail head about 60 miles SE of Phx off Highway 60 : Map Link https://goo.gl/maps/Uopixr2yRxzsDAsDA

• Bortle 3.9 Four Peaks cookout area 18 miles north from Fort McDowell on Beeline Highway Turn off ~ 33.67803 -111.50200

• Bortle 4.0 Buffalo Park in N Flagstaff: Map Link https://goo.gl/maps/Rk9DakmtF9otijJJ6

• Bortle 4.1 Needle Rock Recreation Area near Rio Verde - can be found at: ~ 33.76764 -111.67004

• Bortle 4.2 Town of Tusayan 5 miles south of Grand Canyon

• Bortle 4.3 Cow Track Ranch in Carefree

• Bortle 4.3 Spur Cross Ranch Park, Cave Creek: https://www.maricopacountyparks.net/park-locator/spur-cross-ranch-conservation-area

• Bortle 4.3 New River

• Bortle 4.3 Robbins Butte East of Buckeye 40 miles SW of Phoenix

• Bortle 4.6 McDowell Mountain Park: https: www.maricopacountyparks.net/mcdowell-mountain-regional-park

• Bortle 5.0 Paradise Valley Community College Black Mountain Campus North Valley

• Bortle 5.7 South Mountain Park, Phoenix