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Out there

Mid-summer Milky Way meanderings

Mark Wagner

NGC 6946, face-on spiral galaxy in Cepheus, sketched by Peter Natscher.

NGC 6934, globular cluster in Delphinus, sketched by Peter Natscher


Summer is flying by — have you used your telescope this month? Conditions have been about as good as they get, so don't miss out. Nights are lengthening and a mix of deep and galactic treats await us. And a reminder, CalStar is coming up new moon next month at Lake San Antonio — a wonderful dark sky site that is a very easy ride 2.5 hours down highway 101 just south of King City. See

Our swath of sky this month, rising in the east for 3rd quarter and new moon, is between right ascension 20.31 and 22.47 — from Cepheus through Cygnus, Lacerta, Vulpecula, and south into Pegasus, Delphinus and Aquarius.

Start with the fine double star Beta Cephei, the northeastern star in the "box" that defines the main body of the constellation. The primary is very bright white at mag 3.8 with a yellow or rose colored companion west of and close to the primary, significantly dimmer at mag 7.8.

Cross the "box" of Cepheus to check out Delta Cephei, which I immediately saw as an Albiero clone. The double sits in an area rich in open clusters; spend some time there. Delta's primary shines at mag 4 and is a nice gold/white color, not quite as rich gold as Albiero. The companion is very blue and sits a wide 42" south.

Move to the center of the box to the double star Xi Cephei. I saw this as a bright white primary with a dimmer yellowish-red companion almost 2" west. Can you split the third component apart from the secondary, just 1" to its east?

Just 2.2 degrees south-southwest is open cluster NGC 7160. Jeff Gortatowsky observed it and wrote "This cluster appears as a small thin cluster of some 10-20 members. It's somewhat spread out approximately east to west."

Just under ten degrees west-southwest, across Alpha Cephei, is a real treat in a darker skies, NGC 6946, a fine spiral galaxy. Add to that an outstanding open cluster, NGC 6339, not even 40 arcminues northwest. Two great objects in one low power field of view!

Use Alpha Cygni and Alpha Cephei as guide stars, placing the southern outer ring of a Telrad circle on the center point between the two stars. You should be close to NGC 7008 — a bright planetary nebula. It appears elongated slightly NNE-SSW and perhaps annular. There is a very bright knot on the northern edge and a pair of stars almost touching the southern edge.

Let's move 12 degrees east into Lacerta, to the large open cluster NGC 7243. At 70x it is large, amorphous, and has approximately 25 bright stars with many dim but resolvable other components. Note the three groups — one of 3 stars, another with 15 and the third with about 9. Empty lanes run NNE-SSW between the three sections.

Next move 3.75 degrees south-southwest to NGC 7209, a fun mag 6.7 open cluster. It contains about 12 brighter stars with many more dimly forming a haze around and through the brighter members. A brightish star sits 14' west-northwest and a dimmer one 12' south of the cluster. This cluster is a nice view.

13.5 degrees southeast is a favorite — NGC 7331 in Pegasus. This beautiful spiral is usually a test from my backyard. On a good night it is an easy target, showing the extent of the spiral arms. In larger aperture at a dark site you may glimpse three other small galaxies just east of the spiral.

7 degrees west-southwest is NGC 7217, just off SAO 72077, a double with two bright components. The galaxy lies outside the opening of a large "V" of stars, the brightest being mag 6.3. A brightish star lies southeast of the galaxy, and the galaxy itself is fairly round, perhaps a spiral, elongated in a northeast-southwest direction. NGC 7217 is distinct at mag 10.1 and SB 12.7.

NGC 6940 in Vulpecula is another easy to locate and surprising open cluster. From 39 Cygni cross to 41 Cygni and go the same distance beyond. This open is gorgeous! Big, bright and rich with a stream of stars running from the northwest to the southeast. This one could have easily replaced some of the tiny Messier open clusters! A real treat.

We're now on the way to Delphinus, and NGC 6934. The globular, while a poor cousin of the big bright Messier globulars, is still a pleasing find, and is unmistakable. A bright star sits close by to the object's west, with two more stars still further to the west.

Finish with NGC 7009, which some will recognize as the Saturn Nebula. I was able to find it, above Capricornus' "bikini," just west of the bellybutton star (Nu Aquarii or 13 Aquarii). At 138x it appeared small, oblate and somewhat green-grey. I had no trouble identifying it, even at 72x it was definitely non-stellar.

It is a short drive to the local dark(er) sky sites. Friendly and helpful observers can be found at them nearly any good night. So treat yourself — pack up some warm clothes, thermos of coffee, your scope, and get out there!

BetaDbl Str21h 28m +70 05 Cep
XiDbl Str22h 03m+64 06 Cep
NGC 7160OC21h 53m +62 36 Cep
NGC 6946GX20h 34m+60 09 Cep
DeltaDbl Str22h 29m+58 05 Cep
NGC 7008PN21h 00m+54 32 Cyg
NGC 7243OC22h 15m+49 53 Lac
NGC 7209OC22h 05m+46 30 Lac
NGC 7331GX22h 37m+34 24 Peg
NGC 7217GX22h 07m+31 21 Peg
NGC 6940OC20h 34m+28 18 Vul
NGC 6934GC20h 34m+07 24 Del
NGC 7009PN21h 04m-11 21 Aqr


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