Sky & Telescope - August 2024 - 26

Celestial Views
cloud as NGC 6603, which was likely too dim for Messier to
observe.
Moving about 5° northeast into Scutum we find a small,
vaguely triangular star cloud around 3° east of the Eagle
Nebula (M16). The cloud has 5th-magnitude Gamma Scuti
at its southwestern corner, where it's particularly bright and
dense. It spans about 2° at its base, which extends eastward
from Gamma then stretches 3½° northward to 5th-magnitude
HD 171391. B312 lies to the cloud's south. The stars of
this Gamma Scuti Cloud (as I call it) fall off markedly to
the east and more gradually to the west, where a small gulf
lies between the star cloud and M16. In my refractor at 25×,
the cloud's bone-white stars fill the field and appear slightly
granular and less uniform than those in M24, but it's still
quite a lovely sight.
Let's move up to the Scutum Star Cloud, an anvilshaped
outcropping 5° long running northwest to southeast
between Beta (β) and Delta (δ) Scuti. The star cloud joins the
broader Milky Way in the southeast. In the northeast it ends
abruptly at the prominent 2°-wide bay of B111, which harbors
two smaller and even darker nebulae, B110 and B113.
To the west, the cloud ends at B103. Larger than M24 and
roughly as bright, the Scutum Star Cloud reveals a splendid
starscape that I can partially resolve with averted vision in my
85-mm refractor at 25×.
On the eastern edge of the Scutum Star Cloud we see the
spectacular M11, the Wild Duck Cluster. Named for its triangular
shape resembling a flock of migrating birds, this 6thmagnitude
open star cluster spans 11′, but it's so packed with
stars that it needs substantial magnification to pull it apart. I
prefer the view of M11 in my Dob fitted with a 13-mm Ethos,
which delivers 92× - the dense cluster of white stars on the
more distant starry background is breathtaking.
About 2.7° south-southeast of M11, look for the planetary
nebula IC 1295 and the globular cluster NGC 6712 about
25′ west-northwest of the nebula. At magnitude 12.5, IC 1295
Gamma Scuti RA 18h 33m Dec. -14° 20′
Object
Type
B312
Dark nebula
Size
100′ × 30′
RA
18h 32.2m
Gamma Aquilae RA 19h 31m Dec. +11° 38′
Object
Type
B337
B142
B143
Dark nebula
Dark nebula
Dark nebula
Size
3′
40′
60′
RA
19h 37.0m
19h 39.7m
19h 41.4m
Sagitta RA 19h 41m Dec. +18° 07′
Object
Type
LDN 731
Dark nebula
Size
30′
26 AUGUST 2024 * SKY & TELESCOPE
looks dim but obvious in my 10-inch. It spans about 1.5′, making
it a little larger than the Ring Nebula (M57). At 92× the
almost-10′-wide, 8.1-magnitude globular appears noticeably
brighter than the pale glow of the planetary. The charts of the
interstellarum Deep Sky Atlas label NGC 6712 as the " Weird
Globular. " The cluster is somewhat peculiar to astronomers as
it appears to have a dearth of low-mass stars compared to other
globulars. Such stars may have been yanked away by external
gravitational forces as the cluster passes through the galaxy.
Moving on, look about 3° northwest of Gamma Aquilae
(Tarazed) to see another pleasing star cloud that spans
4° × 2°. As with the other star clouds described here, it
stretches in a northeast-to-southwest direction. Larger than
M24 but not nearly as scintillating, the Gamma Aquilae
Star Cloud, as I've dubbed it, appears uniform in both my
15×50 binoculars and in my refractor at 25× except for the
single irregular dark nebula, B337, which is about 3′ long and
lies just northeast of center. The cloud fades to the northeast
into the Milky Way. To the west it drops off suddenly in a
region of darkness nearly as large as the star cloud itself. The
southern edge of this dark patch interrupts the starry haze for
about 1°. Southwest of this dark bay lies a protruding patch of
stars about 1° wide that resembles a miniature version of the
Scutum Star Cloud and appears just as bright in my refractor.
While you're exploring here, look about 1½° west of
Gamma Aquilae to take in the inky-dark fingers of B142 and
B143 that comprise the irregular region, a bit less than 1°
long, known as Barnard's E. The view of orange Gamma and
the unmistakable shape of the nebulae deliver a superb sight
in my 85-mm at 25×.
Continuing on our northeasterly route along the Milky
Dec.
-15° 35′
Way let's stop briefly in Sagitta, which harbors a dense star
field next to the Great Rift to the north and east. Barnard
noted this small Sagitta Star Cloud (again, my moniker),
less than 1° across, centered about 12′ north-northeast of a
line between Alpha (α) and Beta Sagittae. Sure enough, as I
aim my refractor with the 13-mm Ethos in this direction, I
see a shimmering patch of unresolved blue-white stars that
sticks out from the broader Milky Way to the east and south.
The dark nebula LDN 731, about as large as the cloud, lies
immediately to its west.
Dec.
+12° 24′
+10° 31′
+11° 00′
The Northern Milky Way
At last we arrive at the Cygnus Star Cloud, the brightest
section of the northern Milky Way and the largest cloud
on this tour. It spans 16° from Beta Cygni (Albireo) in the
southwest to Gamma Cygni (Sadr) in the northeast. To the
northwest it blends into the broader Milky Way; to the southeast
it disappears into the dark nebulae of the Great Rift. We
see this cloud's stars through a gap in interstellar dust in the
Orion-Cygnus Arm of the Milky Way.
The Cygnus Star Cloud looks spectacular even without
RA
19h 38.2m
Dec.
+17° 37′
optics, but it's especially beautiful in my super-wide-angle
2.1×42 binoculars, an ideal instrument for observing it. Near
Albireo the cloud appears orderly, uniform, and mostly unre
Sky & Telescope - August 2024

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