Sky & Telescope - August 2020 - 55

NGC 6814: ERIC A FRICA / A DA M BLOCK / NOAO / AUR A / NSF;
POSS M OSAIC: POSS-I / STSCI / CA LTECH / PA LO M A R OBSERVATORY

southwest by a 3′ triangle of 8th- and
10th-magnitude stars. To the northeast,
Barnard 129 is inky, but it's not as well
framed with stars as its companions and
appears only semidetached from B127.
The whole sooty arc spans a mere 22′.
The distances to most dark nebulae
aren't well determined. A 2006 study
by Gopinathan Maheswar and Harish
Chandra Bhatt in the Monthly Notices
of the Royal Astronomical Society places
B127 at 590 ± 110 light-years and B129
at 650 ± 130 light-years. We could reasonably assume that B130 is at a comparable distance.
Sliding 29′ southeast from V Aquilae takes us to the planetary nebula
NGC 6751. The nebula and star share
a ﬁeld of view through my 130-mm
refractor at 63×, with NGC 6751 presenting a tiny disk. It becomes a sizable
spot at 102×. At 234× the disk has a
dimmer center that harbors an elusive
central star, while the annulus seems
a little brighter in the southeast. Two
very faint stars bracket the nebula. The
slightly brighter one is 23″ east and a
bit north, the other is 38″ west and a bit
north. The planetary's central star looks
about as bright as the closer star.
NGC 6751 is a cute little robin's-eggblue disk in my 15-inch scope at 49×,
offering a lovely color contrast with V
Aquilae. At 248× the nebula's annulus is
a fat ring roughly 25″ across.
Under some conditions NGC 6751
displays a bright center that can be
mistaken for a star. If so, try higher
magniﬁcations to pluck out the true
central star, which is much fainter.
NGC 6751 is sometimes called the
Dandelion Puff Ball, and it looks very
much like the head of a dandelion gone
to seed in the remarkable Hubble image
shown on page 56.
The dark nebula Barnard 134 sits 21′
southeast of NGC 6751. It covers about
4½′ through my 130-mm refractor at
63×, and the two disparate nebulae share
the ﬁeld of view. Maheswar and Bhatt
put B134 at the same distance as B129.
X The dark nebulae near the carbon star V
Aquilae show particularly well in this red-plate
mosaic assembled from the first National Geographic - Palomar Observatory Sky Survey.

Dropping 40′ south-southwest from
B134, we come to Barnard 133. In my
130-mm refractor at 48×, it's a fairly
obvious 8½′ × 3½′ oblong of darkness tipped northwest. Just beyond
the nebula's edge, south of center,
a 5′-tall-asterism of nine faint stars
reminds me of the blocky numeral 8 on
a digital clock. Off the opposite side of
the nebula is Teutsch J1906.4-0647,
discovered by Philipp Teutsch, a participant in the former Yahoo group known
as the Deep Sky Hunters. Once deemed
a possible open cluster, the group is now
known to be an asterism. It's a challenging collection of stars to observe,
and my 10-inch reﬂector at 299× shows
its brightest members as a daisy chain
of several faint to extremely faint stars
draped along the shallow curve of an
east-west garland about 2′ long.

S The face-on spiral galaxy NGC 6814
requires relatively large apertures in order to
reveal its arms in the eyepiece.

Next, we'll set sail for the tiny
planetary nebula IC 4846. To locate it,
head 1° southeast from the blue-white,
5th-magnitude star 20 Aquilae to a
7th-magnitude, east-west pair of deepyellow stars ½° apart. IC 4846 dangles
21′ south of the eastern member of the

B129

B127
B130

6751

B134

Teutsch
J1906.4-0647

B133

sk yandtelescope.org * AUGUST 2 02 0

http://www.skyandtelescope.org

Sky & Telescope - August 2020

Table of Contents for the Digital Edition of Sky & Telescope - August 2020