no denying it, my family and I are dog people. And we have three to
prove it. All are wonderful…except when one wakes me up at 3 AM to take
a trip outside.
exactly what our American Eskimo, Suzy, did a couple of months ago. Dutifully and bleary-eyed, I let her out to
do what dogs have to do.
But then I made
the mistake of glancing up.
The sky was
clearer and darker than I had seen in recent memory, perhaps still in
aftermath of Hurricane Irene, which had blown through a few days
Above: Autumn star map adapted from the book Star
Watch by Phil Harrington
Above: Finder chart for this month's Binocular Universe.
Chart adapted from Touring the
Universe through Binoculars Atlas (TUBA), www.philharrington.net/tuba.htm
is cheap, so after Suzy came in, I grabbed my 10x50 binoculars and did
mini deep-sky marathon through the constellations Cassiopeia and
Perseus. The views of showcase targets
like M52, NGC
7789, NGC 457, and the Double Cluster were stunning. But what I really enjoyed was wandering off
the beaten path just a bit to survey some of the region’s less
subjects. And that’s exactly what
do in this month’s e-column.
Let’s begin by aiming toward Delta and
Epsilon Cassiopeiae in the constellation’s W. These
3rd-magnitude stars are separated by
just under 5°, and so fit into the same the field.
you see a faint fuzz just east-southeast of the midway point between
them? That’s NGC
663, a striking assembly of some 80 faint stars. Though NGC 663 weighs in at 7th magnitude, it
remains unresolved when viewed through 50-mm binoculars. The brightest cluster suns can be resolved in
my 16x70 binoculars, while my 25x100s show that the stars are bunched
into two asymmetric
Messier somehow missed NGC 663, but he did spot a second cluster
a degree northeast of Delta Cas. We know
it today as M103. M103
holds a footnote in astronomical history
as being the final object in Messier's original catalog. (M104
through M110 were subsequently added in
the 20th century from Messier's unpublished notes.) His words describe M103 as simply "a
cluster of stars."
it’s not very inspirational, Messier's lackluster description
more on his telescope's quality than on M103 itself. Today's amateurs know M103 as a sparkling
collection of stardust set in an arrowhead pattern measuring about 6'
across. Marking the tip of the arrowhead
is the pretty telescopic multiple star Struve 131. Studies conclude that the association between
Struve 131 and M103 is purely circumstantial, with the star lying
and the cluster. If that's the case,
then the brightest cluster star shines at magnitude 10.6, which is too
be resolved through most binoculars.
from Epsilon Cas, scan about 1° northeast to find a V-shaped
asterism of stars
that remind me of a gaggle of geese in-flight. The
5th-magnitude star SAO 12076 leads the
way, followed by 52 and 53 Cas as well as a few fainter goslings. Adding three dim suns just east of 53 appends
a diamond pattern to the end of the flock. Three
of the diamond's stars, including 53
Cas, along with another 20 or so fainter suns, collectively form open
cluster Stock 5. Although
the cluster stars are loosely packed,
you might be able to detect a slightly hazy quality to that diamond,
if you are viewing through at least 12x binoculars.
swing about 8°, or a little more than a binocular field, northward
keystone of four stars formed by 40, 42, 48, and 50 Cas. Take
a careful look inside the keystone for a
dim glow. That's another little-observed open cluster, Collinder
463. Spanning an
area of sky equal in size to the full moon, Collinder 463 is made up of
faint stars lying some 2,100 light years from Earth. The
brightest shine between 8th and 9th
Left: M103, NGC 663, and surroundings are seen in this sketch by Belgian
amateur Rony De Laet through his 15x70 binoculars.
For a labeled version of this sketch, be sure to
Rony’s web site.
next few targets all lie to the east of the Cassiopeia W and
the Double Cluster. After you force
away from that magnificent view, center on a hazy blotch 4.5° to
north-northeast. That’s Melotte
15, the open cluster spawned by
the emission nebula IC 1805. When summed
together, the 40 stars in Melotte 15 shine at magnitude 6.5, bringing
the range of small pocket binoculars. With my 10x50s, I can count half a dozen stars within the
arc-minute span, with the brightest shining about 8th magnitude.
smaller clusters lie to either side of Melotte 15. The first, Markarian 6, is small and easily
missed group. But look carefully and you
might be able to a
faint group of six stars that looks a little like an arrow aimed toward
south. NGC 1027 lies an
equal distance due east of Melotte 15. The
40 stars in this small open cluster look
like a soft glow surrounding a 7th-magnitude sun. Although
all three clusters appear close to
one another in our sky, all three lie at very different distances. According Archinal and Hynes, authors of the
book Star Clusters (Willmann-Bell, 2003), Markarian 6 is the
closest at 1,665
light years away. NGC 1027 comes in
second at 3,950 light years, while Melotte 15 lies a distant 7,200
you can see from the chart above and the list below, this segment of
and adjacent Perseus contain many other star clusters visible through
binoculars, as well as some interesting variable stars. How many others can you find? Give
them a try and let me know!
we meet once again next month under the autumn sky, remember that when
to stargazing, two eyes are better than one.
Harrington is the author of 9 books on
astronomy, including his latest, Cosmic Challenge. Be sure to visit his web site at www.philharrington.net
Harrington's Binocular Universe is copyright 2011 by
Philip S. Harrington. All rights reserved. No reproduction,
in whole or in part, beyond single copies for use by an individual, is
permitted without written permission of the copyright holder.