Sky and Telescope - October 2018 - 30

Big, Bold, Bright, Beautiful

OCTOBE R 2 018 * SK Y & TELESCOPE

NGC 6826

16 Cygni

2
20 030
20 20
10

This article is for the tourist. Whether you're new to the
hobby or a hoary veteran, we all have nights when we just
want a light show. When we grow tired of looking for faint
fuzzies, autumn offers a veritable smorgasbord of eye candy
for the spectacle-hungry. Here are some of my favorites,
working more or less from north to south for a couple of
hours after sunset in October.
Let's start with NGC 6543, the Cat's Eye Nebula. This
bright (8th-magnitude) planetary nebula in the neck of
Draco, the Dragon, is one of the most popular planetaries in the northern sky. It's small but bright enough to see
in almost any telescope, and it takes magniﬁcation well, so
crank it up and admire this twist of stellar atmosphere that
has blown off a dying star. It's decidedly oblong and does
indeed look like the elongated pupil of a cat's eye. With some
aperture and steady sky you can see the central star, and
maybe even detect the nebula's greenish color. When you're
looking at the Cat's Eye, you're looking toward the north
ecliptic pole, which means you're looking straight up out of
the plane of the solar system.
As long as we're in Draco, we can't skip Nu (ν) and
Mu (μ) Draconis. They're two double stars in Draco's
head, and they provide two completely different
viewing experiences. Nu Draconis, also known as
Kuma, is a wide, even double of two 4.9-magnitude stars separated by an easy 63″. You can split
it in binoculars if you hold them steady enough.
The two components are so evenly matched that
in a telescope they look like the headlights of an
approaching car.
Mu Draconis is another perfectly matched
pair, with both components glowing at 5.7 magnitude, but at a much closer 2.3″ separation. This is a
medium-tough split, but well worth the effort, especially after looking at Nu's easy divide. It looks like the
same pair of headlights, only much farther away.
Fun fact: Mu Draconis's common name is Arrakis, which
Frank Herbert thought was cool enough to name his desert
planet in his groundbreaking science ﬁction novel, Dune.
From Arrakis, a quick
hyperspace jump through
pp NGC 6826 The Blinking
Draco's head takes you into
Planetary Nebula is one of
the upper wing of Cygnus, the
the night sky's few interactive
Swan. About where the pinion
objects. FOV = 50′
feathers would attach you'll
p DENSE SWARM M15 is one
ﬁnd NGC 6826, the Blinking
of the tightest globular clusters
Planetary Nebula. The Blinkin the galaxy. FOV = 20′
ing Planetary is even smaller
than the Cat's Eye, so you'll
u SPEEDY STAR 61 Cygni
moves so quickly relative to
need some magniﬁcation
background stars that you
here, but I include it because
can watch its position change
it's one of the best interactive
from year to year. Component
objects in the night sky. How
A is upper right, B lower left.
can something 5,200 lightFOV = 20′
years away interact with you?

TYC 3168-590-1

Sky and Telescope - October 2018

Table of Contents for the Digital Edition of Sky and Telescope - October 2018