Sky and Telescope - September 2018 - 67

u YOU NEVER KNOW NGC 7293,
more commonly known as the Helix
Nebula, is big and very, very dim
- but that doesn't mean you
shouldn't look for it! At first glance,
it may seem like nothing more than
a subtle brightening, but adding
a light-pollution filter to your eyepiece can pull out its circular shape
and possibly some of its wispiness.

like a backyard no-no. Not only
is it a nebula, it's a big nebula. The
Helix is 15.3′ × 12.0′ - most planetary
nebulae are less than 1.0′ in size. While it's
relatively bright at magnitude 7.3, its light should be considerably spread out due to the nebula's substantial size.
For years, I never tried to observe the Helix from the backyard, being content to view it from dark sites where it put on
a good show in my 6-inch refractor. One night, however, I
was in the backyard with the 6-inch and on a whim decided
to have a look for the Helix.
I put my eye to the eyepiece without any expectations.
Surprise! It wasn't bright, but the Helix was there. Adding
an LPR ﬁlter to the ocular improved the view considerably. I
could now see the Helix's ring shape. The darker center can
occasionally be difﬁcult even from country skies. Although I
couldn't see any of the spiraling loops of nebulosity that give
the Helix its name, I was thrilled with what I was seeing. In
amateur astronomy, never assume. Try anyway.
And so, we come to the end of tonight's sky tour. There's
much more to the autumn backyard sky than just the marvels we've admired here. For instance, we didn't visit any of

the multitudinous galaxies lurking in Pegasus. Many of those
dim sprites are visible from the suburbs, but nevertheless,
they're for another backyard evening. It's now time to take
our faithful telescope inside and ruminate on the wonders we
did see in our suburban night sky.

¢ While he can still be found at star parties, Contributing Editor and retired engineer ROD MOLLISE now enjoys observing
from his suburban backyard. While the skies aren't perfect, he
can cruise the deep sky every clear night.

Suburban Deep-Sky Sights
NGC 7293 SK E TCH: JEREM Y PERE Z; NGC 7293 PHOTO: N ASA / NOAO / ESA /
HUBBLE HELIX NEBUL A TE A M / M. MEIX NER (STSCI) / T. A . RECTOR (NOAO)

Object
M56

Type

Constellation

Mag(v)

Size

Dec.

Globular cluster

Lyra

8.3

5.0′

19h 16.6m

+30° 11′

01h

09.4m

+35° 43′

NGC 404

Lenticular galaxy

Andromeda

10.3

3.5 × 3.5′

M110

Elliptical galaxy

Andromeda

8.5

17.8′ × 9.8′

00h 40.4m

+41° 41′

Globular cluster

Aquarius

6.5

16.0′

21h 33.5m

-00° 49′

53.5m

-12° 32′

M72

Globular cluster

Aquarius

9.2

5.9′

20h

M73

Open cluster

Aquarius

8.9

2.8′

20h 58.9m

-12° 38′

NGC 1055

Spiral galaxy

Cetus

10.5

6.2′ × 2.9′

02h 41.8m

+00° 27′

34.5m

+22° 01′
-20° 50′

M1
NGC 7293

Supernova remnant

Taurus

8.4

8.0′ × 10.0′

05h

Planetary nebula

Aquarius

7.3

15.3′ × 12.0′

22h 29.6m

Angular sizes and separations are from recent catalogs. Visually, an object's size is often smaller than the cataloged value and varies according to the aperture
and magnification of the viewing instrument. Right ascension and declination are for equinox 2000.0.

sk yandtelescope.com * S E P TE M B E R 2 018

http://www.skyandtelescope.com

Sky and Telescope - September 2018

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