Off the Beaten Path with Steve Gottlieb:
Autumn Deep Sky Challenges
Planetary Nebula - Abell 72 20 50.1, +13 33
This relatively easy Abell planetary should be visible in a 10"-12" scope. At
100x and OIII filter appeared fairly faint, large, 2' diameter. Has an
irregular shape without crisp edges. Here's the fun part -- mag 8.1 SAO
106544 is just off the the WSW edge 1.8' from the center! Also mag 8.9 SAO
106544 lies 3.8' NNE and two mag 11 stars and a mag 13 star are just off
the E and SE edges. A mag 13 star superimposed in the center is probably
not the central star. Also viewed unfiltered at 220x although best view is
at low power.
Bipolar reflection nebula or protoplanetary nebulae - the "Egg" nebula 21 02 18.8, +36 41 41
My best view of the Egg Nebula was at 280x although this object was
surprisingly small and on first glance at lower power appeared as a 10"-15"
unequal double star. The orientation of the pair is SSW-NNE with the
brighter mag 12 component on the NNE side, ~15" diameter. The fainter mag
13.5 object is clearly nonstellar at this power, although only ~10" in
size. The components appear encased in small faint halo oriented SSW-NNE.
Globular Cluster - Palomar 12 21 46 39, -21 15.1
This relatively easy Palomar globular is situated close NNW of a
distinctive trio of mag 12 stars. The southern two stars are well-matched
pair at ~15". The globular appeared an irregular 3' glow at 220x with
ill-defined edges. With attention, three very faint mag 15 stars could be
resolved over the faint background glow.
HII region - the "Cave" nebula = Sh 2-155 22 56 43.2, +62 37 04
A controversial object, Patrick Moore undeservingly dignified this faint
HII region in his "Caldwell Catalogue". You have to serious question
whether he ever viewed this difficult object! It was best seen at 100x as
a large, diffuse glow mostly surrounding mag 8.5 SAO 20334 and extending
north towards mag 7.6 SAO 20335 located 7' due N. I tried using OIII and
H-Beta filters but neither provided a noticeably improved contrast. The
only structure visible was a very small knot less than 3' ENE of the mag
8.5 star. At 220x this locally brighter spot was clearly seen as a faint
1' roundish glow. This may be an interesting object photographically but visually it is a challenge just to view.
Galaxy Pair - The "Taffy" Galaxies (UGC 12914 and UGC 12915) 00 01 38.2,
+23 29 05
A close pair of elongated galaxies in roughly the same orientation. They
were dubbed the "Taffy" galaxies due to emission stretched between the
objects. The brighter member UGC 12914 appeared as a faint, moderately large edge-on
4:1 NNW-SSE, 2.0'x0.5'. A mag 12.5-13 star is at the SE tip 1.6' from the
center. UGC 12915 lies just 1' NE and is elongated elongated 3:1 NW-SE,
1.2'x0.4', with an even surface brightness.
Galaxy Group - The NGC 3 group 00 07 16.8, +08 18 06
Many observers have viewed NGC 1 and NGC 2 which form a close pair -- and
whose main claim to fame are their top position in the NGC (in 1860
coordinates). But the little-known NGC 3 group holds the distinction of
containing 5 galaxies both near the beginning and end of the NGC!
The brightest member, NGC 3, appeared fairly faint, slightly elongated,
containing a bright core. A mag 11.5 star is 1' WSW. If you can locate
NGC 3, see how many of the neighbors you can detect. Nearby are NGC 7838
6.3' NW, NGC 7837 6.9' NW, N7835 10' NW, and NGC 4 5' NNE. And the last
one will most certainly be a torture! (16th magnitude)
Superthin edge-on - NGC 100 00 24 02.6, +16 29 10
With listed dimensions of 5.5'x0.7' this one qualified for the "Flat Galaxy
Catalogue". I recorded it as very faint, elongated 6:1 WSW-ENE, 2.0'x0.3',
This planetary was discovered in 1984 by rescanning the original Palomar
Sky Survey plates *visually* looking for missed large low surface
brightness objects! This is a big one -- 5'x3' -- but tough!
In my 17.5" I used 105x and an OIII filter to identify a very faint glow
surrounded by a group of faint stars. Can just hold steadily with averted
vision. Back in 1986 (soon after reading the discovery paper) I glimpsed
this planetary with my 13' (barely).