Last Saturday night (November 18th), I took a chance on mixed weather
prospects and headed south to the Willow Springs property of Bob
Ayers, meeting Mark Wagner, Ray Cash and Charlie Wicks. Mark and Ray
had just preceded me when I arrived and we were pleased to see a bank
of clouds far to the north, but clear dark-blue skies overhead.
Conditions were nearly ideal (very dark and very steady) for the
first three and half hours until 10:00 PM and then clouds filtered
over for the next two hours. Bob decided to pack it in and head back
home and that seemed to appease the weather gods as we had perfectly
clear weather again until 3:30 when we were exhausted.
It was good galaxy hunting conditions as stars were pinpoints at 280x
and the background quite contrasty, making it easy to pick out tiny
galaxies within clusters. So, that's mainly where I spent my time.
Splashed across the fall skies is a river of galaxies beginning in
Pisces at the NGC 383 group and flowing towards the east-northeast.
This river contains a number of congested spots where groups and rich
clusters of galaxies huddle together. A few degrees to the east of
the NGC 383 group is another dense clump of galaxies that forms the
NGC 507 cluster and over the border into Andromeda we find the NGC
536 clan. Continuing further east-northeast, several rich clusters
mark the way including Abell Galaxy Cluster (AGC) 262 , AGC 347, NGC
1129 cluster and AGC 426 (Perseus Cluster). At a distance of nearly
300 million light years, the Pisces-Perseus supercluster is one of
the largest known structures in the universe and stretches across
nearly 40° of the fall skies. And it would likely continue further
if it did not become lost (at least at optical wavelengths) behind
the veil of dust in the Milky Way (more at the end).
I started off the evening with the Pisces Group, located at the west
end of the Pisces-Perseus supercluster. This group contains 5
relatively bright NGC galaxies in a striking chain and a school of
fainter galaxies swimming nearby. From south to north here are the
main players --
NGC 384: moderately bright, fairly small, irregularly round,
0.6'x0.5', fairly well concentrated with a small bright core. At the
south end of the Pisces Group with N385 1.7' N.
NGC 385: moderately bright, fairly small, round, 1.0' diameter,
strong concentration with a bright 20" core. Appears slightly larger
and brighter than nearby N384.
NGC 383: fairly bright, moderately large, irregularly round, 1.3'
diameter, broadly concentrated to a bright core which increases to a
6" nucleus. Forms an interacting pair with N382 30" S of center.
This galaxy is the brightest and largest member of the Pisces Group
and is surrounded by 10 galaxies within 8'!
NGC 380: moderately bright, fairly small, round, 40" diameter,
sharply concentrated with a very small, very bright core. Forms a
2.2' pair with N379 and 4.5' NNW of N383.
NGC 379: moderately bright, fairly small, elongated 3:2 N-S,
0.8'x0.5', broad concentration with a slightly brighter core. Forms
a similar pair with N380. This galaxy is at the north end of the
"Pisces Group" centered on N383.
In the same 225x field, I also found NGCs 373, 375, 382, 386, 387,
388 for a total of 9 NGC galaxies. The faintest of these are NGC 373
and 387 with catalogued B magnitudes of 15.9 and 16.5 attesting to
the dark skies at Willow Springs.
The rich galaxy cluster, Abell 119, can be found by panning 50' east
of the 4.8-magnitude star 20 Ceti. This cluster resides a mind-
boggling 600 million light years from home and is one of the most
distant clusters easily accessible in an 18-inch scope. Back in the
fall of 1988 from the Sierra foothills (Fiddletown), I located 6
members in my 17.5-inch. As even the brightest members are not
catalogued in the NGC or IC, I thought I was doing pretty well, but
from Willow Springs (and an extra half-inch of aperture!), a dozen
galaxies were identified. Here are my notes on the trio of brighter
galaxies in the core of the cluster --
UGC 579: this cD galaxy (a class of huge ellipticals that grow
through cannibalizing smaller cluster members) is the brightest
member of AGC 119. At 220x it appeared moderately bright, fairly
small, round, 0.8' diameter, broad concentration with a slightly
brighter core. In the core of the cluster is a nest of faint
galaxies surrounding UGC 579 and UGC 583 (located 2.4' ESE).
UGC 583: the second brightest member of AGC 119 appeared fairly
faint, small, round, 0.4' diameter, small bright core, fairly high
surface brightness. Located 2.4' ESE of UGC 579. Forms a double
system with CGCG 384-37 at the south edge. The two brightest members
in the core form the base of an isosceles triangle with a mag 10.5
star 3.5' S at the vertex.
MCG +00-03-033: faint, very small, elongated 3:2 NW-SE, 0.3'x0.2',
contains a quasi-stellar brighter nucleus with direct vision. Forms
the northern vertex of an isosceles triangle (with sides ~3') with
UGC 579 and 583, the two brightest members of AGC 119.
Next group up was the NGC 1016 cluster, located 100' southwest of the
challenging double star, Gamma Ceti, a yellow/pale blue pair of mag
3.5/6.5 stars at 2.3". The cluster contains 9 NGC galaxies (993,
1004, 1007, 1008, 1009, 1016, 1019, 1020, 1021) that were discovered
by Albert Marth, using a 48-inch f/9.4 fork-mounted reflector (that's
right) from Malta and Jean Marie Edouard Stephan (Stephan's Quintet
fame) using the Foucalt 31.5-inch silvered glass reflector of the
Marseilles Observatory. This cluster was missed entirely by both
William and John Herschel which is surprising as there are several
reasonably bright galaxies. Here are a few of the better members --
NGC 1016: fairly bright, moderately large, round, 1.5' diameter.
Contains a bright 20" core that increases to the center. Located 8'
SE of a mag 9.6 star. Brightest and largest member of the cluster.
NGC 1004: fairly faint, fairly small, slightly elongated, 0.5'x0.4',
weak concentration. A mag 12 star is attached at the W edge of the
halo. Located 13' SW of N1016 on the west side of the cluster.
NGC 1019: fairly faint, moderately large, irregularly round,
1.0'x0.8', low surface brightness. Located 13' SSE of N1016. CGCG
388-080 lies 3.7' N.
IC 241: fairly faint, small, low surface brightness halo surrounding
a very small brighter core. Located 8' N of a mag 9.5 star and 14'
NW of N1016 in a cluster.
Next I returned to the Pisces-Perseus supercluster, but this time
explored the NGC 1129 cluster, the last stop before the Perseus
cluster near the apparent eastern terminus of this meandering river
of galaxies. William Herschel found the brightest member, NGC 1129 -
a massive cD galaxy, but missed its dim companions. Two additional
members, NGC 1130 and 1131 were found by Lord Rosse, using his 72-
inch speculum reflector at Birr Castle in Ireland but surprisingly he
missed a brighter galaxy, MCG +07-07-008, that is nearby. In
addition to these 4 galaxies, I picked up 4 additional members for a
total of 8. Here's the lowdown on the main players --
NGC 1129: this giant cD galaxy is the brightest in the nearby, X-ray
bright cluster WBL 88 = AWM 7 (z = 0.017). Several faint galaxies lie
within a few arcminutes including N1130 1.7' NNW and N1131 1.8' SE.
A very faint companion (MCG +07-07-003) is embedded at the SW edge of
the halo and appears like a short spike jutting out towards the SW.
NGC 1130: faint, very small, elongated ~2:1 SSW-NNE, 0.4'x0.2'. A
mag 14 star is attached at the S end. Located in the core of the
N1129 cluster just 1.7' NNW of N1129.
NGC 1131: faint, very small, round, 20" diameter, weak even
concentration. Located 1.7'' SE of N1129 in the core of the
cluster. Brighter MCG +07-07-008 lies 2.7' SE!
MCG +07-07-008: this member of the N1129 group (WBL 88) appeared
fairly faint, fairly small, round, 40" diameter. Surprisingly Lord
Rosse discovered much fainter N1130 and N1131 in his observation of
N1129, but didn't mention this galaxy which is located just 4.4' SE
of N1129.
Finally, I ended the evening at Abell Galaxy Cluster 569 in Lynx.
There is evidence (see http://tinyurl.com/wox97) that the Pisces-
Perseus crosses the Milky Way in Perseus and re-emerges from the veil
of dust at AGC 569. If this cluster is connected with the main
supercluster, the filament would extend a total length of 500 million
light years!
This cluster is dominated by two members, NGC 2329 (discovered by
William Herschel) and UGC 3696 and I logged 7 members in total. I'm
surprised the Herschels missed the latter galaxy as it is relatively
bright (just a couple of tenths of a magnitude fainter than NGC 2329
and too close to miss. Anyways, here's how I recorded the 3
brightest members --
NGC 2329: moderately bright, moderately large, oval 4:3 N-S,
1.2'x0.9', contains a large, brighter core. This galaxy and UGC
3696, located 2.8' NE, are the brightest member of AGC 569. I found
7 members of the cluster at 280x.
UGC 3696: fairly faint, oval 3:2 WSW-ENE, gradually increases to a
small bright core. Forms the western vertex of an isosceles triangle
with two mag 11-12 stars 1.7' NNE and 1.7' SW. Located 2.8' NE of
N2329 in the core of AGC 569. It's strange that neither William or
John Herschel, who both observed N2329, failed to pick up this
relatively bright galaxy as it is only slightly fainter than N2329.
MCG +08-13-061: this relatively bright MCG galaxy in Abell Galaxy
Cluster 569 appeared fairly faint, fairly small, slightly elongated,
0.6'x0.5', small bright core. Located 3.5' SE of a mag 9.3 star.
During the evening one of Bob's neighbors stopped by to chat about
astronomy. While driving out, I stopped at his gate and just stared
at his 33" f/5 which was still set up in his backyard from the
previous night. Looking forward to another visit.
Steve Gottlieb
-- What TAC Is About. http://www.observers.org/Join.shtml Webcam, DSLR, CCD Imaging use NorCal AI. http://tech.groups.yahoo.com/group/norcal_ai/ Designing and improving TAC's website. http://tech.groups.yahoo.com/group/tac-ops/ Sub-scribe or Unsub-scribe from TAC http://seds.org/mailman/listinfo/sf-bay-tacReceived on Mon Nov 27 19:07:19 2006