I will top post here so that if anyone is interested they can just click
down to read this fine post.
I am very disappointed that no one has responded to your observing night
post. Perhaps the lack of responses reflects the degeneration the quality
of posting on this forum. The level of static to good posts like this one
is getting so high on this group that I seldom spend much time here anymore.
I followed most of your reported activities last Thursday night at the Dark
Sky Party near Springfield Illinois, sponsored by the Sangamon Astronomical
Society, with my 10 inch dob. It was a lot of fun to follow your
adventures for my observing session.
I had to go over to a neighbors 17 inch to see some of the objects though.
Please keep posting, a few people that read this group are still interested
in visual astronomy.
Jule J. DuBois
"David Knisely" wrote in message
...
DS090904 RECENT OBSERVATIONS
by David Knisely
DATE: September 9th, 2004, 0130 to 0650 hrs UTC.
LOCATION: Rockford Lake, Nebraska 40.227N, 96.580W, 1400 ft (427m) elev.
INSTRUMENTS: NexStar 9.25" Schmidt-Cassegrain, 78x, 98x, 168x, 297x, 479x.
SkyView Pro 100mm f/6 refractor: 20x, 25x, 43x, 63x, 76x, 122x, 190x.
CONDITIONS: Clear, Temp. 65F (18C), wind calm.
UNAIDED-EYE ZENITH LIMITING MAGNITUDE: 6.6
SEEING (above 45 deg. altitude): 1" arc (Antoniadi II).
OBJECTS OBSERVED: Izar (Epsilon Boo), M8, M20, M22, M24, M17, M16, M11,
M23,
M39, M29, M57, M74, M76, NGC 246, NGC 253, NGC 281, NGC 869-884, NGC 891,
NGC 6781, NGC 6826, NGC 6888, NGC 6960-79-92, NGC 7000, NGC 7009, NGC
7331,
NGC 7335, NGC 7340, Stephan's Quintet (NGC's 7317-18A/B-19-20) NGC 7293,
NGC 7789, NGC 7814, IC 1318, IC 1613, Kemble's Cascade (Cam), various
NexStar "Tour" asterisms.
OBSERVATIONS: I usually see a dark blue sunset sky as the "call" to pull
all
my stuff together and get out to my local dark sky site, but the previous
night, I just hadn't had the energy. Tonight, however, I vowed it would
be
different. I had a lot to load, as I wanted to test out the 25 foot
RS-232
cable that I had purchased to allow my laptop to sit in the back of the
minivan controlling my NexStar 9.25GPS sitting at a comfortable distance
away. The laptop's screen, even with the Rubylith over it, was
distracting
when placed under the scope, so I wanted the laptop as far away as
possible.
Thus, this observing session was mainly to be a fun revisiting of objects
I
had long ago observed, as well as an equipment test. I had to load the
following items into my van:
1: the NexStar 9.25GPS and its tripod
2: the laptop
3: two 12V Battery power supplies (18 amp-hr one for the NexStar and a 21
amp-hr one with inverter for the laptop)
4: my Orion Deluxe adjustable observing chair
5: my "portable library" (carry-on luggage carrying Sky Atlas 2000.0 and
Uranometria 2000.0, three guidebooks, plus my two logbooks)
6: two accessory storage bags (one for the NexStar's bolts and cables, and
one for the SkyView Pro 100's battery pack, controller, and Rigel
Quickfinder)
7: my eyepiece case
8: my rich-field Orion SkyView Pro 100 refractor!
Needless to say, it took nearly an hour to get everything I thought I
might
need properly loaded, and about 18 minutes later, I was out above the
shore
of Rockford lake looking up at a beautifully clear and rapidly darkening
sky.
The first thing out was the NexStar, and after firing it up, I stood in
horror looking at a scope which had turning motors but no motion of the
mount! Then, I realized that the scope's azimuth clutch was still
unlocked
from transport, so with one flick of the lever, the scope began to move
properly (whew!). I then set up the SkyView Pro 100 on its German
equatorial
mount and started with a quick look at Izar. I had recalled a thread on
Cloudynights about a claim of it being "split" with a 60mm aperture, so I
kicked up the power to around 190x. Sure enough, the 100 split the double
with ease, although the companion was not all that bright. I stopped the
scope down to 53mm, and the companion vanished except for a brightening
roughly on top of the primary's first diffraction ring.
I had intended to then get the laptop fired up and controlling the
NexStar, but the Milky Way was so inviting that I let the NexStar just sit
and spent most of the first hour playing with my big refractor. With the
30mm WideScan eyepiece, a 4 degree field of view at only 20x is just plain
heavenly, especially in Sagittarius. The main starcloud showed huge veins
of
dark nebulosity and lanes that were glistening with an almost uncountable
number of faint stars. I could see a number of the smaller globulars as
small fuzzy spots burried in the glow of the starcloud.
Moving north, I entered the void centered on the Lagoon and Trifid
nebulae. In went the UHC filter, and these two objects just looked huge
compared with what I often usually see without the filter. M8 in
particular
was quite long, something over a degree in length and nearly one in width.
It had a number of very faint outer tendrils that made it look a little
different than I often see it. The detail around and inside of it was
faint
but almost photographic. M20 showed both the emission Trifid form and the
patch of reflection nebulosity to its north. With the 24mm Panoptic (25x,
2.6 degree field), the three lanes were just barely visible but the detail
was not all that bright. I went over to the NexStar to see what it would
show. The three irregular dark lanes were easy to see at 78x, along with
plenty of other light and dark structure.
I moved the NexStar back down to M8 and was rewarded with a view that
again
resembles at least some photographs. The open cluster in the bright arc
(NGC 6530) was almost burried in the glow, with the usually dark lane-like
feature between it and the main "ball" of the nebula also glowing. The
glow
of the outer nebulosity virtually filled the 1 degree field of the 30mm
eyepiece, with faint tentrils of nebulosity visible. I put in the OIII
filter, and some of the outer stuff dimmed or vanished, but the dark
detail
in the main part of the nebula became much sharper and easier to see.
With
the higher contrast, a number of the small dark patches shown on many
images
were visible, along with two narrow dim dark lane-line strips inside the
"dividing lane" between the "ball" and the star cluster.
Back at the refractor, I noted the glow of the "non-existant" nebula
plotted on Sky Atlas 2000.0 as NGC 6526 just north of M8. It is really
just
a star cloud, as at 78x power in the NexStar, the stars in it begin to
show
up fairly easily. Farther north in the 100mm f/6 was beautiful M24, the
Small Sagittarius Star Cloud. This glowing elongated mass of stars is not
only stunning, but is flanked by a few large dark almost circular dark
nebulae. In fact, for some reason, these dark nebulae seemed to be darker
with the UHC filter being used than without. I took a side trip to M22,
and
even with the refractor, this big globular showed many stars at high
power.
It also looked distinctly oval, an appearance which was comfirmed by the
view
through the NexStar 9.25" SCT at 98x. The view in the NexStar was, of
course
vastly better than in the refractor, as 298x resolved it well, revealing
many hundreds of stars.
I moved on north to M17, and again, in the 100mm refractor with the
UHC
filter, the object looked larger and more interesting than I remember. In
particular, the normal hook or swan-like appearance was augmented by a
diffuse outer loop of neblosity which arcs away to the east and then back
again towards the north. I have seen the northern loop many times in my
10
inch, but at this low power and wide field, it seemed wider and more
prominent that usual. I had to have at least a brief look with the SCT,
and
the usual large swan-like form almost looked like the inverted bow of a
WWI
battleship. The OIII filter showed the dark detail quite easily, although
again, the outer loop looked better in the UHC filter. M16 was also quite
easy in the refractor at only 20x, although again, the UHC made it look
considerably larger and more distinct. The nebula itself looked like a
fat
short mushroom, but in the NexStar, the object shows some interesting
light
and dark detail, especially in the form of the very dark inclusion into
the
northern side of the nebula. With the OIII filter at 98x, I could
occasionally catch just a hint of the narrow dark strip of the "pillars of
Creation" which juts from near the center of the cluster towards the
southeast.
With the hand controller of the NexStar now "in hand", I decided to
slew
to some targets in its database, as I still had not set up the laptop. I
hit
M11, and its form was quite stunning. In fact, with the mirrored star
diagonal, the outer stars showed dark inclusions, making it look a bit
like a
"stellarized" line drawing of the Hubble Space Telescope! Two inclusions
made for spaces that outlined the edges of the solar panels and the "gaps
between the panels and the main tube assembly. I had never really noticed
this before, but it does take a little imagination (and a little aperture)
to
get this cluster to appear this way. I also stopped at the large (1.8'
arc)
planetary nebula NGC 6781 in Aquila. It was visible without a filter, but
the OIII really made it stand out well as a dim circular disk with a
darker
middle as if it were almost annular. One edge of the disk looked a bit
darker than the other, and the star field around the object was fairly
rich.
With planetaries in mind, I sent the NexStar to M57. At 78x, the ring was
beautifully shown, and with the UHC filter, hints of the faint patches of
the
outer shell on the edges of the main ring were seen. I kicked things up
to
297x, but saw no hint of the central star, so I went even higher. At
479x,
one look in showed the star shining briefly, but just as quickly, it
vanished, never to be seen again that night! Seeing had just taken a turn
for the worse, so the high power image stability needed to keep that 15th
magnitude star from blending into the glowing background just wasn't there
anymore!
Frustrated by this, I went back to my 100mm f/6 refractor. With
Cygnus
high in the sky, I decided that it was time to look for the Veil. I put
the
OIII filter on the 30mm WideScan III and put the scope on 52 Cygni. BANG!
I
was just blown off my chair! Here in the 4 degree field were *both* sides
of
the Veil showing up very clearly, along with the faint triangular patch
between them (Pickering's Triangle, NGC 6979). The faint "claws" on the
south end of NGC 6960 showed up surprisingly well in that 4 inch scope,
and
even some of the filamentary structure of the other half (NGC 6992) was
visible. I ordered the NexStar to go to the Veil, and not surprisingly,
it
went to the curved arc of NGC 6992, rather than the section that goes
through
52 Cygni. The NexStar showed the fine filaments in the Veil quite well,
although in a way, I kind of preferred the view of both sides of the
nebula
in the same field of view of the refractor.
With this one under my belt, I could see the faint glow of the North
America Nebula (NGC 7000) with my unaided eye, so I put the 24mm Panoptic
and
the OIII in the 100mm refractor and off I went. I accidently hit the
finderscope with the bill of my cap, so when I looked into the scope, all
I
saw was a rich field of faint stars. I started roving around and
suddenly,
the stars started to thin out abruptly. I was in some sort of dark nebula
which was very well defined on its edges. I moved the scope a little more
to
the northwest and WHAM!, there it was!!! I was simply stunned again.
Here
was dim but *obvious* glowing shape that, although it was backwards,
clearly
showed the form of the North American continent filling the 2.6 degree
field
of the 24mm Pan. The "Gulf of Mexico" portion stood out against the glow
of
the Mexico band, and even the projection of "Florida" was easy to see.
The
little dark inclusion (B352) which is sometimes referred to as "Hudson
Bay"
was also visible on the nebula's northern edge. I put in the UHC filter,
and
although the nebula was a bit brighter and stillfairly clear, I liked the
contrast provided by the OIII filter better for this object. I could also
see the fainter patchy form of the "Pelican" Nebula (IC 5067-70) just to
the
southwest of NGC 7000. I have seen these objects many times before, but
this
night, they were a lot better looking than I expected!
I put the 30mm WideScan III and the UHC filter in and centered the
100mm
scope on Gamma Cygni. There is a lot of faint diffuse nebulosity around
that
star, and the 100mm scope did show it in the form of some huge diffuse
patches (IC 1318) in various places around the star. They were quite dim
and
rather irregular in shape, so they aren't exactly spectacular. Well
southwest of Gamma was a very small and dim arc-like patch which I
recognized
(barely) as the NGC 6888 (also known as "the Crescent Nebula"). Seeing it
made me put the OIII filter in the 30mm and put the combination into the
NexStar 9.25" SCT to see what could be seen. The dim arc was now huge,
and
was the brightest portion of a large very faint oval nebula that has a few
7th and 8th magnitude stars on it. I could see some vague dark patches in
the interior with the arc being located on the northern edge of this large
but faint oval. I also went to "the Blinking Planetary" (NGC 6826).
This
object really looked nice at 98x, showing a bright central star encased in
very slightly oval disk of bluish-green light with very definite edges.
The
edges off the ends of the oval appeared just a tad more diffuse than the
other two edges.
I then decided to see what the "Tour" in the NexStar's database
would
do, as I have never used this feature. It apparently picks a number of
"highlight" objects from its database that are above the horizon and (in
no
particular order) takes you to them. A few ended up just being double
stars
that I had little interest in (some were *very* wide and are better finder
doubles), and many of the rest were the usual "showpiece" objects I had
been
observing earlier. In a number of cases, I questioned the existance of
some
of these "objects", as they are given names like "the "M" Cluster" (a
group
of six widely-spaced stars in the boonies of Draco) or some such name (no
ID
on many of them other than the name). I was questioning whether this
"tour"
was at all realistic when the name, "Kemble's Cascade" appeared in the
hand
controller's window. I have heard of this one, but have never seen it, so
I
selected it and the scope dutifully slewed to it. One look in my 9x50
finder
surprised me. This is one MARVELOUS group of stars which is an ideal
target
for *low* power spotting scopes or finders. It is in Camelopardalis
(R.A. 3h 58.5m, Dec. +62 deg. 55') and appears as an irregular line of
magnitude 7 to 11 stars over two degrees long with a split towards its
southeastern end which contains the open cluster NGC 1502. The whole
thing
reminded me a bit of the lights in the window of an airliner, or maybe
some
sort of celestial "divining rod". In any case, it was definitely worth
the
slew!
By now, Andromeda was getting higher, so it was time to look at it
with
both my telescopes. M31 was very nice in the 100mm f/6 refractor at only
20x, showing not only the brighter core but hints of the spiral arms near
each end. I found that the view with the 24mm Panoptic was better, as
detail
started to come out that I had missed at the lower power. A few dim
patches
were noted in the southwestern section of the galaxy, and the gentle curve
of the northeastern end was also visible, but what surprised me was the
abrupt appearance of the first dark lane! I could just begin to see the
arm which flanks it along the galaxy's western side, something I sometimes
have trouble with even in an 8 inch. Both M32 and NGC 205 (M110) were
also
easy to see, with M32 showing its star-like center at 43x. I then sent
the
NexStar 9.25GPS over to M31. Again, the view was narrow in field but
still
quite interesting. The dark lane structure around the arm west of the
galaxy's core region was quite easy to see, and for once, I got bit of a
glow west of the *second* dark lane! I slewed the scope around to pick up
the large star cloud (NGC 206) in the southwestern arm, and it was fairly
easy to see, along with the much larger but more diffuse patches that make
up that part of the arm. The dim diffuse arc of the northeastern arm was
also seen with a few vague brightness variations along it. I also took a
long look at M33 using both scopes. In the 100mm f/6, the galaxy was
quite
easy and looked somewhat mottled with a brighter core. Hints of one arm
segment were visible, but the overall spiral structure remained elusive.
In
the NexStar, the spiral structure was masked somewhat by the huge number
of
faint patches and detail which nearly filled the field of view. These
patches are superimposed on a larger fainter slightly mottled oval halo
which
extended a little beyond the field of view. Two arms were tracable, but a
larger fragment of what might be a third arm southwest of the core tends
to
make the southern arm seem less distinct and harder to notice especially
at
lower powers.
I sent the NexStar back to its "tour" to the edge-on spiral galaxy
NGC 891. At 78x, the galaxy appeared as a ghostly cigar-shaped area of
light
which was a bit irregular along the edges and a little fatter towards the
middle. I could see hints of the narrow dark lane down the length of the
galaxy at 78x, but it was better seen at 98x, although it has looked
better
at other times. Just for fun, I moved the 100mm f/6 to the area of NGC
891,
and sure enough, it was just barely visible as a small but very dim sliver
of
light. While in the area, I slewed the NexStar to M76. This little
peanut-
shaped planetary showed a little more of its stuff at moderate power, as
with
the OIII filter faint patches of light were seen off of the two sides.
This
sometimes gives the object the name, "the Butterfly Nebula".
I started using the Go-To capability of the NexStar to do some
"rapid-fire"
observations of a large number of objects. When trying for a member of
the
local group (the irregular galaxy IC 1316), I hooked up the laptop and
discovered that if the computer doesn't have its date and time matching
that
reality, it will refuse to send the scope to an object it thinks is
*below*
the horizon. That had happened, as the computer's date and time had to be
reset to UT and my location back to Rockford Lake instead of NSP's Merritt
Reservoir. I also discovered that you shouldn't try to realign the
NexStar's
Go-To system while connected to the laptop, as it will slew to the next
object and then promptly lock things up! After a few minutes of
frustration
with the laptop, all was well, and I found the galaxy (barely, as it is
very
very dim but rather big). I slewed to the galaxy M74 just for fun, and
noticed that at 98x, there was a lot more mottling in its outer haze than
I
remember. I hit the Double Cluster, but again, the temptation of the
100mm
f/6 refractor was too much to resist, so I had to look at this area with
the
other scope as well. At 25x, the faint outer halos of faint stars which
surrounds the cores of each cluster were visible, although they looked a
bit
more distinct at 43x. I hit NGC 7331, which in the NexStar looked a lot
like
M31 does in my finderscopes, with hints of patchyness in the outer haze.
It
shows a marked dropoff in brightness along the western side, and showed a
couple of very faint companion galaxies next to it. Of course, one
doesn't
visit this galaxy without also taking a look at nearby Stephan's Quintet.
At 98x, I could glimse 4 of its members, but none were very bright or
distinct.
I took a look at the Saturn Nebula in Aquarius at 298x, and could
just
barely see the two ansae off the ends of the nebula's bluish-green main
oval.
The main oval of this bright planetary nebula surprisingly showed a little
detail of its own, with a oval ring-like inner segment imbedded in a more
diffuse outer haze. The Helix (NGC 7293) also fell easily to the NexStar,
although I liked the view I got of it with the 100mm f/6 refractor and the
OIII filter as well (big fuzzy donut). I tried to see the narrow dark
lane
in the edge-on spiral NGC 7814 in Pegasus, but didn't get more than just a
hint of it. I hit a few more targets before settling on the bright spiral
NGC 253 in Sculptor. It at first seemed loaded with fine detail, but as
the
minutes went on, it seemed that the contrast was dropping. I looked at
the
SCT's corrector plate and noted that it was clear, but as I turned to the
northeast, I saw the reason for the loss of contrast. The fat crescent
moon
was rising above the trees, so I figured it was time to call it a night.
Clear skies to you.
--
David W. Knisely
Prairie Astronomy Club: http://www.prairieastronomyclub.org
Hyde Memorial Observatory: http://www.hydeobservatory.info/
**********************************************
* Attend the 11th Annual NEBRASKA STAR PARTY *
* July 18-23, 2004, Merritt Reservoir *
* http://www.NebraskaStarParty.org *
**********************************************
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