Fun at Fremont Peak

[Jay Reynolds Freeman]

I was at Fremont Peak State Park, near San Juan Bautista,
California, on the night of 9-10 November, 1996. The night began
inauspiciously, with moderate cloud cover after a rather overcast day,
but the sky cleared as the evening wore on. There was no fog below to
turn off the lights of cities and towns, but clear sky made for high
transparency and good viewing. I was set up with my 6-inch f/10 Intes
Maksutov, mostly chasing down Messier objects in the winter sky.

Even though I had viewed it before with this instrument, I started
the evening with a low-magnification view of the Pleiades. I used my
old 55 mm multi-coated University Optics Plossl, an eyepiece that I
actually had not taken out of the box for a few years. The eye relief
is several inches -- almost too long, and that and a rather narrow
apparant field -- the design diameter of the Plossl's front lens would
more than fill the two-inch barrel -- had made me forget how good it
is. In any case, I was rewarded with the best view of the Pleiades
nebulosity I have ever encountered. I have seen the Merope nebula
many times before, but this was the first occasion on which I have
been willing to call it bright and obvious. There was lots more wisby
nebulosity in the cluster, too.

M42/43 was nice with the same eyepiece, and showed noticeable
variation in color -- bluish-green near the Trapezium, warmer tones at
the high-contrast boundaries of the "wings" of the nebula, and in M43.
I added magnification to look at details. M1 showed its rather
characteristic roast-chicken shape, and at 150x hinted of structure
within the plasma cloud.

I spent a lot of time looking at the Horsehead. Some folks were set
up with a 20-inch Dobson and a Lumicon H-Beta filter, and had an excellent
view of it. I had two filters -- an Orion UltraBlock and an old, old,
Celestron LPR filter, one of the lime-green ones that date from the era
when there was only one kind. I tried each of them on each of three
eyepieces, and also viewed unfiltered. I was able to hold the Horsehead
with averted vision in my 6-inch Intes at each of 27x, 38x, and 47x,
both unfiltered and with the old Celestron LPR, but I could not see it
at any of those magnifications with the UltraBlock. All nine combinations
of eyepiece and filter (or no filter) showed NGC 2023 and 2024, as well as
IC 435, easily. (NGC 2024 is sometimes called the "Flame Nebula" or --
more descriptively, I think -- the "Tank Tracks". It lies NE of zeta
Orionis. The other two are nebulae surrounding stars that lie S or SE of
zeta.)

The pieces de resistance for the night were dwarf galaxies. I had
had a nice session looking at the Sculptor Dwarf from this site a
month or two ago, mostly with other peoples' equipment, and was
anxious to try it with the Intes. I also had a new, rather
interesting, special dwarf galaxy filter, intended to put the lie to
the common misconception that no filter will help with galaxies, and
I was anxious to try it out.
At 27x, with the 55 mm Plossl, I had no problem chasing down the
Sculptor Dwarf again, though it helped greatly to know exactly what I
was looking for and exactly where it was. The little whizmo dwarf
galaxy filter seemed useful, too. Then I went looking for the Fornax
Dwarf, which is fainter than the Sculptor one, but smaller, hence of
similar surface brightness. Small size helps in another way, for the
Sculptor Dwarf is so large that at many magnifications it more than
fills the field -- one must swing the telescope from side to side to
detect it.
Anyhow, I found the Fornax Dwarf. I had actually seen part of it
once before -- there is an embedded globular cluster, part of this
galaxy and not merely a foreground object in our own, that is bright
enough for an NGC number. But it was neat to detect the pale glow
of the main system. The golly gosharootie dwarf galaxy filter seemed
to help with the Fornax Dwarf, too, though I did not need the filter
to see it.
About then Rich Neuschaefer came by. I was pleased to be able to
show him the Fornax Dwarf, and he, too, upon consideration agreed that
the supercalifragilisticexpialidocious dwarf galaxy filter gave a net
improvement in visibility. How neat to be on to something that the
LPR marketing mavens have missed!

Before I packed to go home, I continued the Messier survey with my
10x50 Orion UltraView binocular that I have described here before. There
were no surprises or difficult objects on its agenda that evening --
toughest was M78, which was very easy compared to M74 and M76, which I
had looked at a month ago. M42/43 showed a wealth of detail in the
binocular, and the winter Messier galactic clusters were all at least
granular and some -- like M41, M46, M48 and M44 -- well resolved. I
am pretty confident that the 10x50 will allow much easier detection of
all 109 Messier objects on my list, than did the 7x50 with which I made
my first Messier survey, nearly 20 years ago.

On the way out, I chased down some other members of the local club,
who had set up in a different part of the park. There was an interesting
array of equipment -- one person had a new 180 mm f/9 Astro-Physics
refractor, someone else had a Traveler, and there was an interesting hybrid,
a "Zeisstrophysics", comprising a 100 mm Zeiss lens with an Astro-Physics
tube and mount. There were a handful of fair-sized SCTs, up through a
Meade 12-inch LX200, and a modest array of Dobsons and smaller instruments.
We tried to split gamma-two Andromeda in the 12-inch Meade, but had no
luck -- seeing was too ratty. The AP 180 was giving wonderful views of
M42/43, with lots of color. I coffeed up for the drive home, chatted a
while, and left.

Well, I was going to tease you about the detailed identity of the
little wonder dwarf galaxy filter, but I am feeling generous and so
will forbear. It is not a high-tech multi-layer sculptured-bandpass
tribute to the vacuum-depositor's art at all. It is a Wratten 12, a
conventional broad-band photographer's filter of a kind available for
generations. This filter appears medium yellow in transmission,
because its spectral bandpass eliminates essentially all of the blue.
In fact, it is commonly called a "minus blue" filter. Dwarf galaxies
are made up almost entirely of old population II stars, and you know
what? They're red.

Clear sky...

--

Jay Reynolds Freeman -- fre...@netcom.com -- I speak only for myself.