From: tflanders@my-deja.com (tflanders@my-deja.com)
Subject: Herschel 400 Retrospective (Long) 
Newsgroups: sci.astro.amateur
Date: 1999/07/15 

The project began in October 1997 when UPS delivered my 7-inch F/5.4
Starmaster Dob, and ended in the first hour of July 8, 1999, when I
observed the difficult globular cluster NGC 6426, the large bright
open cluster NGC 6664, and confirmed my sighting of the extremely
odd and obscure NGC 6540, which has been catalogued both as an open
and a globular cluster.

Before the Dob, I had owned three telescopes.  When I was a child,
my parents bought me a 4-inch GEM Newt from Edmund Scientific.  I
never managed to get much use from it, for a variety of reasons.
In the winter, we lived in an apartment in New York City, where I
was restricted to observing out of my window.  In the summer, we
lived in the country, but I usually went to bed before it was dark.
Above all, I lacked instruction and direction.  I was desperate to
look at the planets, but I didn't know how to find them in the sky.
And I certainly never figured out how to use the equatorial mount.
In retrospect, a few days of assistance from an experienced adult
would have made all the difference, but I was fiercely independent,
and not about to ask for help.  So that telescope was a false start.

Many years later, when I was taking a sabbatical from work, I spent a
winter by myself in the same country house that I had summered in as a
child, 20 miles from Albany, NY and 10 miles from Pittsfield, MA as
the crow flies.  Despite the proximity to those cities (metro areas
about 800,000 and 100,000 respectively) the skies are respectably
dark, with a zenith limiting magnitude around 6.0.  Having little
better to do, I decided to spend the long winter nights learning
the sky, with the aid of Peterson's Guide to the Stars and Planets
(1964 edition) and a pair of 7x35 binoculars.  I had two major
handicaps in this enterprise.  The 1964 edition of Peterson's
Guide has some good material in it, but it is not good for an
aspiring observer.  The photographic charts are hard to correlate
with the sky, and there is very little direction about what objects
to observe, how to find them, and what to expect when you see them.
Possibly even more important, I was stymied for want of the cheapest
and simplest piece of equipment imaginable -- a ten-cent sheet of
red cellophane.  Peterson's Guide did mention that it was advisable
to use a red flashlight, but I didn't grasp just how much difference
it could make, so I made do with a regular flashlight shone through
my fingers, or at oblique angles.  As I result, I spent the better
part of my time outdoors recovering my dark adaptation after
consulting my charts.  However, I had lots and lots of time to
waste, so I learned the winter constellations pretty well.  I also
learned how to locate M31 with naked eye or binoculars any time
I want.  And if seeing something 2,000,000 light-years away with your
naked eyes doesn't stir your blood, you will never be a deep-sky
observer.

After that my observing career became dormant for the better part of
two decades.  Not totally dormant, I guess, because I kept the basic
outlines of the winter constellations, and picked up some of the
summer ones as well.  And I vividly remember one November night lying
on my back in Lincoln, Mass waiting for Leonids, with my trusty old
7x35 binoculars and Peterson's Guide at my side.  Browsing over the
sky between Gemini and the rising Leo, I noticed a bright hazy patch
of sky, and said to myself "I bet that's SOMETHING."  Pulling out
my binoculars, I found that M44 is something indeed!  It remains
one of the most satisfying observing experiences of my life, because
it was totally unplanned and I did it all on my own.

Then, in the fall of 1996, I was trying to think of a birthday present
for my nephew.  Being a conscientious uncle -- and a little beyond a
beginning amateur astronomer myself, even if I didn't realize it --
I didn't just run out to the local department store, but spent some
time researching and thinking about the problem.  In the course of
my researches, I realized that my nephew was too young for a telescope.
And I also realized that the person who really needed a telescope was
not my nephew, but me.  Why had I been waiting so long?

Being a cautious and frugal type, I wasn't about to sink $1000 in
a piece of equipment that I might or might not use.  So I bought an
Orion 4.5-inch GEM-Newt on the advice of Fred at F.C. Meichsner Co.,
the telescope dealer in Boston.  To make a long story short, this
was an OK telescope, but I found its quirks and limitations quite
frustrating, and I soon wanted better.  By this time, it was totally
obvious to me that I was going to be serious about astronomy this
time around, and that if I spent real money, it wouldn't just be
going down the drain.  So I bought a telescope that was pricey, to
slake my equipment lust, and tiny, to fit in my city apartment.
The Televue Ranger fit the bill perfectly.

I am the kind of person who takes pleasure from checking things
off lists, so I decided that I needed a project to go together
with the Ranger.  The project that I chose was observing all of
the Messier objects, which took me a little over half a year.
I looked at plenty of other stuff along the way, such as the Moon,
all the major planets except for Mercury and Pluto, one minor planet
(Vesta), one comet (Hale-Bopp), various non-Messier DSO's, and a
few double stars, but all along the Messier objects were my mainstay.

Long before I had finished the Messier list with the Ranger, I knew
that I was going to want a much bigger telescope.  I was pretty much
limited to 8 inches by the need to store it in my third-story walkup
apartment and to haul it back and forth to my parents' country house.
I considered the C5+, the Intes 6-inch Mak-Cass, the C8, and various
Dobs.  Eventually, I settled on the Starmaster 7-inch F/5.6 Dob
(actually F/5.4 in my case) a decision I have never regretted.
Aside from the fact that it doesn't have motor drive, it is hard
to imagine a better all-round telescope.  Stupendous 2.5-degree
wide fields, excellent high-powered planetary performance, superb
mechanics, simple, rugged, compact, and cheap: $850 including
shipping, handling, Telrad, and a retrofit with a superb 2-inch
Crayford focuser.

Soon after I received the new telescope, I decided that I was
going to need a new observing program, and I wanted something
more ambitious than the Messier list.  I really wanted to do
a full-sky survey, but I didn't have the stomach to undertake
surveying the sky square degree by square degree, so I needed
some kind of list.  I soon decided that the Astronomy League's
list of William Herschel's 400 greatest hits was going to be the
core, but I also wanted to broaden it to make it more comprehensive.
I eventually settled on the union of the Herschel 400, (published
on the Web at http://www.astronomical.org/alnotes/alher.html),
the Messier list, and Alan Dyer's list of the 110 best non-Messier
NGC and IC objects, published in the RASC Observer's Handboook and
on the Web at http://www.seds.org/messier/xtra/similar/rasc-ngc.html.
There is heavy overlap among these lists; fourteen of the Messier
objects (the ones that William Herschel catalogued) are in the
Herschel 400, and all but 28 or 29 of the RASC 110 are in the
Herschel 400.  As I tally them, there are 528 objects in the
combined list.

There is considerable ambiguity about the total number of objects,
depending on how you count objects with multiple NGC numbers.  In
some cases, such as M76 or the Rosette Nebula, separate NGC numbers
were assigned to what are, without question, just parts of the
same object, with no independent existence of their own.  In
other cases, such as the Antennae Galaxies, NGCs 4038 and 4039,
there are two clearly distinct, interacting objects.  In yet
other cases, such as the galaxy NGC 4656/4657 or the open cluster
NGC 6882/6885, it is not altogether clear whether there are one
or two objects involved.  The most confusing case is the Veil
Nebula, which is all a single supernova remnant, but from the
observational point of view is two distinct, disjoint objects.
The western half is NGC 6960, while the eastern half has two
NGC numbers: 6992 and 6995.

The list has a reasonable claim to being the 500 or so most
observationally interesting NGC and IC objects visible from
mid-northern latitudes with a medium-sized amateur telescope.
It certainly contains almost all of the really heavy hitters,
although the choices tend to be a little arbitrary in the
bottom half of the list.  The most deserving NGC object that
I have yet seen that is not on the list is NGC 2359 in Canis
Major, also known as the Duck Nebula.  This is the remnant
of a Wolf-Rayet star, and it is big, bright, and interesting.
I have no idea why Alan Dyer skipped it.  Possibly because it
is a little far south to be seen well from Canada.  I would
also have included NGC 4874 and NGC 4889, the two brightest
members of the great Coma Galaxy Cluster.  They are hard to
see with a 7-inch telescope, but not as hard as some of the
galaxies that did make the list.  They are interesting because
they are so far away, and therefore extremely small; it is
unusual to have to use high power just to make a galaxy
appear non-stellar.  And also they are the most accessible
representatives of an important class of objects, the great,
super-rich galaxy clusters.

There may well be other deserving NGC and IC objects that
I missed; after all, I was not surveying the whole sky.
I made an effort to observe other DSO's (especially galaxies)
if they were in close proximity to ones on my list, but I
had no choice but to concentrate on the list itself.  I
found NGC 4874 and 4889 only because they were mentioned
in Burnham's, 3C 273 because it was mentioned in the RASC
handbook, and NGC 2359 because Steve Mock of the Amateur
Telescope Makers of Boston was observing it through his
25-inch Dob.  Where, of course, it showed vastly better
than in my puny 7-inch scope.

The most prominent DSO's not on the list are the classes of
objects that are not in the NGC and the IC lists: big loose
open clusters like the Hyades or Stock 2, and dark nebulae.
Also quasars, of which I have observed only 3C 273.  Unless
you have a spectroscope or the resolving power of the Hubble
telescope, it is completely indistinguishable from a star;
the fascination lies in knowing what it is, and knowing that
it is well over one billion light-years distant.

---------------------------------------------------------------

The central purpose of the observing project was to exercise
my new telescope, so I restricted it to observations made with
that telescope.  Many objects on the list are readily visible
through the Ranger, or even through my 10X50 binoculars, but
that's not the point; the idea was to see what they looked
like through the 7-inch Dob.  Likewise, sightings using other
people's telescopes (typically much bigger than my own) didn't
count, although they might be useful guides to what to look
for when I used my own scope on the same objects.

I also wanted to do full justice to each of the objects --
not just detect it and move on, but spend enough time to feel
that I had captured most, or at least much, of what could be
seen through my telescope.  That led to a dilemma.  If I was
to take the "full justice" criterion to its extreme, I would
have to do all of my observing in perfect conditions under
totally dark skies.  But of course conditions are never perfect,
and skies are never totally dark.  Both of these are ideals that
can be approached but never reached.  I had access to reasonably
dark skies at my parents' house, but I could only go there on
weekends, maybe plus Thursday nights or Sunday nights at a
stretch, and dark moonless nights don't always fall on weekends,
especially during El Nino events.  To utilize the available
opportunities more fully, I had to do some of my observing
within commuting distance of my home in Cambridge, MA, meaning
that the skies would not be anyway near fully dark.

After a few attempts at finding places that were closer, or
places that were a little farther but darker, I settled on the
observing field of the Amateur Telescope Makers of Boston (ATMOB)
as my local observing site.  It typically takes me 50 minutes to
drive there at the tail end of rush hour, and 40 minutes to
return when the roads are empty.  This is just close enough
not to be overwhelmingly arduous, although it is far enough
so that I am reluctant to make the trip unless I am sure that
conditions will be good.  The skies at the ATMOB field aren't
great, but they are good enough to see most of the Herschel 400.
The zenith limiting magnitude is about 5.5, but huge intersecting
light domes from several nearby cities make large parts of the
sky unusable.  Worst of all, the surrounding suburbs cast a
dim pall stretching up from the horizon in every direction
except west and north-west, which makes it impossible to get
a good view of objects far south of the Celestial Equator.
When they are due south, they are in the light pollution, and
by the time they have gotten to the good part of the sky in
the west, they are too low to view.

Fortunately, my parents' house has complementary virtues.  The
worst part of the sky is the north-west, in the light dome of
Albany -- although truth be told, the sky is still darker to
the north-west than it is at the ATMOB, where north-west is
the best direction.  And south is the best direction at my
parents' house, looking straight down the backbone of the
Taconic mountains over towns whose population is measured
in small thousands until you reach greater metropolitan New
York a good hundred miles away.

I ended up with a division of labor between the two observing
sites.  When I was at my parents' house, I would first observe
objects in the far southern part of the sky, and then work my
way progressively north and east.  I tried to view all the
objects that were especially dim, which I might not be able
to see at the ATMOB.  I also tried to view all the especially
bright and large objects, because I wanted to be sure that I
did them full justice by observing them under dark skies.

At the ATMOB, where west is the best direction, I would mop up
objects that I had missed at my parents' house, and when I had
done with them, I worked my way down from the North Celestial
Pole, viewing objects that were always high in the sky and well
away from the light domes.  I never really got the best possible
view of any object at the ATMOB, but I figured that the view was
good enough for the majority of objects -- objects that were
bright enough so that I had no trouble seeing them, yet small
and/or dim enough so that I had no hope of seeing much detail
even in darker skies.  Occasionally, I would stumble on an
object that proved unexpectedly difficult or unexpectedly
interesting, in which case I would mark it down for a second
look when I got to my parents' house.

Keeping track of 528 objects turned out to be an unexpectedly
large problem in data management.  I initially attempted to do
it with paper and pencil, but I soon got bogged down in the task
of recording which objects I had observed, which remained to be
observed, which needed to be re-observed, and planning each
observing session accordingly.  Worst of all, I made mistakes,
and each mistake meant either painful correction with white-out
or re-doing the list from scratch.  I soon decided that a
computer was the only sane way to deal with the job.  Since
I am a computer programmer by profession, I didn't obtain
any special software for the purpose, but just hacked together
a collection of Sed and Perl scripts.

My primary star chart was Uranometria, but I soon got sick of
lugging around the whole south volume just to cover a few hours
of RA, so I printed out a whole bunch of supplementary charts
with Sky Map Pro covering the sky from the Equator down to 35S,
and stapled them together into booklets covering three hours
of RA apiece.  These had several advantages over Uranometria
aside from portability.  First, I restricted the DSO's to
objects brighter than mag 12.5, so I wouldn't be distracted
by things that I had no hope of seeing through my telescope.
Second, I had no compunction about getting them wet from dew
or marking them any old way that I chose.  Third, I could
select particularly dense areas and supplement my usual charts
covering roughly 20 degrees of declination by 1 hour of RA
with charts showing as much detail as I needed.  On the down
side, the slightly smaller format as opposed to Uranometria's
9x12 pages and the vastly inferior cartography of a computer
as contrasted with a master draftsman means that the coverage
of a chart printed by Sky Map is much worse than Uranometria's
coverage at the same scale.

I considered extending my comprehensive coverage of the sky
with computer-printed charts of the northern hemisphere, but
decided it would be far too much work.  I did, however, print
detailed charts of the galaxy band reaching up from Virgo through
Ursa Major, where Uranometria doesn't provide as much scale and
as many faint stars as I would like, while simultaneously
cluttering what scale it does provide with thousands of galaxies
that I have no hope of observing in a 7-inch scope.  I also printed
out index charts covering about three hours by thirty degrees, so
that I could underline the objects that I needed to observe and
cross them out after observing them.  There is no substitute
for seeing this information in two dimensions!  If you run down
a list in RA order, you end up skipping all over the place in
Dec, and vice versa.  Seeing all the objects charted together
with the stars gives me a pretty good sense of the possible
star-hopping strategies to cover them all efficiently.

-------------------------------------------------------------

I experimented with a fair number of different eyepieces, but
towards the end, I settled on using only two -- the Rini 35 mm
widefield with a 68-degree apparent FOV, and the LV 8 - 24 mm
zoom.  I used the Rini for starhopping.  Its 2.5-degree real
field of view made it possible to hop anywhere in the sky in
a couple of minutes, and frequently faster.  Nine out of ten
of my target objects were clearly visible in the Rini when I
got to them, in radical contradistinction to the situation
with a finder scope.  With bright objects or isolated objects,
I could just use my Telrad to point to the right part of the
sky, and the target would be sitting in field when I put my
eye to the eyepiece.  This didn't work so well with faint
objects; locating a galaxy with averted vision in a 68-degree
apparent field is more trouble than star-hopping to it.  And
it didn't work so well in galaxy clusters, where I might have
no trouble seeing my target, but lots of trouble picking it
out from its neighbors.

Once I found my object, I switched to the LV zoom.  The fact
that I was using only two EPs saved huge amounts of time.
I kept the Rini in one pocket and the zoom (plus the 1.25-inch
adapter) in the other, so I always knew exactly where to reach,
and the eyepieces never even thought of fogging up.  The LV
zoom provides 40X at the lower magnification and 120X at the
top, and this pretty well brackets the useful range for most
deep-sky objects in my 7-inch scope.  Truth be told, 60X to
180X would have been even better.  It is very rare (although
not unheard of) for an object to show better at 40X than at
60X, while many objects seem to better at 120X than at 110X,
suggesting that even higher powers might be better still.

On some occasions, I would slip in my 2X Barlow to get a higher
power, especially with planetary nebulae and globular clusters.
But I tended to avoid this because it disrupted the smooth
flow of my work, and I am sure that I missed things because
of the 120X barrier.

I also used a Lumicon UHC filter routinely with planetary
nebulae and emission nebulae, even in cases where I had no
trouble seeing the object and was reasonably sure that the
filter wouldn't show any additional detail.  One of the
fascinating things about these objects is that each one
responds differently to a nebula filter; on some, the
filter helps not at all whereas on others, it makes a huge
difference.  This may depend on the ratio of reflected light
to emission lines in each nebula, or it may depend on total
brightness, contrast, or (most likely) all of the above.
In any case, it is a worthy thing to note in its own right.

Most of the time, I didn't bother to screw the filter into
the eyepiece; I just held it between the eyepiece and my eye.
Moving the filter in and out of the field to "blink" the
object is by far the best way to judge how the filter affects
it, and it is often the fastest way to locate and/or identify
a planetary nebula, avoiding a fair amount of detail work with
the star charts.

-------------------------------------------------------------

All of the Messier objects are readily visible through a 7-inch
telescope even in the so-so skies at the ATMOB, and most of
them are spectacular.  Some of the fainter galaxies, however,
remained faint even with 7 inches of aperture, making me feel
less bad that I had had so much trouble seeing them with the
Ranger.  M91 comes to mind in particular, although in some
sense this is not a "true" Messier object; its identification
as NGC 4548 is recent and not very certain.

Neither the RASC 110 nor the Herschel 400 is meant to be
especially challenging, although it is hard to resist the
suspicion that a few objects were slipped into each of those
lists specifically because they are hard to observe.  For
the most part, however, they are lists of the greatest objects
that Messier missed; therefore, the listed objects tend to
be relatively big, bright, and easy to find.  A substantial
fraction of the objects are readily visible through binoculars,
or even to the naked eye, the most obvious example being the
Double Cluster.

However, a fair number on both lists gave me trouble, especially
when I tried to observe them at the ATMOB.  Somewhat to my surprise,
the hardest of the RASC 110 were nearly as hard as the hardest of
the Herschel 400; anybody attempting the RASC 110 as an easy
follow-up to the Messiers is in for a shock!  Without a UHC filter,
the RASC 110 might be even harder than the Herschel 400, since it
tends to stress faint nebulae.

Problems observing objects fell into three general categories:

  1. I just plain couldn't see anything where the object was
     supposed to be.
  2. I thought I saw something, but wasn't completely confident
     that it was real rather than an illusion.
  3. I was sure I saw something, but wasn't sure that it was
     the object in question.

If I failed to see an object at the ATMOB, my first resort was
to try again at my parents' house, and as often as not, the
object simply fell into my lap.  If this failed, I would use
Sky Map Pro to print out charts more detailed than Uranometria,
so that I could pinpoint precisely where to start looking.
Some of these objects were visible only at 80X or higher, and
at that power, the average field contains two, one, or no
stars charted in Uranometria, making that atlas pretty much
useless for locating them.  This, by the way, is a place where
motor drive would have helped greatly.  I could first have
pinpointed the location using a low-powered EP and then pumped
up the magnification to my heart's content.  But with an undriven
Dob, the pinpoint accuracy is lost as you shift from one EP
to another.

When I thought I saw an object but was not completely sure, I
would make as many notes as possible about the object.  For
galaxies, I would attempt to record the size and PA, although
these were usually pretty vague for objects seen only at the
border of averted vision.  In all cases, I would try to note
or sketch the surrounding star fields.  Then I would compare
my notes against other people's notes, against the most detailed
displays of Sky Map Pro or Guide or if those failed, against
the Digitalized Sky Survey (DSS).  In almost all cases, this
confirmed my observation.  As the confirmation percentage
rose, I began to have greater confidence in my abilities, and
I started to record as certain observations that I would once
have considered questionable.

In the case of the infamous Blinking Galaxy, NGC 6118, this
method almost failed me.  I made three unsuccessful attempts
to observe this galaxy, with a year between the first and
second, before it finally yielded on the fourth attempt.
Each time, I had to prepare more detailed charts to pinpoint
the location better, but the more I pinpointed the location,
the fewer unknowns I left open to confirm my observation.
If you start out by knowing *exactly* where something is
with respect to the surrounding stars, then recording the
surrounding stars loses all value as a confirmation!  I
knew that my fourth try was going to be my last chance.
I knew where to start looking within 4 or 5 arcminutes by
orienting myself with respect to a quadrilateral of 12th
magnitude stars, and if I knew any more than that, I would
never have confidence that my observation was more than an
artifact of my imagination.  At that point, my only recourses
would have been to seek out genuinely dark skies, or to use
a bigger telescope.

To make matters worse, NGC 6118 is located off a mag 6 star
close to a pair of mag 3 stars (one of my favorite naked-eye
star pairs, Yeds Prior and Posterior).  Any time I got lost,
I would have to re-find the location using these stars.  But
when you are looking for something this faint, a mag 3 star
is bright enough to ruin your dark adaptation for quite a
while, and even a mag 6 star is a major nuisance.  Again,
motor drive would have come very much in handy, to keep me
in the right location while I strained and struggled.

Fortunately, I found NGC 6118 on the fourth and last try.
It was one of the most unsatisfying observations of my life,
because I could not make it appear at will.  It would flick
into existence with my eyes in a certain orientation, and
then disappear again, and I could not formulate any sequence
of actions that would guarantee its existence.  Blinking
Galaxy indeed!  But it kept springing to life at exactly
the same spot, and I could even get a pretty good idea of
its PA.  On comparing my notes against the DSS, I found that
the PA was correct within twenty degrees or so, and the
position was correct within an arcminute or two -- less
than the size of the galaxy itself.  So there can't be a
whole lot of doubt that I found it.  But I won't regret a
thing if I never have to make such an observation again.

Even in cases where I was sure of my sightings, I would
compare my observations against other people's observing
notes, to see if I had missed anything.  If I had, I
would sometimes mark the object to be re-observed later.
My primary resources were:

  * Burnham, "Celestial Handbook"
  * Kepple and Sanner, "The Night Sky Observer's Guide"
  * Steve Coe's observing notes on the Saguaro Observing Club
    web site at http://www.saguaroastro.org/archive/obsnotes.htm.
  * Steve Gottlieb's notes on all NGC objects observable from
    California at http://www.ngcic.org/gottlieb/default.htm.
  * The Digitized Sky Survey, at
    http://stdatu.stsci.edu/dss/dss_form.html.

Burnham's is always fun to read, but it was of limited value
to me, because Burnham simply doesn't cover enough objects.
The chances were very small that Burnham would have a detailed
description of any given object on my list, especially the
faint and obscure objects that gave me the most trouble.

Kepple and Sanner only became available a couple of months
ago, at the very end of my project.  I wish I had had it sooner.
The observing notes are quite useful, but what is really
amazing about this work is the vast number of sketches and
photographs.  Kepple and Sanner cover all, or almost all,
of the objects on my list, sometimes at considerable length.

Steve Coe's notes cover all of the major objects in the sky
as visible from Arizona, gathered mostly with a 13" Dob, but
also with 8" and 17.5" scopes.  They were my primary resource
before I found Steve Gottlieb's notes, and even after, they
continued to provide a wealth of information.  But while Steve
Coe's notes are superb, Steve Gottlieb's are in another class
entirely.  His project is utterly audacious -- to make definitive
visual observations of the entire NGC, insofar as it is
visible from his latitude, cross-checking them against the
original NGC and all available scholarly sources.  I am not
enough of an expert to say how well he has succeeded, but
I found his observations to be consistent, reliable, detailed,
and clear in a way that was not true of any other source.

The Digitized Sky Survey is the resource of last resort.
Its downside is that the photographic images frequently don't
look like the sky as seen by the human eye.  Its virtues are
that it is comprehensive, and it doesn't lie.  The deep-sky
objects in Uranometria come from the Revised New General
Catalog of Sulentic and Tifft, and the deep-sky objects
in Sky Map Pro and Guide come from the Saguaro Astronomy
Club (SAC) database.  Both of these databases are quite
unreliable as far as positions, sizes, and magnitudes are
concerned.  It is common for objects to be mis-charted by
5 arc-minutes or so with respect to the surrounding star
fields, which looms very large indeed when you are trying
to locate a faint object at 100X.  The DSS isn't much help
as far as magnitudes are concerned, but it shows the
relationship between objects and the surrounding stars
objectively and precisely.  The DSS is also interesting to
consult in the case of strange galaxies, because photographs
show clearly features that the eye can only guess at.

Aside from NGC 6118, none of the galaxies gave me much
trouble.  Some of them could be seen only with averted
vision at relatively high power, but once found, they
were generally unmistakable.  All galaxies (well, 99%
anyway) have a strong family resemblance; they are more
or less elliptical blobs concentrated towards the center
in varying degrees.  If you can see them at all, you
immediately know that they are galaxies.

Open clusters are just the opposite.  They are frequently
easy to see, but hard to distinguish.  This is particularly
true of sparse open clusters on rich star backgrounds --
and of course, most open clusters are in the Milky Way, so
they do have rich backgrounds.  My notes are filled with
comments to the effect "I know this is a cluster, but I
can't say why."  Judging by the literature, professionals
often have the same problem -- one often runs across the
phrase "suspected member."  In some cases, clusters that were
hard to discern at my normal observing powers of 60X or higher
became unmistakeable at low power, when more of the background
stars came into the field.  Conversely, some of the fainter open
clusters were completely invisible at low power, but turned into
lovely clouds of faint stars at higher power.  Probably the
hardest were the ones that were sparse, on rich backgrounds,
and also so faint that I could not resolve them at all, or
maybe resolve a few stars at best.  These appeared as faint
patches of light, like galaxies or globulars, but less regular.
NGC 136 in Cassiopeia and NGC 6583 in Sagittarius come to mind.

Many people complain that there are too many open clusters
in the Herschel 400; it seems that galaxies are more fashionable
than open clusters these days.  But I like open clusters --
a hangover, perhaps, from observing with the Ranger, for which
open clusters are clearly the best target.  Open clusters
keep you on your toes; no two are like each other.  My
biggest frustration was with things that looked to me like
single clusters but were catalogued as multiple entries,
notable NGC 1746 with its sub-clusters 1750 and 1758, and
NGC 6885 with its sub-cluster 6882.  It doesn't help that
the sizes and positions for these sub-clusters in the
"official" sources like the RNGC are clearly erroneous,
or that they are charted differently in different atlases.
I read all the sources I could find, and ultimately decided
that I didn't care.  They look like single clusters to me,
and that's good enough for me.

Globular clusters were an eye-opener.  I though I knew all
about globular clusters from the Messier list, which is
pretty heavy on these objects.  I realized how wrong I was
when I tried to find NGC 5053, charted right next to M53 in
Coma Berenices.  It isn't in any of my lists, but how could I
resist, with it sitting so near such a prominent object.
Mag 9.8 -- piece of cake, right?  After all, I knew from
the Messier list that all globular clusters have high
surface brightness, right?  Wrong!  There's plenty of
low surface-brightness globulars; its just that Messier
couldn't see any of them.  I never did find NGC 5053,
described in the literature as one of the poorest globular
clusters known, with only a few thousand stars.  I'll
have to go back and try again next spring.  NGC 6426 in
Oph, the third-from-last object that I found, was another
such.  It wasn't a major challenge, but it did require
averted vision even at high power.

Last but not least, nebulae, of the planetary, emission,
and reflective persuasions.  Some of them gave me lots of
grief.  The hardest of the planetaries was IC 289, from
the RASC 110.  Small, faint, and low surface brightness.
I finally found it at 32X with a UHC filter, but only after
I had pinpointed its location within a few minutes.  Having
found it, I could still see it at 105X without the filter --
just barely.

As for diffuse nebulae, I agonized for a long, long time over
NGC 1980, the nebula surrounding Iota Orionis, at the outer edge
of M42.  First I thought I saw it, then I decided it was an
illusion.  The problem is that this faint nebula surrounds an
overwhelmingly brilliant star, and it is extremely hard to
distinguish the nebula from the glow or haze that exists around
any bright star no matter how clean one's optics may be.  To
make matters worse, there is no clear gap between NGC 1980 and
M42, and the outer loop of M42 is a pretty tricky and irregular
object in its own right.  I finally concluded after careful
study that what I saw had a separate focus from M42, and that
it was brighter than the halos around comparable stars, and
asymmetric in a way that was not characteristic of those halos.
So I compromised, and concluded that what I saw was definitely
partly real and partly illusion.

The Bubble Nebula (NGC 7635) another contribution from the
RASC 110, proved almost as frustrating as NGC 1980.  Again, it
is very faint and surrounds a pretty bright star.  In this
case, however, there is another even brighter star in the
same field which does not have a comparable haze, so it
is immediately obvious that NGC 7635 is real.  Also, it
is not at all symmetric around its star, but stretches out
almost entirely to the NNW -- at least, that is the visual
impression.  Star charts and photographs tell a rather
different story.

The nebula around NGC 2264, the Christmas Tree cluster in
Monoceros, turned out to be difficult because of its vast
size.  The famous S end, containing the dark Cone Nebula,
is quite obvious, although I could not see the Cone itself.
But on the N end, the nebula seems to stretch on and on
forever, across many telescope fields.  Much like NGC
7000, the North American Nebula, but more so.  I never
did find anywhere on the N where I could definitely
say that the NGC 2264 nebula ends.  It would all be quite
easy, no doubt, if these nebulae were on dark backgrounds,
but the Milky Way background is extremely bright both
for the Christmas Tree and for the North American Nebula.

My ultimate nemesis, though, was NGC 6540, which has been
variously classified as an open cluster and a globular.
This has it all -- small, faint, irregular, bright background,
and terrible location for those of us in the northern part
of the United States.  At latitude 42N, this object barely
clears 20 degrees off the horizon, and it doesn't stay
there for very long.  And it culminates at the time of year
when the transparency tends to be worst.  I was very glad
when I got a chance to nail it last weekend -- if I had
missed that chance, I might have had to wait another year.

Did I see it?  Well, I definitely saw something, and it was
very near, although not exactly at the charted location.
I make it out as 18:06.15, -27:46, as contrasted with
the 18:06.2, -27:49 listed in Steve Gottlieb's notes.
A faint circular patch, slightly concave to the S, about
one arcminute across, visible with averted vision at all
powers from 40X to 120X.  Was it really NGC 6540?  I don't
know.  Its position and shape happen to match perfectly
an arc of five or six stars shown on the DSS, and if NGC
6540 is a faint globular, then these stars are far too
bright to be part of it.  The DSS image shows strong hints
of weirdness in the immediate vicinity, which might be
a very faint globular cluster.  But there's weird stuff
all over this part of the sky; it is spang in the middle
of the Sagittarius Milky Way.  Looking at a one-degree
field centered on what I take to be NGC 6540, I see all
manner of suspicious star formations and patches of light;
I would never in a million years pick out NGC 6540 as the
one object that is real rather than illusory.  And if
the arc of stars in the DSS image happens to overlay
a globular cluster, I probably saw the arc of stars and
not the cluster.

Well, there it lies; I have done all I can by NGC 6540.
I am sure that I saw something, and comparing notes, I am
sure that it is the same thing that some other people have
seen.  I am also sure that it is not the same thing that
everybody has seen; everybody seems to have a different
idea of what NGC 6540 looks like.  As to who, if anyone,
is right, I certainly can't say.  The only thing that will
really satisfy me is to view it with a genuinely big
telescope under truly dark skies, preferably at a lower
latitude.  Or better, perhaps, to look at a CCD image that
is significant deeper and better resolved than the DSS.

-------------------------------------------------------

Was it all worth it?  What did it all mean?  Maybe it is
a little early for me to tell.  I am still basking in the
satisfaction of having completed this monumental task,
but this glow will surely fade soon.

It was certainly a monumental task.  It required about 70
observing sessions over a period of 21 months, which was
perhaps half of all the available clear, transparent,
moonless nights.  The sessions varied in length between
a few minutes, when the clouds parted and then closed in
again immediately, and six hours or so.  I also spent
at least as much time at desk work as I did under the
stars, pre-planning my observing sessions, transcribing
my notes, comparing my observations with other people's.
The desk work didn't seem so onerous because it was not
constrained by season, time, and weather.

Under the stars, I consistently averaged about four objects
an hour, which seems awfully slow.  Partly, I think, this
is because I consciously slowed myself down, forcing myself
to spend enough time on each object to be sure I had done it
justice.  Partly it is because some of the objects took lots
of time to find.  Most of them popped out pretty quickly
once I had pinpointed their locations, but the toughest
probably took several hours of staring, typically spread
over several sessions.

I spent lots of time star-hopping, about which I have mixed
feelings.  The best part of the star-hopping was the time
that I spent finding the best star to hop off, orienting
myself to unfamiliar parts of the sky and making out obscure
corners of familiar constellations.  The worst part was the
time that I spent getting lost in my charts, trying to figure
out which direction was up and down, which left and right.
This was always easiest relatively low in the sky and on the
meridian, where the chart was a simple 180-degree flip of the
eyepiece view, and hardest for objects near the zenith, where
I have no intuitive sense of direction.  This led to a paradox.
Objects in the far southern part of the sky were difficult
because they were well placed for only a few hours at very
specific times of year, but when they were well placed, they
were easy to navigate to and around.  Objects in the far north,
by contrast, rode high in the sky for long stretches of time,
but it was always hard to get them in the telescope's view.

The speed of star-hopping seemed to be at least proportional
to the area covered by my eyepiece, so that my Rini with its
2.5-degree field was at least six times faster than my LV
zoom at its widest setting, with its 1-degree field.  This
was a lesson that took a lot of time to learn.  When hopping
between closely-spaced objects, I would save time by leaving
the LV zoom in place, but as soon as I got lost, it was
always best to switch to the Rini immediately.  Likewise,
any time spent trying to re-find my location once lost
was almost always wasted; it is far easier to start again
with a known star or DSO.  Especially since once I had
done a particular hop, all the steps remained in short-term
memory for a while (even a night or two sometimes).  So after
I have spent minutes working out some particularly arduous
hop, I can repeat it in seconds.

The single accessory that would have saved me most time is
a finderscope, which would have given me a field even wider
than the Rini (although maybe not much!) and saved the time
of switching eyepieces.  But I find straight-through finders
uncomfortable at best, and especially so on a telescope with
a very low stance like my Dob.  And right-angle finders are
expensive, and it is hard to find any good place to stick
one after leaving space for the eyepiece and the Telrad.

A lot of the time was wasted in sheer inefficiency.  The
routine of finding an object, zooming in, and taking notes
required a lot of juggling eyepieces, red flashlight, charts,
notebooks, and eyeglasses in the dark, trying to protect
everything from dew, and not to lose anything.  My worst
mishap was putting my glasses down on the ground and then
stepping on them.  I managed to drive home with the one-
armed glasses balanced precariously on my nose and the
lenses rattling in the frame, but it was a costly mistake.

I also spent lots of time staring at the night sky and
spacing out, especially after my brain had been fried by
sleep deprivation.  But I never grudged that time; I love
to stare at the night sky and space out.  And listen to
the night sounds.  Last weekend, I almost jumped out of
my skin when a barred owl suddenly let loose from the tree
right over my head.  It gave me a new insight into the
evolutionary significance of that call.  There I was, one
hundred times the owl's size, and reduced to quaking jelly.
If I were a mouse, I would probably fall dead on the spot
from heart failure, saving the owl the trouble of hunting
me down.

And I do wish that I knew what that animal is that keeps
screaming at me from the edge of the field.  I suspect a
raccoon, but I have never seen one make such a sound.  And
surely that is a deer that keeps huffing and woofing
and thrashing in the underbrush.  And what about those
blood-curdling screams that I hear in the far distance?
Are they the death cries of prey or the victory calls of
the predator or animals of the same species trying to
duke it out?  And was that really a coyote that I heard
the other night?  Sure sounded like one, but it is the
first time I have heard that plaintive yap East of the
Mississippi.  Although I have seen two during the day,
so I know they are around.

Winter has its own joys and woes.  First and foremost joy
is that glorious sky.  I learned the winter sky first, and
it will always remain dearest to my heart.  The winter
Milky Way cannot rival the majesty of the summer Milky
Way, stretching from Cassiopeia through Cygnus, splitting
in half at the great rift, and stretching down to the
overwhelming brightness of Sagittarius.  But the gentle,
subtle winter Milky Way has a beauty of its own -- when
you can see it!  It is, alas, all but lost even at the
ex-urban ATMOB site, but it is lovely at my parents' house.

And what a great collection of constellations the winter
has!  None of those vague shapeless wonders that infest
the sky at other seasons.  Cassiopeia, Perseus, Auriga,
Gemini, each one brighter and more shapely than the next.
The Pleiades and Hyades, best of all the naked-eye clusters,
so conveniently placed right next to each other.  And of
course, everybody knows which is the greatest of the
constellations, because it exceeds all others by so
far, and in so many ways.  Orion, of course.  You might
argue about which constellation comes second, but Orion's
Big Dog is surely a contender.

And then there is the peace of the sound-muffling snow,
and the unearthly beauty when it is lit up by starlight.
There is lots of snow in my life.  At my parents' house,
it is reasonable to expect snow on the ground any time
from early November to mid March, and if you think
about it, those months probably contain 75% of all the
dark hours in the year.  One thing there is no shortage
of in the winter is time!  None of this staying up late
just to begin a session, or packing in early because the
sun is rising too soon.

On the other hand, there are my feet and my hands getting
ever more painfully cold, and my brain slowing to a dead
crawl, like a car engine that refuses to turn over on a
cold morning.  And after a fresh snow, worrying about
snow blowing onto my mirror.  Well, if it's not one thing,
its another; I'll take cold over mosquitos any day or night.

What have I gained from it all?  A lot.  When I started,
I was just a dabbler; now, I feel as though I have most of
the fundamentals under my belt.  I am ready to call myself
a true beginner -- first rank, as the Japaneese would say.
In the game of Go, there is a saying that it takes a thousand
games before you can call yourself a beginner.  In amateur
astronomy, it takes five hundred objects, more or less.

The Messier objects are concentrated in a dozen constellations,
but the Herschel 400 are spread over the better part of the
sky.  I now have at least a passing knowledge of the entire
naked-eye sky as it can be seen from my latitude.  I have
seen hundreds of galaxies of all sizes, shapes, and types,
elliptical, spiral, barred, and irregular, typical and
atypical, isolated and interacting.  When I see a new galaxy
now, I have a context in which to place it.  Likewise with
open and globular clusters and, to a lesser extent, with
nebulae.

What next?  I don't know.  In the background, I can always
hear the siren call of my next telescope.  I can always
look through big telescopes at the ATMOB, but they are
crippled there by light pollution.  Wouldn't it be great
to have 16 or 18 inches at my beck and call under the dark
skies at my parents' house?  Hmm, I'll think about it.
I'm not really sure that it is practical, nor am I sure
that I want to give myself such an enormous treat so early
on.  Unless I settle for a reasonable compromise like 12
inches, my next step up will probably be my last; I can't
really see going into the 20-inch arena as long as I have
a family to feed and care for.

Right at the moment, my biggest pull is in the opposite
direction -- to binoculars.  The night after I finished
the Herschel 400 was clear again, so I pulled out my 10x50
Ultimas and chased down the next 25 Messiers on my binocular
list.  Twenty-five objects plus the North American nebula
in a few hours -- not a bad haul after all that slow
patient work on the Herschel 400.  Plus Uranus seen through
the binoculars and naked eye and through my telescope.  And
that doesn't even count the time that I spent trying and
failing to see comet 10P Tempel 2.  Wish I had known at the
time that it was mag 12 and not mag 10!

As I said, the two major classes of objects not on the
combined Messier/RASC 110/Herschel 400 list are big loose
open clusters and dark nebulae.  And what better tool than
binoculars to see these?  And what better time of year
than the summer?  What a joy to lie on my back in a chaise
longue scanning over the sky at will instead of hunching
over an eyepiece hopping from one mag 9 star to the next
until I find some nearly invisible galaxy!

Yes, there were plenty of times when my 528-object project
seemed foolish or onerous or both.  Nights when I dragged
myself out reluctantly, knowing that I could not afford to
miss an opportunity, otherwise I might take a whole extra year
to complete the project.  Nights when everything went wrong.
But no matter how reluctant I was to go out, no matter how
much I struggled, there was always that moment of magical
transformation when I put my eye to the eyepiece and found
my first object, and felt my soul flowing out into the
universe through the telescope.  Ultimately, that is what
kept me going -- not the list itself, but the fact that
I really love looking through a telescope, that the
enchantment is renewed every time I do it.

The time I felt most foolish was the night last spring
when I finally crossed off the two-hundredth of the faint
galaxies between RA 9 and RA 14 that create a logistical
nightmare for anyone trying to complete the entire list.
Then I turned around, and at there at my back was the
summer Milky Way riding high in the sky, my first view
of it in over half a year.  I had ignored it completely
in favor of silly little mag 11 galaxies that I needed
for my list, and by then, I was too tired to look at it.

It had its frustrations, all right.  And I must admit that
this whole project-completion compulsion seemed and still
seems pretty childish to me as often as not.  But so what?
If I am childish, I might as well make the best of it.


--
    - Tony Flanders
      Cambridge, MA