Alan Whitman's 2004 Messier Marathon
The local Penticton, British Columbia club had a Messier Marathon planned
for Saturday, but Friday's satellite images convinced me that I should take
advantage of Friday's crystalline skies instead -- Saturday looked poor (as
it turned out to be). I chose my marathon observing site four years ago
after driving hundreds of kilometres of Okanagan Valley back roads because
it has the best horizons that I can find: treeless fall-away horizons to
the south and west and a slight upslope to about 4 degrees altitude to the
east. (You can't drive the unplowed road to the peak of Mt. Kobau before
June.) My site is at 4000 feet on Anarchist Mountain (actually a plateau),
is less than a mile north of the 49th parallel (the US border), and is on a
gravel country road leading to a farming community, Sidley Mountain Road.
Fenced fields prevent you from setting up off the road, but traffic is
normally light, especially after about 9:30 PM. (More traffic on Friday
evening than on any other evening that I have been there, though -- not
surprisingly. Friendly folk -- many stop with their lights on and want to
chat, including someone just as I had started starhopping to M74 -- just
great for critical dark-adaption -- hope that he didn't mind me conversing
with my back turned to him and my hands over my eyes ! Most of them do
drive by very slowly so as not to raise dust, or perhaps to see whether you
are a weirdo-threat.)
I used the club's 8-inch f/6 Skywatcher Dob at 60x (an old Meade 20mm
Erfle), my 7x50 binoculars, and my unaided eyes -- whatever was fastest for
At the beginning there was a persistent 4-degree wide band of cloud in the
west. Fortunately it turned out to be just above M77 and M74, but it
complicated the starhop down to those two. Got M77 first, then a ghostly
but definite M74 (to my surprise), and all of the evening Messiers. Getting
all of the evening objects was a first for me, but this was nine days
earlier than I've ever done a Messier Marathon before and the transparency
was excellent. The zodiacal light was very bright. Seeing was good, based
on views of Jupiter around midnight.
Got the first straight 102 objects although I wasn't very efficient. This
was my first marathon in four years and there are MANY Messiers that I
haven't viewed since the last marathon. So I lingered for a minute or more
over many of them instead of moving on promptly as one should. On M83 I
raised the power to 93x and had by far my best 8-inch view of this galaxy:
I glimpsed not only the central bar, but also one of the two southern
spiral arms. (Seeing this detail with the 8-inch is probably a result of
knowing what to look for, having viewed M83 in Australia from whence all
three arms were visible with a 14.5-inch Dob.) Earlier I had lingered too
long over M101 at about 60 degrees altitude -- at 93x it showed a fairly
faint nucleus, two barely discernable spiral arms, and several knots.
All of these overlong looks added up to the loss of my normal 1 AM nap when
marathoning -- I had frittered away my extra time. I had little sleep the
previous night and haven't done an all-nighter in three years. But I
needn't have worried about keeping awake -- the temperature of -7 degrees
Celsius and a breeze kept me wide-awake. There is always a downslope
drainage wind at this site from the north-east and I have never had any
problem with eyepieces or finders dewing (frosting) up.
About 2AM persistent thick cloud appeared on the southern to SSE horizon,
solid to an altitude of about 4 degrees with some bands for a couple of
more degrees above that. This was worrying, because M69, M70, M54, and M75
don't get any higher than an altitude of 4 degrees at this latitude until
about 20 minutes after twilight begins.
I had to delay going after M19 and low M62 until a thin spot came along.
The 7x50s found M6 in a narrow clear band between the dense cloud on the
south horizon and the next cirrus streak above. But I had a heck of a time
with M7 which was buried behind the dense cloud. The 7x50s finally got the
bright cluster through a thin spot, but this repeated sweeping along the
horizon looking for a fortuitous hole was very time-consuming and it was
after the beginning of astronomical twilight (AT) before M7 finally peeked
M2 was the last object that I logged, seven minutes after AT when it had
risen 2 degrees above the lowest dip on my site's eastern horizon. (It
would have been 5.6 degrees above a flat horizon.)
Since M69, M70, and M54 were buried in cloud, and M75 was either buried or
perhaps in cirrus at best, my only remaining possible targets were M72 and
M73. (At this latitude, 10 minutes after AT M69 has risen to only 3.1
degrees compared to 19 degrees at AT in southern Arizona, the proper place
to do a Messier Marathon. M30 is not visible during marathon season from
this latitude and M55 doesn't become possible here until about April 8th.)
The hassle with M7 had made me several minutes late in starting the starhop
from Enif and Alpha Equulei down to M2 (visible in the finder) and so the
twilight was too advanced by the time that I starhopped to faint M72. I
"suspected" M72 but didn't count it. I also logged M73 as only "suspected"
because I only glimpsed two stars, not the expected Y-shape of four stars.
Thirty hours later I realized that since magnitude 3.8 Epsilon Aqr was
fading from naked-eye visibility at the start of the starhop, there was no
way that I should have expected to see the two fainter stars in M73 at
low-power in bright twilight. So I now believe that the pair of stars that
I glimpsed were indeed the two brightest stars in M73. That brings my score
up to 103, compared to my best score of 105 set April 8/9, 2000 (that year
moonlit Cirrus clouds cost me M33).
If it hadn't been for the cloud to the south obscuring the four Sagittarius
globulars, I MIGHT have managed a score of 106? That cloud finally moved on
about 30 minutes after AT and I went after M54 then, but the sky was far
too bright. While sweeping for the globular I repeatedly glimpsed a fuzzy
in the eyepiece, but it was very elongated rather than round -- perhaps a
cirrus patch faintly illuminated by the sun?
So I missed seven Messiers, four of them due to the thick cloud on the
southern horizon from 2AM until about 4:40 AM. I checked several hours of
satellite images after I returned home and was able to identify the thick
patch of cirrostratus from its motion -- it was located over the
southernmost fifth of Washington State ! The northern edge of that patch
was about 180 miles south of my observing site. As Guy Mackie, one of my
clubmates, commented, "That's marathoning."
Increasing cirrus streaks were showing up elsewhere in the sky by 5AM and
by the time that I got home at 7AM Saturday we had overcast cirrostratus.
If we get a chance on Monday or Tuesday I'm going to try again to improve
on my 2000 score of 105 -- I was very rusty Saturday morning after not
marathoning for four years. I'm convinced that 106 is possible from
latitude 49 degrees North on a cloudless night. But some March I'm going to
do it right from Arizona where only M74 and M30 would be at all challenging.
At 8 PM Monday evening the moon will be mag -7.5, at 4 degrees altitude,
and sets at 8:31 PM which is 30 minutes after AT ends. The moon is only 6.9
degrees below M74 and 17 degrees from M77. I don't know whether the moon
will kill any chance for M74 -- I have never tried observing a deep-sky
object only 7 degrees away from a 2.4-day-old moon. The main problem with
M74 is the bright zodiacal light and that unavoidable problem MAY be much
more of a problem than scattered light from a mag -7.5 lunar crescent IF
the transparency is superb on Monday evening as it should be since British
Columbia will be just behind a Pacific cold front. Has anyone succeeded
with M74 that close (7 degrees) to a 2.4-day-old moon?
Penticton, British Columbia