Alan Whitman writes:
Saturday night, April 8-9, 2000, I finally got a Messier
Marathon score that I'm
happy with for latitude 49: 105 objects out of a possible 106 for this
latitude. Misses were M74 (invisible here by March 25th); M77 (invisible
here by March 30th); M79 (last seen April 2nd and invisible on April 8th as
it sets on a shallow arc 27 minutes before the end of twilight (AT); 45
minutes before AT M79's altitude was only 1.7 degrees and it had already
disappeared behind mountains); M30 (still invisible as it rises 56 minutes
after the beginning of morning twilight); and M33 (possibly still visible
with a light bucket and a more transparent sky).
Southern Interior British Columbia has not had any entirely clear night this
Messier Marathon season as there has not been a strong upper ridge at
anytime in the last two weeks -- we've usually just been playing the
northern edge of the clearer area. Any slight southward sag of the frontal
zone, or just a change in the wavelength of the leewaves behind the
mountains (which is what happened on the first four attempts, according to
the satellite photos) and we're dead. Saturday's situation was: a west -
east fairly clear slot extended north to south over only three degrees of
latitude, centred on the border (where my marathon site is). The forecast
charts were favourable. High cloud from a California low had crept
northwards across Washington State to Seattle's latitude, BUT the forecast
charts showed a flow which wouldn't allow it to spread further north and
SHOULD eventually push it back southwards slowly. The charts also showed a
very light flow over us which would mean no mountain wave clouds for a
change and steady seeing.
So Jim Failes and I went up Anarchist Mountain, east of the Okanagan Valley,
despite the streaky cirrus clouds and the denser cirrus visible on the north
horizon (the stationary frontal zone) and the much more worrisome south
horizon (the cirrus over central Washington). The 4.4-day-old crescent moon,
located only 6.5 degrees southwest of M1, was illuminating the cirrus.
After we found that M79 had already set behind the Washington Cascades
before we targeted it, 45 minutes before AT, Jim went searching for M110 as
missing on it would be disastrous. I spent a couple of minutes picking up
the southern open clusters M41, M50, M46, M47, and M93 in 7x50 binoculars
because I was worried about the dense cirrus in the southern sky. (M93 took
a couple of tries until it moved into a thinner spot.) With these secure I
went after M110 which was reasonably tough although the cirrus was thinner
in the M31 to M33 region than in most of the sky. Jim, having gotten M110
while I was getting the clusters noticed that M1 was in a break and wisely
nailed it. He suggested that I grab the opportunity, but I went from M110 to
While M33 had been visible in binoculars six days earlier, neither of us was
at all surprised that binoculars couldn't reveal M33 at its altitude of 4.2
degrees at the end of twilight, especially through thin moonlit cirrus. We
pinned our hopes on starhopping to NGC 604, the brightest HII region in M33.
Both of us searched unsuccessfully with our 8-inch Newtonians until M33 set
half an hour later. At some point I had taken a moment to pick up the
reflection nebula M78 when I noticed that Orion's Belt stars were in the
clear. I mentioned M78 to Jim, but M78 was still high and he wasn't willing
to concede defeat on M33 yet.... . Neither of us found NGC 604, but perhaps
a light bucket would have revealed it.
With four objects missed in the evening twilight, and with M30 known to be
invisible at this latitude in the dawn, we were still grimly determined to
crack 104. (Jim's personal best was 103, achieved in late March, 1998. Mine
was 102, achieved six days ago.) Since we didn't really expect to get
late-rising M55 (which isn't even considered a challenge down south in
Arizona), we could lose no others. Most objects in the western sky required
several attempts through the moonlit cirrus and time was flying. The orderly
observing schedule went by the wayside. At some point Jim realized that both
M78 and M41 were lost to him in dense cirrus. What a heartbraker, to miss on
M41 which is normally a naked-eye open cluster! About the same time I
realized that I didn't have the Pleiades checked off, a cluster normally
noted in twilight while lugging equipment from the car. Dense cirrus low in
the west made them invisible to the eye, but fortunately my 7x50s found
them. [If I had missed M45, nobody would be reading this report!!] With his
two tough losses Jim was now unable to improve on his previous best, so took
up lunar observing. I was close to giving up on the night myself as M1 was
completely invisible in the moon-illuminated cloud.
Freezing, I had stripped down to add more layers of clothing when Jim said
that a one-degree wide break was approaching M1. He monitored the area in my
scope until the break arrived and then starhopped to M1. He called me over
half-dressed and I only had to note the starhop from Zeta Tauri, swing the
scope away, aim it again at Zeta and starhop to the still visible moonwashed
nebula. Thanks to Jim for saving my marathon! M1 was recorded at 2359 PDT,
but I had only found 26 objects, far behind schedule.
About this time the cirrus was thinning in much of the sky and moonset was
approaching. Having finally completed the objects in the southwest, west,
and northwest through the clouds, I had to decide whether it was worth
continuing after Jim left for his warm bed. The stars of Corvus were now
brighter in the critical south, so I decided to make the southern globular
M68 the test object. Once I bagged it through the thinning cirrus, I decided
to stick it out. The Leo and Virgo galaxies fell very quickly, thanks to the
practise of my recent marathons. The contortions necessary to hunt the
galaxies in the Ursa Major and Canes Venatici group in the zenith were
unpleasant, but only M102 requires an actual starhop. The others are
distinctive enough that aiming at the right general area and sweeping will
turn them up. The 39 objects from Leo through Virgo took only two hours and
I was almost back on schedule. Most heartening was the clear view of M83 --
the Washington State cirrus had broken up into thin bands and was retreating
southwards as forecast, so there was hope for the globulars in southern
Sagittarius! Having earlier used my old-fashioned engraved setting circles
to find M76 in the murk, I now went back to the now clear northern sky and
starhopped to M76 due north, as the planetary is circumpolar here.
I finished the Ophiuchus and Scorpius globulars by 0300, and actually had
time to take advantage of the steady seeing and enjoy 116x views of M80 and
M62. My last good medium power view of southern M62 was during the 1998
marathon, which was also a night of steady seeing.
Morning twilight was to begin at 0422. My final rush through Aquarius and
southern Sagittarius began at 0410:
0411 M2 at an altitude of 8.0 degrees with setting circles. Easy.
0419 M54 at an altitude of 4.5 degrees by starhopping. Easy.
0422 M69 at an altitude of 4.8 degrees by setting circles. Easy.
0425 M70 at an altitude of 4.2 degrees by starhopping from M69. Not hard.
0429 M75 at an altitude of 6.0 degrees by setting circles. Easy.
0438 M73 at an altitude of 8.1 degrees using circles. Difficult, in cirrus.
0443 M72 at an altitude of 9.7 degrees by starhopping from M73. Very tough.
(I had failed on M72 right after M2 as it was still too low.)
0455 M55 at an altitude of 3.3 degrees (there were treetops in the 1.3
degree field), using setting circles. A slight glow was detectable at 50x by
moving the scope, but I might not have counted M55 just on this very
difficult view. But at 91x a dozen stars appeared at the limit of vision,
confirming this globular which I had not really expected to succeed with.
I starhopped to 100 objects and used old-fashioned engraved setting circles
for five objects in the rush at dawn. In response to the writer who
criticized my use of setting circles for the 1998 marathon, I would point
out that at his location six degrees of latitude south of me the dawn
objects rise much earlier, rise on much steeper paths, and twilight begins
much later than it does here at latitude 49: his advantages far outweigh
mine. An equatorial mount is designed to be used with setting circles; it
would be pointless to pay for the capability and not use it when it aids
observing. Finally, my modest 8-inch scope only has a 6x30 finder which is
not suitable for fast starhopping in the starpoor wastes of Aquarius and
eastern Sagittarius during twilight.