David,
Thanks very much for this. A great OR. I thoroughly enjoyed it.
Regards, Bob J.
--- David Kingsley <kingsley@pmgm2.stanford.edu> wrote:
> I was flying to New York last Saturday morning at 8 am, so headed to
> Coe last Friday night for a night of observing before the trip. The
>
> only time I had ever tried a Messier Marathon was the famous
> underwater star party at Pacheco back in 1999. I lasted longer than
> most that night, with help from a battery powered dew heater built
> quickly from Radio Shack parts before the soaking wet night of myth
> and legend (see "Swimming a Marathon,
> http://observers.org/reports/99.03.20.2.html). However, the fog
> rolled across Pacheco around midnight five years ago, and I ended the
>
> night with only 53 objects from the marathon.
>
> I have long since finished the Messier List. Although I check back
> on some favorite Messiers nearly every observing session, it has been
>
> years since I have looked at some of the objects. I decided that
> last weekend would be a good time to try another Marathon, break in
>
> a new scope, and welcome the spring observing season after a long wet
>
> winter.
>
> I brought both my 14.5 inch Starmaster and a one-month old 105 mm AP
> Traveler to Henry Coe on Friday night. I've had the Traveler out in
> the backyard a lot looking at doubles, the moon, and planets, and
> once to Fremont Peak, but on a night I mostly hunted objects with
> larger aperture. Last Friday was the first extended observing I have
> done with the scope on a whole range of objects from a dark sky
> location.
>
> The Traveler worked great as a Marathon scope. I have it mounted on
> an older Vixen Custom D alt-az mount with wooden legs that I bought
> used on Astromart. This mount makes it possible to just grab the
> scope and push it around without releasing any clutches, very much
> like starhopping with a Dob. Once near an object,the slow motion
> controls on the mount make it simple to keep the scope centered on an
>
> object, and to make very fine position adjustments with almost no
> vibration. The counterweight on the mount means that I don't have to
>
> change balance positions of the scope as I point to different regions
>
> of the sky, or as I switch between different kinds of eyepieces.
> Both the scope and mount are also light enough to pick up and easily
>
> move around an observing area. I took advantage of this several times
>
> in the parking lot at Hentry Coe on Friday night. First to see
> around the tree that blocked part of the southern sky. Then to
> position myself in just the right position to pick off Omega Centauri
>
> near the horizon. Then to observe in the lee of a large truck when
> the wind picked up around 2 am. And finally to get the best view of
> the last Messier objects just rising from the eastern horizon near
> morning. I used an Orion 6x30 erect image finder for star hop
> through the entire night, based on the observing order and finder
> charts in the Don Machholz Messier Marathon book.
>
> I expected I would miss M74 at dusk in the western sky, and did.
> This is one of the toughest setting objects for a spring marathon,
> and is located in the brightest portion of the sky from Henry Coe. I
>
> was more surprised at how hard both M110 and M33 turned out to be in
> the western sky after sunset. I was able to log both with averted
> vision through the Traveler after lots of looking with different
> eyepieces, but that's pretty sad for objects that are normally
> binocular eye candy when they are better placed in the sky. Once I
> was past the first half dozen or so objects, it was pretty easy to
> pick off everything else cruising through the much better placed
> winter and spring constellations. The pace picked up a bit again at
>
> the end of the list, but mostly because I was worried about getting
> everything packed up again, driving home, unloading the scopes,
> packing for my trip, and still having time to get to the San
> Francisco airport. I logged a total of 108 Messiers through the
> Traveler between 7:30 and 3:45 am, missing only M74 at sundown, and
> M30 at sunrise.
>
> My favorite views of the night were usually pairs or trios of objects
>
> all visible in the same field of view of the Traveler with a 9 mm
> Nagler eyepiece. That combination gives an exit pupil of 1.5 mm, a
> magnification of 66x and a field of view of about 1 and a quarter
> degrees, a great combination for a whole range of objects in the
> Marathon. One of the highlight "double features" of the night was
> broad sparkling M35 next to the unresolved puff of the much more
> distant open cluster NGC2158. Other nice multiple object views were
> the paired open clusters M38 and NGC1907 in Auriga; the view of M105
>
> in an arc of decreasing brightness with NGC3384 and NGC3389; the
> M65/M66/Ngc3628 triplet in Leo; the spectacular paired galaxies M81
> and M82 in Ursa major; and the classic triangle of galaxies
> M84/M86/NGC4388 in Virgo, with a fourth much smaller galaxy
> detectable in the middle (NGC4387).
>
> I also enjoyed two pairings of very different kinds of objects in the
>
> same field. The planetary nebula in M46 is a beautiful view against
> the backdrop of the rich open cluster. This pairing makes M46 of my
> favorite clusters on the list, and one I usually check in on several
> times a year during the winter. However, it has been a long time
> since I had looked at the Owl Nebula M97. It appeared as a large
> round puff with darker interior blotches last Friday. With the
> field of view of the Traveler, the large edge on galaxy M108 was
> visible as a mottled gash in the same eyepiece field. Although the
> dying star and island universe differ in physical diameter by nearly
>
> 50,000 times (couple of light years vs. 100,000 light years), their
> distance from earth also differs by a roughly similar factor (couple
> of thousand light years vs. 45 million light years). The enormously
> greater size of the island universe is balanced by its enormously
> greater distance, producing a "nebula" that has a similar apparent
> size to the Owl Nebula in our own Milky Way.
>
> I only used the 14.5 inch scope occasionally during the night. There
>
> was plenty of time to look at things whiles waiting for summer
> objects to rise, so I did a little bit of comparison viewing of M
> objects at different aperture, looked up the Arp peculiar galaxy pair
>
> NGC3395/3396 in Leo Minor, and chased down some of the supernova
> reported in 2004. (SN2004A was still visible in NGC6207, but I
> couldn't split SN2004ab from the bright core of NGC5054). Although I
>
> always like to have a large aperture scope with me if I am going to
> take the time to travel to a semi-dark site, on this particular
> night, I would have done better to only bring the Traveler. The
> extra time required to set up the large Dob meant that I had no time
> to wander around the parking lot when I first arrived after sunset.
> I would have enjoyed talking with the other observers already there,
> but ended up rushed to set up both scopes and get started with the
> Marathon as soon as skies got dark. Tearing down, transporting, and
>
> unpacking both scopes back at home also increased the number of
> things to be be done to catch my flight, and created an unwelcome
> rush at the end of the night.
>
> And for surveying eye candy objects like Messiers, the Traveler was
>
> plenty of aperture for quick, beautiful views. In fact, the bright
> objects seen through the Traveler were much more visually striking
> than the faint objects chased down with the larger aperture scope. I
>
> think most deep sky observers have a tendency to move up in aperture,
>
> but then to primarily use the increased aperture to hunt ever fainter
>
> objects.The net result is an expanded list of faint fuzzies that are
> within the range of the telescope, but lots of eyepiece time gets
> spent looking for objects on the edge of visibility, regardless of
> aperture. I have done much the same as I moved from a 7 inch to
> 14.5 inch Dob. (Hunting lots of extraglactic globular clusters in
> M31 is a good example of a project that requires aperture, patience,
>
> and a willingness to push the edges of what can be seen with any
> given scope). Howevever, an alternative use of aperture is to use
> the extra resolving power to see more detail in bright objects. I
> have found that the 14.5 inch scope has given me the best views I
> have ever had of many bright objects, including globular clusters,
> the planets, and the moon itself (see, for example, "High Moon"
> http://observers.org/reports/2003.09.13.3.htm). Last fall at LSA, I
> also started a project to observe all the objects in the Hubble Atlas
>
> of Galaxies with the 14.5 inch scope. That project is based largely
> on the brightest galaxies in the sky, but carefully examining those
> galaxies for morphology and structure, and comparing how much can be
>
> seen in the eyepiece compared to the beautiful photographic prints in
>
> the oversize Hubble atlas. That project has already convinced me that
>
> I should go back through all the Messier objects with the 14.5 scope
> as well, again focusing on detail and structure visible within the
> bright objects. To do that, however, I will pick times that are
> optimal for observing each object, and spend lots of time playing
> with magnifications, filters, and eyepieces as each object is as
> close as possible to the zenith.
>
>
> Some final conclusions after finally doing most of a Messier
> Marathon.
>
> 1) The Messier Marathon is obviously not the best way to actually
> observe the Messier objects. There is not enough time to study each
>
> one in detail, or to explore all the other interesting objects
> nearby. By design, many of the objects are just setting or just
> rising, and so are only detectable rather than beautiful. We all
> know that objects are best observed when they are high in the sky.
> But there is nothing like seeing some of the best objects in the
> heavens reduced to dim nothings to remind you to design your
> observing sessions around what is actually UP, not just above the
> horizon.
>
> 2) The Marathon has the huge compensating virtues of providing a
> one-night overview and summary of the sky. It is a great way to
> revisit favorites you have seen before, and to compare the sizes,
> shapes, brightness, concentration of lots of different galaxies,
> open clusters, nebula, and globulars in a single session.
> This overview aspect of the Marathon struck me again when I arrived
>
> in New York City last Saturday, and spent Sunday afternoon going
> through galleries of the American Museum of Natural History with my
> old college roommate. There were tons of exhibit rooms at the museum
>
> that were organized around geographical area of the world, or
> animals of a particular type. However, one of the most striking
> exhibits was the much newer Hall of Biodiversity. The highlight of
> this exhibit was a spectacular wall nearly completely covered with
> all kinds of animals from a whole range of different groups.
> Related animals were grouped in columns, allowing you to compare the
> diversity of form within mammals, or birds, or insects, or
> crustaceans, or molluscs, etc; as well as the differences and
> similarities between animals in different columns (see
> http://www.the-scientist.com/yr1998/august/aug_art/am_mus.jpg for
> some idea of the juxtaposition, though the wall itself is only
> visible in the background). Looking at everything together in one
> giant display was a very different experience than the more detailed
> look at more focused exhibits on individual groups. But studying
> everything together on that wall also gave a much better overview of
> the overall diversity of life on earth, and relationships between
> different groups.
>
> The Messier Marathon provides a similar Hall of Astrodiversity for
> astronomers. A great overview of both the major types of objects,
> and the tremendous diversity of objects within each class. And the
>
> whole night drives home again the large scale structure of our own
> galaxy.The early part of the Marathon is dominated by open clusters
> and emission nebula as we look outward into an arm of the MIlkyWay
> seen in the winter constellations. Then the galaxy rich regions of
> the sky emerge in the Spring constellations, as we look away from the
>
> dusty plane of our own galaxy. The night ends with an overwhelming
> number of clusters, nebula, and globular clusters as we stare towards
>
> the center of the Milky Way. The concentration of globular clusters
> on one side of the sky provided a key part of Shapley's original
> argument in 1918 that the sun and earth was located far from the
> center of the Milky Way. Going through the Messier Marathon forces
> you to think again about our position in the Galaxy, in the same way
>
> as the Hall of Biodiversity forces you to think again about our
> position and relationship to the long history of life on earth. I'm
>
> glad to have seen both overviews in a single weekend, despite the
> rush of both observing and travel.
>
> -David Kingsley
__________________________________
Do you Yahoo!?
Yahoo! Finance Tax Center - File online. File on time.
http://taxes.yahoo.com/filing.html
Received on Sun Mar 28 16:59:27 2004
