First Messier Marathon at the 36" telescope

We held the Fitz-Randolph Observatory's first "Messier Marathon" on the night of March 19-20, 2001. The Messier catalog of deep sky objects was compiled by the comet hunter Charles Messier in the 18th century as a kind of list of "annoying things in the sky that are not comets", and includes many of the brightest visible galaxies, star clusters and nebula. The first Messier Marathons ever were held in 1978-1979 after it was realized that almost all the objects on this list could be viewed on a single night for a one week period in March. Of the 110 objects on Messier's list, 109 of them are theoretically visible on a perfect night within a few days of March 15 at a latitude of 40 degrees north.

Knowing from past experience that there are two critical periods in the marathon, one at sunset to catch the objects setting just after the sun, and one before dawn to catch the objects rising just before the sun, we arrived at the observatory well before astronomical twilight. Also knowing that the sunset objects are very low in the sky and setting fast, we set up a small telescope and binoculars on the roof to insure that we had flexibility for observing in case the view in the 36" was blocked by the dome, buildings, or other obstructions. It was good that we did. The first few objects, the Andromeda galaxy and companions, logged in a little after 7 p.m., were visible only from the rooftop. One of these, M110, is one of the notoriously difficult objects to see in the twilight sky - we picked it up from the rooftop in a 4 inch telescope. It was in this period that we missed our only object, M74, a galaxy in Pisces, because the view of the 36" telescope to the north is obscured at the horizon by some naughty pine trees that have grown too tall right next to the dome.

After the initial rush period, we settled into an observing routine in which we viewed many objects from both the rooftop telescopes and the 36", even taking time to notice how great many of them looked. Many people came by during this period to help out and observe. Along the way there was some hilarity in getting to the eyepiece for objects in the northern sky, and some mis-typed coordinates that tested our observing honesty (we passed the test). By 11:20 we had completed the first 70 objects, including the galaxy cluster in Virgo ("heartbreak hill" for people doing this with small telescopes without setting circles.) At this part of the Marathon there is a natural break (if you are an experienced observer, or are doing the marathon with computer control, like we were) where you have to wait 2 hours for the next round of objects to rise. Wise people would probably go home at this point, but we went down to the Dunkin Donuts on route 1 for a caffeine and sugar pick-me-up.

Suitably recharged, we started up again at 1 a.m. Things went relatively smoothly then till dawn. There were a few more periods of waiting for objects to rise, most notably between about 3 and 4 a.m. We used this period to enter the coordinates for the last 15-20 objects into a control file to help with the pre-dawn rush. There were a few scary times when Norm punched the wrong button on the computer console and the whole system crashed, turning off all the motors and filling the dome with an ominous silence, but the system re-started without a problem. For the last 5 or so objects we had to use manual over-ride to force the telescope into very low altitude positions, less than 10 degrees above the horizon. For many of those we were viewing with just the top sliver of the mirror - the telescope was essentially pointing directly at the supporting wall of the dome. We logged our last object at 5:02 a.m.

The combination of everything - the power of the 36" to see very faint objects, the spectacularly beautiful night, the convenient rooftop, the warm room in the basement, the computer control of the telescope and dome, and the good company - made for the best possible conditions for having a Messier marathon. In the end we observed 108 of the possible 109 objects, no small feat. Next year Norm wants to have the computer do the whole thing by itself and have a "Messier marathon web cast" so the participants don't have to stay up all night in the cold.

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