After having my finder dew over at Montebello last night, I decided to better arm myself for Saturday's Messier marathon. I dropped by a Radio Shack in Palo Alto Saturday morning, and bought a few dollars of resistors, some wire, alligator clips, and a simple holder for eight AA batteries. Using some simple directions in an old Sky and Telescope article (see http://www.skypub.com/tips/tricks/dew.html), I rigged up a simple dew heator for the objective and eyepiece of my 7x35 finder. The two rings of resistors went together quickly with twisting and electrical tape. The final product is simple, light weight, and delivers 1.6 watts to the finder. Total cost was about $5.00.
The home-made dew heater worked great under truly battlefield conditions at Pacheco State Park Saturday night. I drove through two brief showers on my way to the Park, and thought the night might be a total washout. However, when I arrived around sundown, the sky was beginning to clear to the west. I quickly set up my Starmaster 7 inch Dob, clipped the finder's dew heater leads to the AA battery pack, and got out my Don Machholz Messier Marathon Observer's Guide. This is a very cheap and useful guide, with both large scale finder charts and telescope eyepiece fields for each object (stars down to mag 10), and a well worked out observing order. Rolling clouds reaked havoc with the Messier Marathon script, and added an element of challenge to finding many of the early objects. In addition, this was a truly wet observing night, with mist in the air at times, wet grass, and dew soaking everything. The heater-equiped finder stayed clear the whole observing session, however, and worked very well in combination with the charts in Don's book. The finder is a hacksawed half of a 7x35 pair of Tasco binoculars (the model that Jay Freeman recommends as second rate but good value in his beginner's FAQ). This provides a very convenient upright, straight-through view, reasonable magnfication, and a field of view of over 9 degrees (see November observing reports on Hacksaws, Telrads, and Dinder Scopes). Unlike my experience last Wednesday at Montebello, the simple, dew-free, magnifying finder made it simple to find everything I was looking for on Saturday night. The main telescope eyepiece for the night was a 24 to 8 mm Vixen zoom giving a magnfication of 40x to 120x in the Starmaster. This was also extremely convenient, since it was easy to zip back and forth between 1 degree eyepiece fields (good for locating objects), and a whole range of higher magnifications (good for picking best view of object).
Using this setup I found a total of 53 different Messier objects between about 7:20 and midnight, including M77, 74, 33, 31, 32, 110, 52, 103, 76, 34, 45, 79, 42, 43, 78, 1, 35, 37, 36, 38, 41, 93, 47, 46, 50, 48, 44, 67, 95, 96, 105, 65, 66, 81, 82, 97, 108, 109, 40, 106, 94, 63, 51, 101, 102, 60, 59, 58, 90, 89, 87, 99, 100. Along the way, there was plenty of time for several other nice views, including some of my favorite Non-Messier clusters: the Double Cluster, the Owl Cluster (457), the Dog Butt Cluster (Tau Canis Major), and two small clusters in Taurs near the top of Orions shield (NGC 1807 and 1817). NGC2477 in Puppis is a nice rich cluster I have mentioned before, easily as striking as many of the objects on the Messier list, and pretty but very low at Pacheco. I also picked up several other objects nearby the better known Messiers, including NGC 3384 by M105, NGC 3628 by M65 and M66, and NGC 3077 by M81. I particularly like the two small tight dimmer clusters near M35 and M38 (NGC 2158 and especially 1907). NGC 1931 was an unimpressive glow in Auriga, a clean-up object from the ongoing Hershel 400 list. I also looked up NGC 2818, an open cluster in Pyxis with a planetary nebula visible within it (2818A). This was much dimmer than the similar combination of cluster plus planetary in M46, but the 2818A planetary was large and plainly visible, and would probably make an interesting target for a larger scope.
The combination of the Marathon list and objects from other observing projects provided a great opportunity to compare and contrast different examples of clusters, galaxies, planetaries, and bright nebula. I was still happily chugging along on the Messier list when fog rolled in around midnight. I thought about waiting it out, but was starting to see signs of dew on the secondary of the Starmaster by midnight. Fixing that will have to be my next minor telescope project. (I have been considering a dew shield to block stray light anyway, and will see how that works before fooling around with trying to heat the secondary).
It was frustrating to see beautiful clear dark skies on the drive down from Pacheco at 1 am. Palo Alto was blanketed with low clouds. however, putting an end to any thoughts of continuing the second half of the Marathon with a dried out scope when I got back home. Half a Messier Marathon is still much better than I expected from the early weather reports, however. It was a fun night, and taught me several useful tricks for future swims, Marathons, and general stargazing sessions.