Log, Dec 7, 2001
46 People. A pleasant, though brief, break in the cloudy weather allowed us a very decent evening at FDO. Pesky clouds hampered our view toward the southern horizon, but the rest of the sky remained mostly clear through the early evening. As predicted by the FDO Clear Sky Clock, a period of reduced transparency did plague the viewing of faint objects from about 9 PM onward. This was accompanied by some truly howling wind gusts that had everyone scurrying for the shelter of the dome. It certainly was a good thing that only a few small telescopes were set up in the yard - anything large would have been toppled or rattled to pieces!We were visited by many young folks and they were treated to their first views through a large telescope. Among them were the Cub Scouts of Troop 29 in Narragansett. And all were very impressed - if mostly a bit underdressed for the weather! We encourage all visitors to dress warmly, since there are few colder experiences than standing about in winter temps. waiting for a view through a scope. Some of the scouts were in shirtsleeves - they'll dress differently, for sure, on their next visit!First on the scene were Doug, Joe and Les, (Steve, Art and Dave also arrived a bit later) and they caught a nice look at the combined (and very bright) Space Shuttle Endeavor and ISS as it passed to the northwest, then faded into the Earth's shadow. A persistent drip, drip drip from the dome shutter (it had rained earlier in the day) kept the 16" scope covered for a bit longer than usual, but once up and running we enjoyed a fine view of Comet Linear WM1 - approx. mag. 5.6 in western Cetus. Had it not been for some thin cloudiness the comet would have been detectable with the naked eye. As it was, it showed a fine lengthening tail in both binoculars and the big scope. You will have to look soon to see this comet in your yard, as it will disappear into southern hemisphere skies in about 10 days.Using binoculars to view the comet Doug also noted how easy it was to spot the nearby bright galaxy NGC253, just over the border into Sculptor. Shining at magnitude 7.2 it is the fourth brightest galaxy in the heavens, after M31, M33 and M81. In the 16" this fine highly inclined spiral reveals a wealth of structure, and is a wonderful sight. Look for it with any kind of optical aid at all, especially when it's near the meridian.Just to NGC253's southeast lies the remarkable globular cluster NGC288 - large, but not especially bright, it is a challenging target in small apertures, partly because of its southerly position. In the 16" it is well resolved into a large sprinkling of faint stars. Moving northward, Joe and Doug also observed the bright elliptical galaxy NGC720 and the inclined and somewhat irregular spiral NGC908 - both in Cetus, and both about 10th magnitude.As the public began to arrive a clamor arose to view Saturn which was shining brightly in the east, just 4 days past opposition. It was a grand sight this evening, revealing fine shaded detail on the surface of the planet and several divisions in the rings. The Encke minima was observed, although not the Encke division itself. The globe of the planet was easily seen both through the transparent crepe ring, and through the open width of the Cassini division. We easily observed 6 moons, and this was one of the best views of Saturn we've ever enjoyed!Jupiter was next up, and although there were no moon transits or shadows to watch, the Great Red Spot was easily seen, having just passed Jupiter's central meridian. Each of the bright moons revealed themselves as crisp little globes, especially when we increased the magnification to 336X. Nearby we also enjoyed a fine look at the ever-popular Eskimo Nebula (NGC2392) and took a look at the lovely white double star Castor (Alpha Gem).Another all time favorite is the Great Orion Nebula, M42, and once again it didn't fail to amaze and enthrall our visitors! No one ever tires of looking at this magnificent object - with or without filters it is one of the great showpieces in the sky. Several visitors next asked to see a galaxy or two, so we turned the big scope up to look at the fine pair M81 and M82 in Ursa Major. Despite the light skyglow in the NE, these two galaxies are impressive in the 16" - especially the contrasty M82, with it's irregular internal structure. Also in Ursa Major we took a look at M97, the Owl Nebula, but it was only about 15 degrees above the horizon and difficult to see clearly. It earned "smudge of the week" honors for this night.As the air became quite hazy for a spell we took a look at a few multiple stars of note - the impressive Rigel (Beta Orionis) and the quadruple system Sigma Orionis. Sirius dazzled at 336X, but we saw no trace of its faint dwarf companion. As the skies cleared again we enjoyed a look at the peculiar NGC2261 - Hubble's Variable Nebula. Small and fan shaped, resembling a comet, this odd nebula has undergone frequent and marked changes in its shape - sometimes in just months.Moving into Puppis, as skies continued to be somewhat hazy, especially to the south and southeast, we looked at M47, a bright open cluster, and M46, another rich open cluster that also holds a ghostly round planetary nebula. A couple of return visits to Jupiter revealed a wealth of intricate detail in the many cloud bands, as the giant planet climbed higher in the sky. Finally, not long after the moon rose at 11:45, we took a look at the rich and very old open cluster M67 in Cancer - it suffered a bit from the haze and encroaching moonlight.The Moon, just 44% illuminated, still was shining at magnitude -9.9. That, combined with some persistent high thin clouds over the southern 2/3 of the sky, convinced everyone that it was time to call it a night. Even if we'd wanted to do some lunar observing, we'd have had to wait for it to clear the evergreen tree that sits to the dome's ENE. So we packed up and locked the gate at 1:05 AM. Returning home to Webster, MA well after 2:30 AM, Doug found completely clear skies, but a much colder air temperature - so he resisted the urge to do any more observing this night!-Doug Stewart---------------------------Once again, Doug wrote up our log as Les was teaching in the Nature Center. Thanks Doug! The class entitled Telescopes and Optics discussed how our primary astronomical tool works. Students learned how both mirrors and lenses focus light. Les broke out a bunch of "stick models" of various types of telescope mounts including a "fishing pole" mount where the objective is on the end of a long pole and is brought into columnation by guy wires. Unlikely as this rig sounds, it was actually created by a German astronomer in eighteenth century Leipzig. While the rig seems rediculous it actually solves the problem of chromatic aberation by using an extremely long focal length. -Les Coleman
