Orwell Astronomical Society (Ipswich)
Miscellaneous Observations, February - March 1986
The first two Wednesday evenings in February 1986 were clear and, not having seen those faint points of light in the night sky for some time (stars, I seem to remember they are called...), members of the Nebula and Faint Objects Section of OASI eagerly unlocked the door to the dome of Orwell Park Observatory on the night of 19 February. Having removed the covers from the 26 cm refractor, opened the shutter, made the decision to look first at the Orion Nebula, pointed the telescope in roughly the right direction (one develops the knack of finding objects through the mahogany and copper skin of the dome!), the members present awaited the final positioning of the dome shutter over the end of the telescope in order to provide a view of M42...
But, instead of the usual rumble of the rotating dome mingling with the grunts of exertion from the lucky person turning it, there was a loud clunk followed by numerous expletives: it won't budge!, ****!!! Following an in-depth scientific investigation (which took all of two minutes) we theorised that the dome must be frozen solid (February 1986 had been a little on the chilly side). Experimental verification was required and therefore several people inspected the drain gutter on the observatory wall. It did not take long to gather, sift, correlate and corroborate the available data and to issue a preliminary report summarised as: the drain is full of ice and the skirt is frozen in position!! You can imagine the frustration, gloom and despair that settled on the group. We sadly closed the shutter, diligently replaced telescope covers and closed and locked the door to the dome. After huddling around the electric fire in the club room with occasional mumblings about It's never happened before, not even in 1979!, we decided that the only possible course of action was to retire gracefully to the Ship Inn.
On the following Wednesday evening (26 February) we were blessed with a second clear night! Of course after the weather that we had endured ever since the return of Halley's Comet, the word clear has to be interpreted liberally. If third magnitude stars can he seen without optical aid one tends to think of it as a good night. On this particular good night, there was hazy cloud with interference from the gibbous Moon. However we once again eagerly unlocked the dome door hoping for a glimpse of at least some of the brighter nebulae. The dome wouldn't still be frozen solid would it? After all, the snow had been thawing in the sunshine of the day. This time we decided to try turning the dome first. Once again we heard the fateful clunk as the slack in the keyways, bearing and rack and pinion of the dome rotation mechanism was taken up - but there was no rotation! After various comments, curses and mutterings Martin Cook decided that direct action was required and fetched the fan heater from the club room. We played the heater around the base of the dome in the region where most of the remaining ice appeared to lie while two members tried to turn the dome wheel. Nobody present believed that this would work but individuals like Martin, with such a lengthy history of practical observatory maintenance, have to be humoured. After surprisingly few minutes of this treatment the dome turned! The problem then became, having got the dome moving, did we dare stop? We decided that if we kept the dome moving with the heat source removed we might wear a track in the ice as it refroze. An improbable theory but it worked, enabling us to position the dome at will!
We removed the telescope covers, opened the dome shutter, positioned the telescope once again for M42 and rotated the dome to the appropriate position. After final positioning of the telescope, there it was in the eyepiece, the Orion Nebula glowing faintly through the hazy cloud that had by now thickened somewhat.
Before the thickening haze obliterated everything we tried to observe M46 in Puppis. After appropriate repositioning of the dome (still turning) and telescope, followed by several minutes searching and consulting star maps, we found it. We could see only the brighter stars of the cluster and could not discern at all the embedded planetary nebula; the view, in fact, was totally unimpressive. We then moved 1.5° west and found M47. We could discern the bright stars of the cluster glowing through the mist; however, the fainter stars were invisible. The haze, Felixstowe dock lights and the Moon had beaten us again! Once again, after closing the observatory the only thing to do was retire to the Ship Inn.
On the evening of Wednesday 05 March there was another clear sky, the third in succession! And the evening was a good one: we could see 4th magnitude stars with the naked eye in the early part of the evening. And, as this was the week of the thaw following the big freeze, there was no chance of a frozen dome.
After opening the dome we went straight for M46. Although the seeing was much better than the previous week it was still not ideal and the planetary nebula embedded in M46 was very difficult. This was mainly due to the mist rising over the River Orwell rather than the hazy cloud of the previous week. After a quick look at the Orion Nebula, M42, we decided to move further north where the skies were becoming much clearer (5th magnitude stars were visible to the naked eye).
Next stop was M65 and M66 in Leo, two moderately bright spiral galaxies only 0.5° apart making a fine pair together in the 26 cm refractor using a low power eyepiece. Two fairly easy NGC objects close to M65 and M66 were next on the list: NGC 3628, an edge-on spiral forming a triangle just over 0.5° to the north, and NGC 3593, another edge-on spiral lying less than 1° almost directly to the west. By now the seeing was excellent (better than anything we had experienced for several months).
Next on the agenda was a quick look at the Beehive Cluster, M44, in Cancer. It was an easy naked eye object and a spectacular sight in binoculars. Unfortunately because of the somewhat restricted field of view, it is not a particularly spectacular object in the 26 cm refractor. We moved on towards the zenith and one of the most rewarding sights of the whole evening, the Whirlpool Galaxy, M51. We could see a definite spiral structure and even discern a hint of the spiral arm crossing over to the satellite galaxy NGC 5195. After everyone present had feasted their eyes on this object we completed the evening's observations with views of M81 and M82 in Ursa Major. These appeared as very bright objects with M81 filling almost half the field of view in the 26 cm refractor while M82 was spectacular with some of its irregular dust lanes clearly visible.
After one of the best Wednesday evenings at Orwell Park Observatory for a long time we were too late to visit the Ship Inn but all present agreed that our sacrifice was well worth it!
David Payne