55 people. Well our old friends the Big Apple Circus paid us our yearly visit this week. I had exepected they would open tonight, but they actually will be open Monday through next weekend. Most astronomers grouse [unless the rant, rave and froth at the mouth] about light pollution. Certainly having a highly lighted three ring circus tent a quarter mile away is not like being at Cerra Parranal during a power failure. However the FDO astronmers are very happy to have these folks visit us each year. The Big Apple Circus is a major source of the revenues which keep Ninigret Park alive and well. Without the park we'd be out of business.

Despite a 98% illuminated moon blazing at magnitude -12.3, the night went quite well at FDO, with lots of inquisitive visitors, many from the Big Apple Circus staff, who have been setting up for opening day on Monday. Some of the guests were repeaters - notably a couple who drove down from Storrs Connecticut and stayed until 1 AM. The fellow had been with us a couple of previous times, once last fall with his homemade refractor, which was constructed out of an old 6" Air Force aerial reconnaissance lens mounted on an unusual wooden frame. There was also a couple who claimed that they had driven all the way up from New Jersey just to view Mars! Unfortunately, the air was very unstable last night, despite the clear skies. Even the moon looked like it was being viewed through an aquarium!

Joe began the evening by doing a realignment of the scope. We've had an unfortunate series of power outages in recent weeks, each one forcing us to realign things. Once under way, experienced observers in attendance were able to pick out quite a lot of detail on the surface of Mars when the air briefly settled down, but Doug thought that most folks were disappointed in the overall view. This has been the pattern with Mars for this entire apparition - it is just too low along the ecliptic for observers at our northern latitudes. Combining this with the poor weather we've had has made for very frustrating viewing experience. The 16" scope, actually as a result of its superior resolving power, often enhances the views of the atmospheric turbulence! There were times when we may have done just as well or better by stopping down the aperture. (For the great opposition of August 2003, at least Mars will be 13 degrees of so higher in Aquarius.) Using blue and yellow filters last night some of us, especially Ernie, our resident Mars expert, were able to discern lots of features, especially the south polar cap and the bright Hellas region, among others.

Despite the unstable seeing, many folks nonetheless got their first looks ever through a telescope at Mars, Neptune and Uranus. We also showed several globulars, notably M19 and M10 in Ophiucus and M22 in Sagittarius. Despite the bright skies, these fine objects were interesting to view. With such a bright background it seemed easier to see the overall shape of these globulars. On dark nights they are so rich and dazzling that you often don't notice shapes or areas of heavy star concentrations. In M22 particularly, several of us commented on the knots of star concentrations which are usually lost in the glow of thousands of dim stars. One particularly rich area on the SW corner of the globular stood out, as did many bright foreground stars which were obviously not cluster members.

Les and Art had spent quite some time outside the dome with the crowds, doing their informative constellation talks. A spectacular close pass of two satellites going in opposite directions occurred early in the evening. A predicted substantial Iridium flare at about 10:35 turned out to be a total waste of time. We saw something but it wasn't mutch.

After coming inside to spell Joe at the eyepiece of the 16" Les spent some time with folks looking at M8, the Lagoon Nebula. Even in the washed out skies this fine object had plenty to show! It does, after all, surround the fine open cluster NGC 6530, which has at least 25 bright members. The Lagoon nebulosity was vaguely visible when we used low power eyepieces, but nothing like the wonderful views we get on dark nights with the 16."

Just for fun we looked at M17, the Omega - or Swan - Nebula. Those of us who had seen it before quickly picked out its distinctive shape, even in the glare, but again this was nothing much to show to visitors. As Doug commented, "THE SMUDGE OF THE WEEK honors went to the Omega. You can easily tell what that moon was doing to our viewing!" In spite of this we managed quite a few objects that were all viewed satisfactorily, despite the bright moonlight.

Around 12:30 Doug took a walk outside the dome with my binoculars to look for Comet Linear A2 2001, as Pegasus had already risen well above the eastern horizon (where oh where are these seasons going!). A quick glance at the circlet of stars forming the head of Pisces, just below the square of Pegasus, and the comet jumped into view! It is easily 4th magnitude or so, although these things are tough to estimate in bright moonlight. Everyone still present observed it easily in binoculars and then we turned the 16" on it. What we forgot to do, however, was to remove the polarizing filter from the 40mm eyepiece. We had been using it for lunar observing. Needless to say, this resulted in a rather underwhelming view of the comet! We didn't realize our error until later on when putting the gear away, but in all honesty there would have been little more to see in the brilliant moonlight.

While in the area of Linear (same 100x field of view) Dave and Doug spotted an interesting double star that caused us to do some checking. (The star is Tycho 591-1742-1, HD 221272). Zooming in on it in SkyMap revealed a third member, about 10th magnitude, lying between the two brighter primaries of magnitude 7.8 and 8.3. Dave thought that he saw it at first, but Doug could find no trace of it at powers up to 340X. It turns out that in the Hipparchos notes for this star there is a strong likelihood that this 3rd member is misplotted! At least my eyes weren't failing me at the late hour! We will certainly view this object again to verify what's really there.

A pleasant surprise was Comet Linear. Doug first spotted it in his binoculars at about 12:30. It was an easy object, very bright and oval shaped, although he couldn't discern a tail due to the bright moon. We swung the 16" over to it and were underimpressed, only to realize later that we had left the polarizing filter in the 40mm eyepiece! The moon was overpowering by this time. We will all want to check out this comet once the moon has cleared the area!

By 1:30 the air had grown quite chilly, and despite the clear skies the moon was more dazzling than ever, so Dave and Doug decided to put our fired up astro interest aside and head home - we both have long drives. Next weekend the Big Apple Circus will be in full swing, so we will have to contend with that, but at least the moon will be retreating, just past last quarter. We locked up and left the park at 1:50.

-Les Coleman

Author:

Leslie Coleman

Entry Date:

Jul 6, 2001

Published Under:

Leslie Coleman's Log