Log, Nov 24, 2000

61 visitors. (Les, our usual scribe, was out of town visiting with family. Joe steps in to write the log this week.)

"If you don't like the weather in Rhode Island, just wait a minute."

That aphorism proved its truth last night to the staff and visitors at FDO. The first staffers saw clear skies, and the promises of a clear night ahead. First in the scope was Jupiter so that we could see the end of a transit by one of its moons, Io. Despite its low position on the horizon, we were able to see the shadow finish its path across the gas giant, though Io itself was lost in the atmospheric murk.

The darkened skies beckoned with promises of deep sky wonders thanks to the absence of the moon's light, and we swung over to a couple of favorites, M15 and M2, both globular clusters that resolved well in the 16" scope.

A quick peek at the clusters M71 and Harvard 20 in Sagitta was taken as folks started to arrive for the evening, then we moved back to Jupiter and Saturn, always crown pleasers. By 8:00, a thin haze had started to thicken, obscuring some of the more subtle features of the planets, but still allowing observing. By 9:30, the haze had become so thick that only a handful of stars were visible. Betelgeuse and Rigel in the rising Orion became third magnitude stars, and only the sheer brightness of Jupiter and his moons punching through kept the scope open. Still, folks were showing up, and the staff's talk of shutting down and heading to warm beds kept getting postponed as we showed the murky view of gas giants to the newcomers.

At about 9:45, though, a look up through the dome's opening showed a few stars around Aldebaran, and a look up showed plenty of stars in Perseus in Cassiopeia. Auriga was also in the clear spot, so we swung over to our old favorite, M37, with the orange star in the center giving beautiful contrast to the swarm of bluish white stars around it. The seeing was still variable, though, and the view of M37 faded in and out. Doug suggested that Castor would be a good target, and he was right. The brightness of this double star punched through the haze well.

By 10:15, the haze had all but disappeared. It would be gone totally by 10:30, leaving us with a brilliantly clear, dark night with very little atmospheric turbulence to shake the seeing. The nights don't get much better than this!

With about 25 people now packed into the dome (!), we turned our attention to (where else?) M42. New and experienced observers alike were entranced by the view of the nebula with the Trapezium nestled in its heart.

Our next stop was M81 in Ursa Major. Despite the sky glow of the cities to the north, a little patient viewing and averted vision showed some of the spiral structure of this galaxy. Our next stop, of course, was M82. These two close galaxies can be seen in the same field of view with most telescopes, but not with the 16". No matter, the dust lanes in this galaxy were prominent, making for a fine sight. Our next stop was M97, the Owl nebula. Low magnification is the key to bringing out this object, and the use of the Oxy-III filter helped greatly.

With the filter in place, and tired of the breeze blowing in the dome from the north, we swung to the east for a look at NGC2392, the Eskimo nebula. This object withstood the high magnification of our 12 mm eyepiece well, aided by the filter, and the outer "fringe" of the nebula was distinct from the brighter core. Then it was back to M42 for a look with the Oxy-III filter, which showed a delicate fog extending much further to the left than is seen without the filter.

By now, the cold had driven most visitors away except for a couple of folks who were themselves amateur astronomers. With Orion high in the crystal sky, we decided to try for that most elusive of targets, the Horsehead Nebula. Off came the Oxy-III filter, and on went the Hydrogen Beta. Unsure of the size of the object, the initial view was difficult. Off went the red lights and computer monitor, making the dome as dark as possible. As our eyes became even more adapted to the dark, the division between the faint nebula IC434 and the sky became distinct, and there it was! Larger than I'd expected in the 40 mm eyepiece, it was a dark patch against the background nebula best seen with averted vision. It entered the background nebula from the right and curved up. Doug confirmed my observation, and only then did we compare our views with the chart in Skymap Pro. We'd gotten it exactly. Everyone left eventually saw the Horsehead, a first for each of us.

We finished up with a rather quick tour of a few favorites. First was M93, an open cluster in Puppis, followed by M46, an open cluster with a beautiful planetary nebula in the field. Nearby, the open cluster M47 was very nice, with a lovely double star at its heart.

I'd remembered that we'd "discovered" a very nice cluster last year in Canis Major, but I couldn't remember its designation offhand, so we used the LX200's GOTO function to great advantage. As Doug read off the NGC numbers of open clusters listed in Burnham's, I pointed the scope to each object in turn. The third try was the charm; NGC2362 was immediately recognized as our old friend. A triangular open cluster with the 4th magnitude star Tau Canis Major in it, this is a beauty.

As the cold and fatigue set in (it was closing in on 2 AM by this point), a few more targets were chosen. NGC2217, a very small galaxy, was a candidate for our "smudge of the week," but after a few moments, it was decided that it was too pretty to earn the title, so there was no "smudge of the week" awarded this time out! M79, the small globular in Lepus was next. It was a bit brighter than last week, and though still small, we resolved a number of stars.

As a final object, Doug suggested Hind's Crimson Star, also known as R Leporis. This star is a long period variable that ranges from 6th to 11th magnitude. We estimated it at around 9th magnitude. The color of this star is extraordinary. It glows with a deep red unlike any other star I've seen.

Though the sky was willing, we'd gotten to the point where the prospect of a warm bed called to us louder than the skies, so at 2:15, the doors were locked and we were on our way home. We were very happy that we did not make a hasty decision to leave at 9:30!

(An addendum by Doug).

Following up on Joe's excellent log report for last night, I must say that I can't recall an evening where the weather played as many tricks on us! There have been times when it was nice and then went down hill; or times when it was poor and then improved; but to have swung full circle from very nice to awful then back to marvelous was quite an experience! Only the bone chilling cold (low 20's by the time we closed up) kept it from being a perfect night. At least the wind was much reduced from the night of the Leonids! Speaking of which, we saw quite a few stragglers from that shower last night. One brilliant one (at least magnitude -4) had a remarkable blue head and a scintillating white trail as it streaked some 40 degrees from the east to the southwest. It was crowded in the dome at the time, but several of us spotted this dazzler.

The highlight of the night, of course, at least for we seasoned observers, was the Horsehead Nebula. As the sky cleared around 10:30 or so, and with Orion rising high into a moon less sky, Joe and I knew that this would be one of out better chances of the winter to spot this very elusive target. Ernie had told us previously that he'd seen it in his 6" wide field Newtonian and a nebular filter, so we approached the challenge with some optimism. What threw us off in our initial views was the size of the object - easily 1/5 of the field of view in the 40 mm Konig. The Hydrogen Beta filter provided just enough contrast to outline - dimly - the horse's famous head shape. As is our practice from other tough objects, Joe and I confirmed each others' views prior to consulting SkyMap Pro for confirmation against the star field. Most long exposure photos you see of the Horsehead make it appear much smaller than it actually is - showing sky all the way from bright Zeta Orionis down to Sigma Orionis (the noted quadruple system we observed last week). It was a rewarding experience for me to have finally spotted the nebula, after many many attempts with other scopes over the past four decades. Barry and Tom also confirmed the view, although they may have been a bit under impressed by its overall dimness and low contrast. It is easy to understand how this object may be seen in smaller scopes with their wider field of view - contrast may be more enhanced. I will try it again with my C8 and narrow band nebular filter, using last night's experience as a guide. Now what more difficult challenges lie ahead?

Many thanks to Joe and Doug for filling in for me (Les) as I took my portable scope up to a family reunion. Yes indeed, Vermont has skies to rival ours but its a wee bit of a drive!

-Joe Harley, Doug Stewart

Leslie Coleman
Leslie Coleman
Entry Date:
Nov 24, 2000
Published Under:
Leslie Coleman's Log
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