Wednesday, December 29, 1999

Observing at Montebello 12/29/99

Several observers met at Montebello Open Space Preserve last night to take advantage of the run of good weather we've been experiencing. The conditions, although a bit hazy, were decent enough to make it a worthwhile night...

Before astronomical dark, in fact, with glow from the sun still obvious in the west, M33 was an easy telescopic object. It was also fun to see Orion risen already as the sky darkened. Once the sun's glow subsided and the winter Milky Way became apparent, running from the back end of Cygnus through Auriga and on toward Orion and Gemini, several of us noticed a very bright band of zodiacal light. The band reached quite high into the sky. It is the first time in months that it has been so obvious.

Still, the night was rather bright and a bit hazy, although things did improve later in the evening. David Kingsley was there with the 7" Starmaster Oak Classic, Richard Ozer showed up with a beautifully built home made 10" Dob (the mirror gave truly beautiful images of M42... nice job Richard!), Kurt ( K brought an outstanding 16" truss tube Dob with a Pegasus mirror, and I shared my 10" f/5.6 Dob with the new "Bob Fies" coatings (primary and secondary) with Ken Head. Joining us with binoculars was first timer Jason Newquist.

Ken and I spent quite a bit of the evening looking in and around Fornax, since Montebello has a good southern horizon. Due to the sky brightness, and the smaller aperture scope than I usually use for deep sky nights.

I found the first object, NGC 1097, rather faint. Since it is a bright object, this meant limiting mag would probably not be all that great, but still, the object was there, and switching from the 20 Nagler to the 12 Nagler, some definite structure could be detected. This galaxy at first just appears to be elongated, which is pretty obvious. But with some higher power, even in the bright sky, hints of its two main arms seemed to show.

The next object was NGC 1201. This elliptical galaxy was two full magnitudes dimmer than 1097, but because it is also much smaller in angular size it was actually relatively easy to see. A mag 7.5 star 17' from the galaxy, and a chain of four stars nearby helped locate this object.

NGC1344, was next. This galaxy, as was 1201, is located below Cetus, in fact, below the eastward curve of the constellation Eradinus. The chains of stars that make up Eradinus were invaluable in locating many of these objects, in an otherwise star poor region of the sky. NGC 1344 is a largish elliptical galaxy, about 2/3rds the size of NGC 1097. At mag 11, its light is rather spread out, making the overall appearance of the object dim. Three stars, mag 9.5, 10 and 11, form a slightly curved line to the east of the galaxy, making a good landmark from which to confirm its location.

I should mention that while I observed these objects, Ken was finding them. Ken has been working at improving his star hopping skills, particularly in relating the view on screen (laptop computer running a planetarium program) to that in the sky. This was a very good night for Ken. He was literally walking from "landmark" star partterns, from star to star, to the location of the target object. In several instances last night, confirming the star patterns and "walking" to a location as described was the only way to have a chance at seeing some of the very dim objects.

The next targets were NGC 1371 and NGC 1385, both fitting in the field of the 20 Nagler. Bother galaxies appeared roundish/elliptical, with 1371 a bit larger and slightly brighter than 1385, but 1385 yielded some mottling when the magnification was bumped up with the 12 Nagler. It is always fun to see multiple galaxies in a field, and this was no exception.

Speaking of galaxy fields, Kurt had his scope pointed at the Fornax galaxy cluster. Five large bright galaxies were obvious in a field and one half view. A number of dimmer small galaxies were also in the field. Kurt's scope would also show some very interesting planetary nebulae during the evening. Perhaps he'll provide a list of observed objects too.

Ken and I moved dimmer in magnitude at this point, going to NGC 1425. This one was a challenge to find, but both Ken and I located it each using a different approach star hopping to it. The galaxy is mag 11.6, but it is a largish lenticular object, so its apparently bight magnitude (dimmed by a bright sky) was diminished by its size. Whereas the last few galaxies were all in the 2'x2' range on average, this one is about 6'x2.5'. What helps to locate it is a flattened "W" of stars, very noticeable about 35' north of the galaxy. When you find the "W", you can orient yourself to find 3 dim stars in a chain to the south. The galaxy sits just south of the chain by a minute or two, and its major axis in parallel to the chain of stars. This one is a nice find. Magnified with the 12 Nagler is seems to show some central brightening.

NGC 922 is a small galaxy listed at mag 12.5. It is in a star poor sky south of Cetus, just west of the Cetus/Eridanus border. A nice bright triangle of mag 8-9 stars is close by and provide an easy landmark to shoot for. This galaxy was tough to pick out. You literally had to know precisely where to look to have a chance to pick out the here-then-gone glow with averted vision. Magnification helped this one, by darkening the background enough to make it stand out a bit better. It is about 2'x1.5'. A little bonus in the area is a bright ESO galaxy, ESO497-4, which was barely visible by following a chain of stars from the bright triangle to the exact location. This one gives meaning to the acronym "FFN"...

We finished in Fornax with NGC 686. This one too was all but not there, being found only by it fortuitous position amidst three bright pairs of stars that all fit into the 20 Nagler field of view. I won't go on about this object, since it was detected, and not what I would term "observed"...

The last two available objects in Fornax on the list I am again working (the Herschel 2500) were too dim for Montebello's sky, so they will be left for better conditions.

On the Herschel list, we did one other object. NGC 2124 is in Lepus, below Orion. It was a tough object owing to its magnitude (13), and that it is in a rich eyepiece star field, which if difficult to star hop. Still, we bagged it, clearly noting it ghostly (almost not there) elongated shape (size 2.5'x0.5').

The observing session was relaxed, and unhurried. We also observed many regular bright objects such as M81/M82, M35, M1, M42/M43, M78, the Eskimo Nebula, M47, M46 and its planetary nebula, Thor's Helmet (NGC 2359) which showed remarkable detail, M97, M67, NGC 2903 in Leo, Sigma Orionis and others.

By moon rise, we'd had a very good night. Some scattered clouds had appeared over the last hour before moon rise, but everyone was satisfied with a nice night out. Winter observing is really great... properly dressed, one can spend 6 hours under the sky, and still get home for a good night's rest.

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