April 22, 2001 viewing

Last night I went out viewing with our local astronomy club's president-elect, Andrew Cooper. He's recently completed the construction on a home-made 18" Dob and, among other things, wanted to see how it compared to my Obsession. We had, collectively, almost 1 meter of aperture. High, thin (sometimes thick) clouds came in just before sunset so we headed for camp to cook up some dinner. I had my wife and daughter with me for a "camp over" - even though I wasn't planning on "camping". I got a good fire going and turned on the gas lantern - not typical activities for an evening of viewing. We planned on catching some Z's and then getting up around midnight or so to see what the clouds looked like. By the time we got through with dinner most of the sky was beginning to clear. We had periods of relatively clear skies, but the seeing was pretty poor. I'd rate the steadiness at 1 or 2 (out of 10). Even stars at zenith were bouncing in and out of clarity at times.

The 20" f/5 --->

<--- The 18" f/4.5

          Me posing in front of my scope goes here as soon as Andrew:
                1) uses the rest of roll of film in his camera
                2) develops the film
                3) scans the film (slides or print film - I don't know which)
                4) sends me the electronic image

Digital photography 1, film photography 0....

Andrew was clicking off objects in Ophiucus, Scorpius and Sagittarius and I was basically goofing off, waiting for Mars to get high enough in the sky so I could get a decent eyepiece projection image with the Mavica (see images below). I did learn from Andrew what a wonderful eyepiece the 12mm Nagler is. I'd really only used this eyepiece for higher magnification views of an object. But Andrew spent the entire night with this eyepiece and I used it most of the night.

NGC 5139, Omega Centauri in Centaurus was very high in the southern horizon, almost near the meridian. Even though the seeing was terrible, the view with the 12mm Nagler was spectacular - the entire field was packed full of stars.

NGC 5128, Centaurus A, in the 12 mm, filled 3/4th of the field of view. The central dust lane looked like a freeway. The stellar glow was a bit washed out, but apparent otherwise.

I spent a lot of time lost in Corvus - There are tons of (faint) galaxies in the imaginary triangle connecting theta virginis, beta corvi and Algorab (delta corvi). NGC 4802 looks similar to M104, but there is an 11th magnitude star (GCS 5538:1876) on the northern border (in my eyepiece) that is just as bright as the central core. The proximity of this star really gives the impression of a dust lane similar to M104. I think this is an optical illusion of the space between the star and the galaxy.

NGC 4782 and NGC 4783 are spiral galaxies nearby NGC 4802. These galaxies so close to each other that they look like a double helix or a figure eight. The 12mm Nagler did a good job of bringing out the faint fringes of the galaxies.

NGC 4361, the planetary nebula in Corvus looks very much like M57, The Ring Nebula, but the central star is definitely much easier to view. This planetary is very easy to locate and takes magnification very well.

M104, The Sombrero Galaxy. The 12mm Nagler framed this galaxy perfectly, filling across the entire field. The dust lane was razor sharp. What a view. On a competitive not, Andrew's 18" gave a really good view of this (also with a 12mm Nagler) but the extra 2" of aperture of my Obsession really made a difference. peek.

Barnard 86 (B86), The Ink Spot, is my favorite "dark" nebulae. The 12mm Nagler was again a good choice for viewing this star cluster and associated dust cloud. The dust cloud looks as though a hole was punched through that portion of our galaxy. No star light can be seen in the center regions of this feature.

M17, The Swan (or Omega) Nebula shows as much structure as M42, The Great Orion Nebula. Again, the dark nebula and nearby reflection nebulosity are in stark contrast and each enhances the other. This nebula also takes magnification very well. An O-III filter helps to coax out some of the finer structural detail.

Andrew pointed out an asterism just north of the "stinger" of Scorpius. The asterism, 4 magnitude ~7 stars in a straight line, doesn't have a name that I know of. The northern-most star is next to an area of nebulosity, NGC 6357. An O-III filter help to bring out more of the nebula extending from the brighter region towards the center.

I spent the hazy parts of the evening looking through some 10x30 binoculars and really was amazed at how much can really be "seen" or more appropriately, detected: M13, M81, M82, Omega Centauri, Centaurus A, M8, M20, M17, M4, M6, etc. I may have to try for a binocular marathon certificate in the future.

I was able to get some halfway decent "thumbnail quality" images of Mars with the Mavica shooting through both the 22mm Panoptic and the 12mm Nagler. A polarizing filter set was used to cut down on the intensity, allowing some of the features to eek through. The 22mm Panoptic gives 134x magnification and the 12mm Nagler gives 246x magnification on the Obsession with the Paracorr. The Mavica was zoomed to about 6x to give an approximate total magnification of 800 and 1400 for the 22mm and 12mm, respective.


It's not Hubble quality, but then this is from a basic digital still camera looking through a telescope. Mare Erythraeum (8 o'clock), Chryse (6 o'clock) and Mare Acidalium (5 o'clock) can be discerned, along with the south polar cap (9 o'clock). Eyepiece projection using Obsession 20" and Televue 22mm Panoptic eyepiece. This image taken 0728 UT, May 27, 2001.	Eyepiece projection using Obsession 20" and Televue 12mm Nagler eyepiece. The Mare are much more pronounced, yes? This image taken 0830 UT, May 27, 2001.