Observing notes from Wednesday, March 13, 1996
As some of you already know, I've been working on a Dobsonian mount for the used Meade 10" Equatorial Starfinder telescope that I purchased. The equatorial mount for the scope is big, and heavy, and cumbersome. I would always have to dismantle it just to move it around the house and to get it out on the deck. So, I decided to build a Dobsonian mount so I could have easy setup. Well, I finally got the mount to a functional state, and it pulled out of "port" for it's first "see" trials. And good news, it is "see"worthy!!!
After attaching the last piece of Teflon for the altitude bearing, and securing the telescope in the tube box, I got the scope outside at about 10:30 p.m. Orion had already slipped behind the tall trees in the backyard (winter is fading fast). My first target was Castor, the double star in Gemini. I didn't really want to split the double, I was just checking the alignment and movement of the mount. Also, I wanted to zero in the new Telrad reflex finder that I have.
The mount works great. Although it's not perfect in its construction, it seemed to move smooth and easy. All the boards don't line up, and the scope doesn't exactly sit straight in the rocker, but none of this seems to interfere with the operation of the mount. I guess what they say about a Dobsonian mount being forgiving in the construction is true. The mount does exactly what I want it to, provide an easy to use and easy to set up observing platform. The one down side is that I built this thing out of ¾ inch plywood which is not light. But, it is a lot easier to handle than the equatorial mount. I was going to make some cosmetic cuts in it. I was going to cut off the corners and make angles like you see with some of the Orion and Meade Dobsonians. But with a square tube box, I don't think it would look all that great. I am going to cut some hand holds in it, but that's about it. After that, all's that left is to paint it.
As for the Telrad reflex finder, this is a great little invention. I definitely recommend this and any of it's cousins on the market. You see the sky through a non magnified window. Projected onto this, is three concentric circles forming a bull's eye (other similar devices project a little dot instead). This makes pointing the telescope a LOT easier. You don't have to worry about getting your eye all the way up to it, inverted images, or small fields of view. Again, I highly recommend this finder.
After zeroing everything in on Castor, I moved the scope to M35, the open cluster at the feet of the Twins. Many, many pinpoints of light burst forth in the eyepiece. Not as impressive to me as some of the other nearby clusters in Auriga, but striking none the less.
The springtime sky is kind of foreign to me, so I have to go after known targets. Next up was M44, the Beehive Cluster in Cancer. This is one of my favorite open clusters because it is so easy to see and find. It looks like a patch of nebulosity to the unaided eye. Binoculars will reveal a beautiful cluster, just "swarming" with stars. In the telescope, this is a glorious cluster. It has over 200 members. Although you see great detail with a telescope, I recommend viewing open clusters with binoculars. You really get the "galactic" feel, when you see the cluster of stars set against the field of the "regular" Milky Way stars.
Next up came the elongated, spiral galaxy, M108 in Ursa Major. This is a bright spiral galaxy, seen nearly edge-on. The sky was kind of hazy, had some light pollution, and clouds were starting to form a little so the view was less than perfect. None the less, the galaxy showed up remarkably well as a dim streak of light. M108 was added to Messier's catalog in 1954 based on his original notes. It is about one-tenth the mass of the Milky Way.
Next up was M97, the Owl Nebula, also in Ursa Major. At a size of 3.2 arc-minutes, this planetary nebular is an easy find for larger instruments. Glowing at magnitude 11.2, it's surface brightness is kind of low, so smaller instruments may have difficulty in finding it. It looks like a disk of gray-green light. I could see some irregular features in it, but could not discern the "owl" face.
Next up was galaxy, M109, again in Ursa Major. This galaxy is very close to the star Phecda in the bowl of the Big Dipper, which makes it easy to find. It looked like an elongated streak of light with a bright core.
Well, in keeping with my new tradition of trying to observe something new every time (or at least until I run out of easy objects to find), I grabbed my starchart to see what was lurking in the sky above. Since Leo the Lion was transiting the meridian, I decided to see what was there. My first "new" target in the giant feline was the galaxy M105. M105 basically appeared as a large fuzzy star. It is described as a round galaxy with a bright core, and that's how it looked. And of course, you can't look at M105 without looking at NGC3384, since they are only about 8 arc-minutes apart. It looks very similar to M105 through the eyepiece. I wonder why Messier didn't log this one.
Next up on the "new" list came the galaxy M96, also in Leo. M96 also looks like a round galaxy with a bright core. Photographs show it as a spiral. Right next to M96, is the galaxy M95 just 41 arc-minutes away. M95 is a barred galaxy and just hints at some structure in the eyepiece. Both M95 and M96 can be seen in the same field of view. I could also get NGC3384, M105, and M96 in the same field of view. It's quite an awesome sight to have three galaxies in the eyepiece view at once.
I also had some quick views from earlier in the evening. Just after sunset, I set up my 80mm refractor to show a neighbor a few celestial sights. Since it wasn't fully dark, and the @#$#$% house across the field had their floodlights on, the views left a lot to be desired. But, they did seem to impress him somewhat and I think I gave a good narration. We started out with Venus, since it is such a bright beacon in the western sky. The half-phase planet really shocked him and at first he thought the telescope wasn't focused properly. Next up was the open cluster Pleides in Taurus. He was really impressed to see so many stars in the eyepiece. Next came the Orion Nebula, M42. Not too impressive in the twilight, but the Trapezium entertained. Next up came the open cluster M41 in Canis Major. Again, lots of stars in the eyepiece. Then I quickly zoomed across the skies to my favorite cluster, the Double Cluster in Perseus (talk about lots of stars in the eyepiece!!!). I finished out the observing with some double stars. Fist came Mizar in Ursa Major, and easy double to see. Then came Polaris in Ursa Minor, with it's really dim companion. The night ended with some mythology, discussions of star sizes and systems, and of things to come (like Comet Hyakutake).
Jeffrey L. Polston
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