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![]() This is another fragment of the observing report for the evening of March 19-20, which fortunately was clear here in Cincinnati. The sky was about Mag 5.5 at zenith I would g uess, at Stonelick State Park, about 30 miles east of Cincinnati, where my club, FOTO, has its observing sessions. There were a dozen or more scopes there, including my 11 inch Dob, a 10 inch Dob, a 5 inch LOMO MakCass, at least one Nextstar 8, Wally's 25 Obsession, and the new club scope, a 16 Dob made from a kit and using a Meade 16 inch mirror. I wasn't particularly interested in marathoning, since it was getting cold and windy, and my main interest was in the Virgo cluster of galaxies, which I hadn't seen in about 5 years owing to the pressure of work, and bad weather conflicting with new moon nights. I remembered seeing several galaxies in the same field (multiple objects in the same field is one of my interests) with my venerable Telescopics 6 inch f.5 and I wanted to see what my new 11 inch Dob would do. I feel familiar with most of the sky with the exception of the Coma-Virgo cluster and I wondered how to explore it. There are all kinds of guides to exploring it, in Burnham, S&T (I recently learned of a fine 1994 article by Alan MacRobert, whom I respect both as an observer and as an inspiring writer, but I didn't have a chance to dig out the article. About a year ago I posted here a review of a charming article In Amateur Astronomy by a British amateur who used Denebola as a starting point, waited something like 23 minutes, and found the scope was in the heart of the cluster. I didn't want to spend the time and I was unsure of the right amount of minutes to wait. I noticed that a majority of the articles say, start with fifth magnitude 6 Comae, which is in between Vindemiatrix and Denebola. I have always experienced this star as very hard to find, and indeed it was not visible early this night as Virgo rose from the horizon. Only Vindemiatrix and Porrima were visible in virgo. Guessing he halfway point between Denebola and Vindemiatrix has never worked for me either, perhaps because the skies were too hazy and I was trying to far into the summer. I had just read Sue French's fine article on Markarian's Chain, in the May issue of Sky & Telescope, and I had heard a lot about it and had seem pictures of it, so I wanted to start there. Fortunately I had Sky Commander (one of the wisest purchase I ever made, since i am an urban observer) on the 11 inch Dob so I aligned it on Polaris and Aldebaran and zeroed in on M84. It and M86 were soon in the eyepiece, bright as could be. But I couldn't find the rest of the Chain. Referring to SA2000 which I had with me, it looked like I should look east of the M84-M86 pair, but that didn't work. I am a great believer in asking for help if you can't figure something out for yourself with respect to finding an object. (I make up for this b y showing others the sky, which I did later in this evening, and by being able to easily teach anyone anything I understand myself). So, I moseyed over to Wally and the 25 inch Dob and asked him if he could show me how to find it. He could, and perched high in the sky on the ladder, I saw the Face of five galaxies, the Eyes--too more galaxies --and two additional galaxies beyond the Eyes, and then two additional galaxies in a line beyond that. I had followed Markarian's Chain. Several other observers came over to look at it --bright and impressive in the 25 -- so a whole group of us became familiar with it, thanks to Wally, I tend to remember exactly who showed me how to find certain objects I couldn't at first find myself, including M27, M5, the Bug Nebula, and the Helix for example (the last two are owing to Scott Naylor, known as "go-to" in our observing group), so Wally's name will go on the list. Back at my own scope I realized what my difficulty had been: In SA 2000, M84 and 86 are side by side laterally, but since Virgo was just rising at Stonelick, 84 was above 86, so I had to move the scope south, rather than eastward as the Atlas would suggest. I was able to trace out the Chain in my own scope and show it to others, which I found gratifying. Wally had an 80 mm Shorttube mounted as a finder on the 25. Since I had been thinking of getting a 25, I asked him what he thought of it. He said, it's a great finder but I wouldn't want to use it as a telescope. I did learn from him and from Scott Naylor how they find Markarian's Chain. They start with 6 Comae all right, but how do they find 6 Comae? They look for a T shaped asterism in the finder. At the west end of the crossbar of the T is 6 Comae. Very near 6 Comae is M99. At the other end of the crossbar of the T is another star (there is one in the middle too) and near that is M100. If one follows the shaft of the T southward, it curves West, and M98 is right there. But if you follow the curve down but when it curves west, you curve east, you get to M84 and then M86. I had never heard of this procedure before and for starhopping it seems an ideal way to begin exploring the Virgo-Coma cluster. From that spot I was able to starhop to M88 and M85, a bright spiral and a bright elliptical. I have starhopped for so many years I break into it involuntarily, even though I now have Sky Commander, which I used to find M64 and M104. I found also what was probably M49 but I wasn't sure. What I should have done was set Sky Commander to the "search and identify" mode and it could have told me what I was looking at, but I didn't know how to use it that evening. Another possibility would have been to enter M49 into the display and see if the digital readouts were zeroed out. But I didn't think of that either. The adage I heard recently is that it takes 6 months to get used to using a new scope and I have found this to be true. I also looked at M63, 94 and 51 and was impressed by how much more detail in galaxies was visible at 115 x (12 Nagler) than at 70x (20 mm Nagler). People were amazed by the detail in the M51 and NGC 5198 duo, with spiral arms and the link between the two being obvious. M63 was very clearly a spiral, in a different orientation. I was delighted with the high contrast images of the 11 inch scope. I also took the opportunity to look at galaxies with the club's 16 inch Dob, and I can tell you for sure that a 16 inch mirror of decent quality will greatly outperform a superb 11 inch mirror on galaxies, as you might expect. But I have no chance of ever being able to lift, transport, or set up, a 16 inch Dob. A lot of people have posted here that the DeLuxe Laminated edtion of SA2000 Revised is too big and awakward to use at the scope, it is better used at home. I also own the DeLuxe unlaminated editon (I am a star atlas junkie), well worn with use, so I brought that instead. Mistake. The strong winds blew the pages abo ut and blew the inserts across the observing field, where they had to be retrieved. The much heavier pages of the laminated edition would have served much better, and that is what I shall bring next time. It got colder and colder, and windier and windier, so the last few holdouts, I among them, packed up at 2:30. A most enjoyable session. Ciao, Bill Meyers |
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Correction: the companion linked to M51 is NGC 5195, not 5198, which is
nearby but is much fainter and not directly linked to M51. I didn't notice 5198. Bill Meyers Bill Meyers wrote: (snip) |
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Bill Meyers posted:
I noticed that a majority of the articles say, start with fifth magnitude 6 Comae, which is in between Vindemiatrix and Denebola. Actually, to me the Telrad offers the simplest method of hitting the center of the Realm of the Galaxies (as the Markarian Chain area was once known as). Place the center of the Telrad reticle exactly halfway between Denebola and Vindemiatrix (Epsilon Virginis). Look in the scope, and you should be centered on M84. From there, I usually go "galaxy hopping". Clear skies to you. -- David W. Knisely Prairie Astronomy Club: http://www.prairieastronomyclub.org Hyde Memorial Observatory: http://www.hydeobservatory.info/ ********************************************** * Attend the 11th Annual NEBRASKA STAR PARTY * * July 18-23, 2004, Merritt Reservoir * * http://www.NebraskaStarParty.org * ********************************************** |
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Hello, David,
"Dead center, Tennessee!" You obviously use the Telrad well. I used to try that, pointing the scope to the midpoint between Vindemiatrix and Denebola, not knowing actually that I should be seeing M84, but I had no luck, I didn't see anything. I think the haze and the light pollution used to get in the way, or perhaps my aim was off. . I'll give the Telrad method a try again, just to see what happens. To me, the Telrad, the Sky Commander, and the Dob itself, and of course the Nagler 82 degree eyepieces, are all new-fangled technology, but I find it really pays to adapt to new technology. I like the Telrad a lot and have used one (actually two, one on each scope) for years, but as I grow older I find it harder and harder to crouch to peer through it, despite the Telrad's huge eye relief, if the object is at all high in the sky. I found the green laser finder obviated crouching entirely, but I could only use it when observing alone, for fear of spoiling the aesthetic of the sky when observing with others. But now that I have Sky Commander, the green laser pointer is no longer needed. The march of technology continues. My prediction is that go-to will eventually become standard on almost all scopes, but I am a bit ambivalent about it since it may make the telescope seem robotic rather than something I am involved with. Using DSC's at least involves some precision in getting as close as possible to a fully zero reading on both altitude and azimuth. Clear skies, Bill Meyers David Knisely wrote: Bill Meyers posted: I noticed that a majority of the articles say, start with fifth magnitude 6 Comae, which is in between Vindemiatrix and Denebola. Actually, to me the Telrad offers the simplest method of hitting the center of the Realm of the Galaxies (as the Markarian Chain area was once known as). Place the center of the Telrad reticle exactly halfway between Denebola and Vindemiatrix (Epsilon Virginis). Look in the scope, and you should be centered on M84. From there, I usually go "galaxy hopping". Clear skies to you. -- David W. Knisely Prairie Astronomy Club: http://www.prairieastronomyclub.org Hyde Memorial Observatory: http://www.hydeobservatory.info/ ********************************************** * Attend the 11th Annual NEBRASKA STAR PARTY * * July 18-23, 2004, Merritt Reservoir * * http://www.NebraskaStarParty.org * ********************************************** |
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