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Less faint, but still fuzzy

Having had such good luck with M74 the other night, I decided to try some more galaxies this morning, though not so faint - and this time I was very careful about my dark adaption.

The end result was that even though I was still using just the 5-inch Celestron NexStar, I found myself seeing everythng better than I can remember having seen it before. I think there are a combination of reasons for this -


  • I've been very careful about scope collimation
  • The Hyperion eyepieces I'm using give excellent contrast
  • My observation with the video camaera has given me a much better feel for what I should see
  • And, as mentioned, I paid more attention to dark adaption than I have been doing lately

Of these, the most unusual point is that business with video observing. Video observing can captivate you and for some it means leaving the eyepieces at home. But I find that the video images, while excellent, are, of course, not up to the standards we're used to seeing from Hubble and many large ground-based scopes these days. The gap between the pictures we're used to and what we see visually in our small telescopes is incrediby large. Enter the video camera. It's a big jump from visual observing, but still close enough to the visual experience so that you immediately see the connection between what the eyepiece reveals and what the camera reveals. The net result is, the video image becomes an excellent guide, suggesting what you should look for visually - and when you know what to look for it's simply easier to find.

That last, by the way, might be why many experienced observers are satisfied with what they see in a small - but high quality - refractor, while many newcomers to the hobby feel the only way to happiness is a bigger mirror or objective lens. Again, I am not ready to give up my 15-inch Obsession. You simply do see more with it. But skill and experience contribute much more to an enjoyable observing experience than the size of the scope. I'm learning that once more as I confine my observing for the moment to the 5-inch Celestron SCT. And I'm confident that when I switch back to the Obsession and turn it on these same targets that I'll see more, not simply because the 15-inch gathers so muchmroe light, but because using the five-inch has sharpened my observing skills.

As for dark adaption, I started my observing thismorning at 2 am, having had five hours sleep. When I got up the first thing I did - before turning on a light - was put on a pair of red goggles. Big help. This meant that when i stepped outside it seemed so light I thought for a moment I had lost track of what phase the moon was in - but there was no moon, though some high thin clouds did add to the lightness of the night by reflecting local light pollution. But the main thing is, my eyes were already there. With nothing to do in the observatory except punch in the time and date for the scope which had been in hibernate mode, I didn't even turn on the usual red light. But the high clouds did give me trouble at first.

When I went to M65 I could barely detect it and its companion M66. These are both bright as galaxies go, so I decided instead to focus on Algieba (gamma Leo) , a nice double. I figured the air would be pretty steady and it was - to the point that I actually could use a 3.5mm eyepiece, though the view wasn't all that great. This gives 338X, which on a five-inch scope is simply too much. Still, I could make out two or three nice diffraction rings around each of the bright components. I see these stars as a light, straw-yellow for the primary, with a greenish tinge to the secondary. Checking Sissy Haas' double star book when I got in, I found others detect roughly the same colors. For the record, the double looked better with an 8 mm and I could just split it with a 21mm (60X).

When I finished with these, though, I stuck my head out the dome and noticed it was really clear in the north with all stars in the Little Dipper visible at a glance. I figure under those conditions I'm approaching magnitude 5.5 skies which is about as good as it gets here. So I went back to galaxy hunting with the 21 mm Hyperion eyepiece and immediately zeroed in on M51, my favorite. It was looking better than normal, so I tried the much more challenging M101. Oh boy! Even looking quite casually I felt I could see more of it than I have seen before. I know it's huge and it appeared to be. I felt I could catch glimpses of it nearly taking up half the field of view. That pretty much matches the size Stephen O'Meara gives it in his book on the Messier objects - about 28' across. (The fov with the 21mm is about 68 minutes.)

But I wanted to get back to my original targets for the night - the Leo crew - M65 and M66, with their fainter companion, NGC 3628. I have to say, I feel satisfied simply seeing something that's 40 million light years away. I still can't imagine making the detailed drawings of it that O'Meara does. Yes, his skies are significantly better - but the key isn't his skies, it's his patience. Faintness I get - I feel I can see things - but the fuzziness remains. That is, I can't observe the kind of detail that good visual observers report. So i still have plenty to learn.

One nice sidelight to observing M65-66: I confirmed that the new Hyperions really do give the 68 degree apparent field of view they claim. In this particular instance I was using the 13mm which on this scope should give 98X and about a 42' true fov. My quick sketch shows M65 near the edge of the fov, with M66 in the middle. Since there is 21' between the two, this fits nicely with a 42-minute fov. For the record, M65 also seemed brighter to me and when I checked O'Meara's book I found that he too saw it as half a magnitude brighter than M66, though he notes other observers disagree. (I had read this before observing, but had not remembered which was which, so i trust my notes from the observing session as not having been prejudiced by advance knowledge. )

O'Meara calls NGC 3628 the "vanishing nebula" because it gets more and more difficult to see as you increase power. Hey - I find it difficult to see at any power. For me there are three gradations of visual observing. First comes detection. That means I know it's there, but I know darned little about it's shape, or extent. "Seeing" it means I've gone beyond detection. Now I can tell you things likes it's shape, size, and whether or not it has a bright core, for example. the third stage is observing - something I still do too little of - and observing means I actually have been able to eek out some meaningful information about the structure of the object. NGC 3628 is definitely in the first category - I detected it.

That's one Leo trio. It resides down near the Lion's haunches. A slightly more challnging group is up closer to the Lion's head. The main players in this are M95, M96, and M105. But honestly, I don't know why M105 isn't called a "double galaxy" and I wonder why Messier didn't note it. What's I'm talking about is NGC 3384. It's only about 7 minutes northeast of M105 and to my eyes looks like a slightly dimmer, slightly smaller twin. It certainly deserves more attention then it seems to get. I was mroe cpativated by this pair than I was by M95-M96 - as a pair. I mean hey - we're talking about billions of stars here, in each little dim, fuzzy patch. What that should mean in terms of life-bearing planets and intelligent civilization is simply too mind-blowing to contemplate. What you see just isn't what you know you are looking at and it's damned dificult to make it mean even a tiny bit of what it means. Sites such as this should reduce you to a a squaihy pile of jelly. But they don't and the reason is, it's simply too difficult to make that leap from this tiny, dim glow int he telescope eyepice to a magnificent system, thousands of light years avross and containing billions of suns.

So i content myself with making little scracthe son a yellow note pad so i can check my observations against the charts and books. And in the i finalk analysis myobsewrvatiosn mean nothing - except to me. I feel incredibly privledged to be themember of a species, as dumbs as it is, that is slowly becoming aware of its environment - and even more slowly understanding how icnredibly huge and complex that environment is. Not all thatbad for abnunch of idiots who spend most of their time and energy and resourdes tyring to figure out how to kill one naother.

So back to the scope. Before I leave M105 I want to mention that I did see another companion galaxy off tot he west and between the two. This was really faint - just detectable - and was, I assume, NGC 3389. Sue French mentions it in "Celestial sampler" - ooops. She say it is east-south-east - I definitely drew it to the west. One of us is wrong, and I suspect it isn't Sue. Oh well - that's why I take notes!

I concluded the three-hour observing session - it was 30 degrees and I wa sgetting cold - by doing a quick tour of familiar objects. I just wanted ot se ehwo the swcope - and my eyes - and the skies - would perform on objects I view regularly. so I went to M3, M13, M92 and M97. Splendid! Of these, the tricky one was M97 and I could see the owl eyes. I continue to be amazed with what this modest scope can do!

Posted by Greg Stone at January 10, 2008 07:12 AM Comments? Please email me: gstone@umassd.edu

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