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Archive for the ‘Learning’ Category

Insomnia – I am making some progress on it, but not much, but when I woke up at 1:30 am this morning I at least could see stars. We have had a pretty steady dose of mostly cloudy, hazy, foggy, partly cloud and heavy rains lately – 7 inches one day, five inches more a few days later and about an  inch yesterday  – so clear skies have been unusual and don’t last long.

These clear skies lasted long enough for me to get the 66mm  WO scope out and after a false start – batteries are weak on the Celestron mount I suspect – I got it on the Desert Sky dual mount/Bogen tripod and had a good time with some old friends.

I actually have a little plan in mind – to establish a list of best objects for popular consumption on any given night – or more accurately, any given sidereal/star time – of the year.  My goal would be for these objects to be nice in any scope, so if they’re nice in the 66mm you can be pretty sure they’ll be nice in anything larger.  The 66mm thus establishes a base line. So my observations were made with this in mind.

Yes, I’m pretty sure I could make such a list from memory – but I would trust it more if I check each object with this in mind.

So – up for starters was, of course, Albireo. It did fine at 16X – was really pristine – but I think the newcomer would appreciate it more at 30X. Once they were certain what they were seeing, they could try backing off some.

I have a soft spot for Albireo, but I closed this session wilth Almach and I have to say that although it was pretty low in the east at this time, I still find its colors richer than Albireo. It does take significantly more power. I found it best at 78x, though it could certainly be split with less.

There’s no contest with the Dragon’s Eyes – they are a perfectly matched pair that’s pretty easy to split in binoculars and certainly split easily at 16X, but seem better framed at 30X.

Meanwhile the Dolphin presents more of a challenge. Gamma Delphini is a sort of pale version of Albireo – in fact I would have a sliding scale of intensity for blue and gold stars where I would rank Almach the most intense, then Albireo, and then Gamma Delphini. Needed about 50X to get a decent split and it was better at 79X.

I liked M13 at all powers from 16X to 79X – but it was best at 79X because at that point I could really see individual stars flashing across the main body of this star ball.

M31 was another object that did fine at all powers, though it was easier to pick out M32 at 79X.

As I think – and write – about this experience I basic process for visitors pops into my mind. I want to start them witht he naked eye view. From there, I’ll move them to low power binoculars on amount – just to let them know what they can expect to see with their own binoculars.  Next up would be the 66mm at 16X and on a tracking mount, tobe followed by the 5-inch SCT on tracking mount a with a 24-8 zoom. Finally they could go in the observatory and use the 8-inch SCT,

Last step? Show them a good image  – probably in the observatory and under red light –  of what they’ve been looking at and encourage them to go back and look again.

And in this process define a “glance” as one minute at the scope – a “look” as three minutes or more.

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I’m starting a new  a “Star Hopper”  education program for anyone who wants to learn about telescopes and how to find their way around the night sky with or without a computer. It will be run out of “Driftway Observatory”  – my backyard in Westport, MA, so obviously you need to be in driving distance and participation on any given night will be limited.  The way this works is invitations are sent out to the email list of participants on the morning of a night when the forecast is favorable.  Participants can then respond and space is reserved on a first come, first served basis.

You can use your own telescope, or use one of the telescopes here.

I see this also as an excellent parent/child shared learning opportunity, however, each child must be accompanied by an adult – one child/one adult, two children/two adults.

Other requirements for participants are:

1. That you purchase a copy of the excellent guidebook,  “Turn Left at Orion, ” which we will use for every observing session.

2. That before you attend any night observing session you complete a day-time workshop on telescope use in general, but particularly on the new line-up of telescopes at Driftway Observatory. 

3. That you have – or purchase – a pair of handheld binoculars suitable for exploring the night sky. 

The learning goals of this program are simple:

1. Learn your way around the night sky using the unaided eye and binoculars. (My “Prime Time” web site will be a major resource for this.)

2. Learn your way around the universe by finding examples of the major classes of astronomical objects (double stars, open clusters, globular clusters, nebulae, galaxies, etc.) with one of the telescopes at Driftway, or your own telescope if you have one and wish to use it instead. 

3.  Apply the classic advice of Sherlock Holmes – learn to “observe,” not simply to “see.”

My role will be to suggest appropriate targets (from “Turn Left at Orion”), have telescopes and large binoculars available for you to use, and coach you in their use.  Your role will be to read about your targets and how to find them before coming out to observe. You will find yourself involved in setting up instruments, using them, and putting them away when done. Most importantly, though, you will find objects on your own with some direction from me.

I hope you will find this approach very satisfying, but I’m not sure this style of learning is appropriate for everyone. You’ll have to decide if this is what and how you want to learn. If this interests you, please respond by sending me  email ASAP and ask to be added to the Star Hoppers list. If you know someone else who might be interested, please have him/her contact me.

I will schedule appropriate times for one or more persons to come here to learn about the telescopes in daylight. We will be using the three most popular types of astronomical telescopes – all relatively inexpensive models, by the way: A 12-inch Dobsonian (simple manual control), a 4-inch refractor on an Equatorial mount (mostly manual), and a 6-inch computerized, “go-to” catadioptric.   If you master those, I’ll be happy to show you how to do astronomical video as well.

You can find a copy of “Turn Left at Orion” at a local bookstore – Barnes and Noble has had it in stock – or at an online store, such as Amazon.com.  One caution. There are still several editions of this book available.  If you have an older one, that’s fine, otherwise get the most recent one (fourth edition 2011), and I suggest the spiral bound one because it folds flat and is easier to use in the field. Here’s the complete title of the book and a link to Amazon.

Turn Left at Orion: Hundreds of Night Sky Objects to See in a Home Telescope – and How to Find Them [Spiral-Bound]

Guy Consolmagno (Author), Dan M. Davis (Author)

http://tinyurl.com/7sv572a

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Ok, Mars in the binoviewers just blew me away this morning – not to mention Saturn.  I just could not get over the impression of Mars as the eyeball of a gargoyle – an impression that seemed enhanced by the binoviewer’s  faux-3D effect.

But that all came after I did some serious experimenting to try to pin down this business of exit pupil and the apparent astimatism in my eyes. Essentially, exit pupil is the diameter of the cone of light that leaves the eyepiece and enters your eye. I have always been conscious of it in terms of low power in that if it is too large, you’re just wasting the light from your telescope or binoculars. Thus, for example, the typical 7X50 binoculars which are great for daytime use where gathering a lot of light doesn’t matter – are producing a 7mm exit pupil.  For most of us, as we get older our eye just don’t open that wide – 5mm is more the norm.  So that means you may be wasting half the light the binoculars gather – something that is very important for night-time astronomy viewing.

But now I discover from Ed Zarenski – and various astronomy texts I had ignored – that even a moderate exit pupil of 4mm will make it impossible for you to bring bright stars to a sharp focus IF you have astigmatism.  And since I can’t get bright stars to come to a sharp focus in any binocular of any quality that I have ever used, I began to suspect I have astigmatism. And when I did a modest, self-administered test, it does indeed appear that I have it.

50mm Sparow Haek on LXD55 mount.

So I decided to attempt to confirm this from another direction – using a small scope at  various powers to see how small the exit pupil has to be for my astigmatism not to matter. Exit pupil can be calculated by dividing the power of  an eyepiece into the objective diameter of the telescope. In this case I choose a 50mm telescope that happened to be very “fast” – F4 – so it was very much like half a binocular.

I then systematically increased the power by changing eyepieces while the scope was pointed at Mizar, a bright star with a reasonably bright companion separated by 14 arc seconds – something even small binoculars should be able to handle.  But I have never been able to split Mizar with binoculars in the past.

Bottom line – I’m loving using two eyes, but I’m also learning that the only way I’ll see sharp stars with binoculars is to lower the exit pupil, or use glasses that correct for my astigmatism.

I found that with steady skies and Mizar nearly over head I could get a wonderful split – nice and clean – with the 20X60 Pentax I had just bought at Ed’s suggestion.  IF I was very careful about my head position. Not having my head correctly aligned and held steady, the image deteriorates. But this was very encouraging. The exit pupil on these was 3mm – quite small. The image wasn’t perfect, but darned good. Much better than anything I had seen before when using binoculars that gave as much magnification, but also a larger exit pupil – such as the popular 20X80 binoculars.

That’s when I brought out the  50mm F4 refractor, so very much akin to a binocular. I mounted it on the LXD55 (way overkill, but it was handy) and aimed it at Mizar.

I started with a 32mm Plossl. That creates a ridiculously large  7.8mm exit pupil – way wider than my pupil can open, so light is lost – but the fov is wide making it easy to find things. In any event, with a nearly full Moon in the west I could not even see the third star that forms a triangle with Mizar and Alcor. But I at least found the target. No prayer of splitting it, though.

Switching to a 20mm Plossl – 10X – and a 4mm exit pupil and I could not see a split. But from there it  got better as I increased the power. A 17mm gave me 12X,  and a 4.2mm exit pupil and I felt I could see a split, but it was very sloppy with lots of light spikes flaring off the primary and ghostly double images interfering with the view.

A 12mm Ortho gave me my first really good split. This was 16.6X and yielded a 3.1mm exit pupil – very similar to the 20X60 binoculars, so a 3mm exit pupil seems to be the starting point at where my  astigmatism is not as much of a bother.

But the view continued to get better with each increase in power and subsequent diminishing of exit pupil – the 10 was real nice – 20X and a 2.5 exit pupil. With a 7.5mm Plossl I had “refractor like” images – that is the kind I would expect with a long focal ratio refractor – an F12 or F15.  That yielded 26X and 1.8mm exit pupil – so down below 2mm is real good.

And the best images came with a 6mm ortho – 33x and a 1.5mm exit pupil. This gave the kind of performance I expect out of a real nice refractor when skies are steady, as these were.

So where does that  leave me? Well, the binoviewers are no issue at the powers I’m using. For example, on the 8-inch SCT (200mm) I’m using a minimum of 100X and that’s a 2mm exit pupil – so that explains why the binoviewer images are sharp.  Interestingly, though, if I could obtain lower powers I would increase the exit pupil and could run into problems.

Of course, I can get corrective glasses, but wearing glasses while observing is a pain, so if I can avoid that, I would prefer to – and by carefully choosing what I view with I may be able to avoid it. For example, the 18X50 IS Canons would give me an exit pupil of 2.7mm and probably result in a pretty satisfactory image – about like the 20X60 Pentax. But a better choice for me might be the 70mm right angle binoculars that Garrett Optical offers. I could put 13mm eyepieces in those and get a 2mm exit pupil at about 34X. If those are Naglers, then my field of view would be about 2.4 degrees – very respectable. What this boils down to is the 10X30IS are real nice for wide fields. The 20X60 ae great for a lot of binocular double star work. I could get nice, wide field, low power views with the  Garrett 70mm and Nagler eyepieces.  And from there the binoviewers would take over.  In other words, i can see a way to always use two eyes.

20X60 Pentax binoculars mounted on a Parallelogram mount are a good fit for me now.

But, I want to move into this slowly.  So I’ll first continue to experiment and use the Orion binoviewers with  the eyepieces I have. But I am finding it is simply hard to tear myself  away from the binocular view and when I returned to the 20X60 binoculars I discovered how critical head position was, for I could get near perfect images with those as well – if I held my head just right.

This was easiest to do if I actually was a little farther away from the eyepieces than the extended eyecups called for. Going down to the observatory, I put the scope on Mars – keeping in mind that I was in twilight by now, as well as fighting a nearly full Moon. And Mars – small as it is – was spectacular in the binoviewers – I went to two hundred power and feasted on a cosmic eyeball – a ghoulish cosmic eyeball  with orange and greens in it, but the startling white polar cap appearing to distort it and give it the eyeball feeling Saturn was high in the trees to the south, pretending to be one of the Heavenly Twins , paired up with Spica. I had to do a double take when I first saw them, for I knew Gemini was not in that section of sky. The two-eyed view was  simply mesmerizing. For the first time in along time I really wanted to just sit there – not change anything.

bottom line – this was a very enjoyable and productive morning. And yes, I need to explore this business of head position more, and I need to get tot he eye doctor .

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I understand why some folks would think I was  Luddite and in fact a couple referred to me that way in a recent forum on the club’s web site, so I answered there and then realised my answer pretty well spelled out my current thinking on the observing, so I’m including the major part of it here.

See, I would take issue with your term “Luddite” – I know you’re kidding, but other people may think it applies and it doesn’t. “Luddite” implies a person who is opposed to new technology in general and since I sit here surrounded by it in the form of four computers in this room alone and since I still build and maintain several web sites, I don’t see myself quite as a Luddite and most people seem to feel I’m just the opposite – much too ready to embrace new technology.

Let me say once again – because this has to be amply clear – I’m not trying to convert you or anyone else to my way of enjoying astronomy. If you’re happy with what you’re doing, bless you. Enjoy! I’m just trying to explain why I do what I do – which includes offering assistance to folks who come to me and want to learn the night sky. But that’s their decision, not my preaching. And if someone comes to me and asks about what kind of new scope to buy, I will encourage them to stay away from cheap “go to” outfits – as I suspect you would. But if they have the money, I certainly would encourage them to look seriously at something like your LX90. I owned and enjoyed one for several years and think that’s a fine choice for some people – not so fine for others. Just depends.

But that’s the main point. A telescope is a personal decision and should be based on your personal goals and needs. And even when our goals are identical, the decisions can be very different. I am left in awe over the enormity of the implications of what we encounter in this hobby every night. I believe from the conversations we have had, Pete is as well. But Pete and I have very different paths to dealing with that encounter. He chooses to surround himself with complexity in terms of technology – and appears very comfortable in doing so. What’s more, it makes his method of connection possible. I immersed myself in much the same way with video and with a variety of “go to” systems on various scopes that I thought made a better way for me to convey my enthusiasm about the night sky to people who visited and to get them deeply involved with these mysteries.

But it wasn’t working for me. I didn’t feel people were getting the message. I had visitors out practically every clear night and while I got the usual “oooos” and “ahhhs” from folks we all experience, I didn’t think the message was getting through. So I continued to scratch my head and wonder how in the world can I reach people better. Now many, many folks find that imaging is a great way to accomplish what I want to accomplish. Certainly astronomical imagers can become very, very involved with the objects they are imaging. But it wasn’t working for me. In fact, just the opposite was happening. For me – not necessarily for Pete, nor you, nor many, many others – the technology of our hobby was becoming a distraction. So I got rid of it. I still have my Argo-Navis system, but only because it’s part of the 15-inch and if I decide to sell that scope it will be more marketable with that system on it. But I don’t use it.

So the bottom line is, getting rid of all the complex stuff worked for me. I found myself able to enjoy the night sky much more. This applies not only to electronics, but telescopes in general. I want the simplest – and best – techology that works. I wouldn’t call the DoubleStar Mount I have from Universal Astronomics low-tech – but it’s technology appropriate to my goals of simplicity – of having the equipment become transparent – to make my route to “awe” more direct.

And most important for me, is that I am getting the most satisfaction I have gotten in years from my outreach efforts. These were becoming more and more frustrating to me because – as I said – I thought people were connecting, but only in a superficial way. I felt much more was involved when I looked at M13, than when they looked – and I didn’t know how to convey that extra sense of – well, of “awe.” Now you and the other members of this club certainly seem to get that same awe or you probably wouldn’t be doing what you do.

Unfortunately, simply ditching the complexity didn’t work on its own. Even without “go to” I found I had reached a point where I wasn’t reaching people. It relieved me not to have electronics on my scopes – but people were still just standing around at the 15-inch waiting for me to find things for them, then they would pop over to the eyepiece, take a look, and make the required sounds to indicate how impressed they were.

Didn’t satisfy me. I was just the tour leader and I was failing to get folks deeply involved. I’d prepare in advance, I’d tell them about what they were seeing, I’d encourage them to spend more time at the eyepiece, I’d ask questions . . . nothing seemed to really work the way I hoped it would work.

Then came the big break through – the aha moment – which as I look at it now is so obvious I really feel dumb relating it. :oops:

If I wanted folks to get deeply involved all I had to do was turn the scopes over to them and let them find things on their own.

And since doing that – since I switched from being a tour leader to being a coach – my enjoyment has gone up tremendously and I find the people coming to Driftway Observatory have shown a similar increase in enthusiasm and what I think I detect as a depth of awe. (Yes, my personal enjoyment is most important. I’m not a big believer in altruism. I feed on their enthusiasm. If I inspire them and they get excited by what they see, then I get excited. )

That’s why I own three nearly identical 8-inch SCTs and have them installed on simple, non “go to” mounts. With these, and similar scopes, I can set up three or four observing stations quickly and I can turn each over to a visitor and they seem to be having great fun finding and observing just a couple objects each session. (I do limit the number of visitors per session to something I can easily handle.)

This works for me. This works for them. It does not mean it will work for everyone, or it is the only “true “path, or any other such nonsense. But I don’t think it makes me a Luddite either. I’m not going around opposing other people’s approach to the hobby. I suspect people who start with me and my approach may eventually end up immersed in technology. I don’t care. What I do care is that I’m enjoying myself more – that’s of first importance to me – and I’m enjoy sharing the universe with them more. And I enjoy it most of all when I can get 10 people out in the open under gorgeous conditions and have them really get a lot out of an experience where the only technology involved is a single 80mm scope on an alt-az mount and whatever binoculars they had around the house and brought with them – as per my earlier report of observing the new moon and zodiacal light the other night.

But to be a true Luddite I’d have to go around blowing up places like “Wishing Star Observatory” and that’s the last thing I want to do. I love what Pete does for his own satisfaction and the way he is continually sharing it with others and he’s been dedicating himself to these outreach goals a lot longer than I have. That approach is great. Just doesn’t work for me ;-)

Well, that was half the story. As the discussion progressed with others joing in, I found myself spelling out exactly why I think star=hopping works for me.

Rotorhead wrote:. . . And I think that the nugget that is hidden in your words is that we really need to try to get our minds around what it is that we are looking at, so that it isn’t just another ‘thing’ in the eyepiece, regardless of how you found it. For many, many reasons, the low-tech ‘hunt’ is daunting or even a turn-off for a lot of folks. And, as you say, that doesn’t matter – use whatever means you need to find all these astounding objects, but slow down when you get there and try to understand what you are looking at.

You are absolutely on target with that, Bob, and if you had asked me a few years ago I would have vehemently defended my use of “go to” arguing that the hunt,a s you call it, is a total waste of time a childish game of connect the dots played on universal scale. :lol:

Now I argue just the opposite. Again, speaking purely to what works for me , I now think the hunt is critical to wrapping my mind around what I see because:

1. It’s a warm up exercise that helps you shed the other cares of the day and focus more tightly on the universe – in other words to quiet what meditators call “the monkey brain.”

2. It gives you a critical sense of context – this morning, for example, as I approached the Virgo Galaxy Cluster I couldn’t help but notice Saturn, and then Porrima – and that made me think of M53 and I took a little detour to this very distant globular and the whole effect was to increase my “depth perception” – that is, it made me very conscious that I was seeing one object a few light hours away, a second perhaps 30-40 light years away and a third – in the scope – roughly 50,000 light years away. But what I was looking for in the Virgo Cluster were objects in the order of 30-50 million light years away. So the objects provided little stepping stone’s for my mind, reinforcing the concept of the incredible depths with which we deal and reminding me that what looks flat to the eye has a third dimension that is absolutely mind-bending. I just don’t get this impact – in fact I rarely looked at the neighboring sky – when I use “go to.” Instead my focus is downward on a keypad. But that’s me. Another person’s experience may be different.

3. Serendipity – when searching for one thing, I frequently stumble across others – and when trying to remember patterns for star-hopping I again frequently see things that I would have totally ignored had I been using “go to” – including some beautiful asterisms that are rarely, if ever, noted.

4. The part I thought I would miss the most from the electronics, however, is tracking – and I’m still not positive about this in my mind. There’s a real boon to locking into something and staying on it, allowing you to more closely examine it. Maybe. I’m not sure. I have an LX10 and an LX50 now and the equatorial wedges for both and both have clock drives, so it’s easy enough to turn on tracking. But I don’t. I’m tempted sometimes – and if I were in touring mode, showing stuff to a line of visitors, it would be helpful. But with the goal of trying to get our mind around what we are seeing, there are several advantages to having things drift through the eyepiece. It keeps us alert. It gives us different perspective on an object showing it with different surroundings as it drifts from one side of the view to the other – it is a constant reminder that we are on a spaceship that is spinning at about 800 miles an hour at our latitude – and I think you could argue that motion actually increases your awareness of what you are seeing – hey, it works for hawks – and may even make it easier to see faint details, though I have no scientific evidence of this last claim.

But again, the goal is is to really wrap our mind around what we are seeing and in that respect I find the result impossible to measure and nearly impossible to express – but i know I make great strides on rare occasions, while most of the time I find this goal way out of reach. :| I focused on just a few objects when observing this morning with the SV80S Lomo. I stayed on M51 most of the time, intrigued by how much I could see, even at very low power – then gave my eyes a break and switched over to M5, which I haven’t visited in a year – and then, as dawn was rising, I made a quick check on M12 and M10 – I could just fit them both in the same fov when using the 30mm (82-degree) Clearvue, my “finder” eyepiece. ;-)

It was an interesting journey, but I’ll be damned if I could get where I wanted to go, or bring anything back from it I’m able to communicate. Maybe tonight will be different.

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Rose and Joe came out last night for a couple hours of star-hpping. They both used their ownbinoculars,  the 50mm Tasco, and the  80ED/C8 on dual mount.

First target was the Beehive, which shows well in the 50mm at low power. ( I switched froma  40mm Plossly to a 32mm Plossl which seems to give about the same field, at slight higher (19) power.) The next step up is the 18mm Meade wide angle which gives about 33X and works beautifully on M42, just barely reveal the Trapezium.  Barlowed,  it does even better.

Joe found the Beehive witht he dual scopes, then Rose did and Rose also found M35. I showed them NGC2158 right next to it – but much,much fainter since it’s about five times farther away.

High clouds came in just as we were wrapping up, but before they did Joe was able to locate M37, M36, and M38 with his binoculars.He had been having a frustrating time with them earlier, but I think that was because they were straight over head – an uncomfortable and idfficult situation,

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Sweeping up old, familiar galaxies was not nearly as easy as I thought it would be – but then, I somehow managed to miss the Shuttle Endeavor streaking across the sky at -0.5 magnitude – in total a rather humbling experience that  proved the fun of being wrong. Maybe you can set me straight if you care to wade on through to the end 😉

It all  started about 10 hours before with a little modest testing.

I need to find a cure for my telescope addiction – I can’t even tell you how many scopes I’ve bought and sold in the past six months and since I’ve been scratched unceremoniously from Astromart – those folks have no manners – the trail I left has vanished  🙂 But buying and selling used scopes does have it’s upside, though, in that I get to experience a lot more options than I ever did before. In any event this latest round was making me think we cut this whole telescope size business way too fine.  OK – I’ll be careful about the use of the word “we.”  Imagers are understandably more demanding of a scope than I am, and for that matter so are a slew of visual observers who are much more tuned in to detail than me. So I’ll just say that for me, the differences between an 80mm scope and a 120mm just aren’t that obvious. Heck, I hardly use my 15-inch at all these nights because the smaller scopes seem to meet my demands with less hassle. But this doesn’t stop me from getting on a kick where I decide that I really “need” a six-inch achromatic refractor. Because of their size  – and recent favorable reviews on Cloudy Nights – I was looking at the Explore Scientific, an  F6.5 152mm scope – and a similar one, but different brand, from Hands-on Optics.

But just how much light do I gain with the 150mm?  I can do the math, but what it boils down to is what is  the faintest star I can see. Yes, I know all sorts of games can be played with these numbers as well. But for comparison purposes  I decided to accept the Orion numbers  as at least relatively correct.  They show the [b]80ED with a limiting magnitude of 12.2, the 120 ShortTube at 13.1, and 150mm Celestron they sell at 13.6.[/b] By those numbers the F5 120mm achromatic offers almost a full magnitude jump over the 80 ED and the 150mm adds another half a magnitude.  So what’s that mean in real observing experience? Answering that question was my goal last night. I don’t have a 150mm scope right now, but I do have an 80ED and a 120ST and so I could put them both on the DoubleStar mount, use the same diagonal and eyepieces for both, and see what I could see.

The focal length for both scopes is 600mm, so that ruled out magnification as an issue. Yes, there was a first quarter moon dominating the area near the zenith, but so what? The playing field was level, if a bit washed out.  I pointed them at M42 as a starting point. The 120mm view was obviously brighter – or was it? That was my first subjective impression and I think it was accurate – but when I tried to prove it to myself by tracing the extent of the nebulosity – especially with M43 – I just couldn’t pin down a real difference. And when I scanned for the faintest stars visible there was nothing in the 120mm that I couldn’t find in the 80mm – though I must admit the stars on the borderline were a tad easier to see with the 120mm. But nothing blew me away. Nothing said  “wow, i really need more aperture than the 80 can offer.” (OK  part of this might be better glass and a slower focal ratio in the 80 – but light grasp is light grasp, right? Size is the major factor.)

I won’t recount all the details of my little experiment. Suffice it to say I repeated my test on two open clusters,  M35 and it’s much fainter companion, NGC 2158. Then I switched to M1. I played around changing diagonals – I had one for each scope, but I switched them back and forth to make sure that wasn’t causing the difference. I also upped the power, starting with a 24mm Panoptic, but also using 13mm, 7mm, and 3.5mm Naglers. [b]Where did the 120 shine? On NGC 2158 and  M1. [/b]These low- surface brightness objects were difficult targets in the moonlight and while I could barely detect NGC 2158 with the 80mm under these conditions, I could actually observe it with the 120mm. M1 showed in both scopes, but was certainly brighter and easier to see in the 120mm. So with marginal targets you start to really notice the added light gathering power. But with many targets the difference just wasn’t enough to make me crave a larger scope.

This is good.  I really don’t want to sell the SV80S Lomo – though it would more than cover the cost of a 150mm achromatic – and when I started observing that was my plan. But just to get my feet solidly back on the ground I did one more test. I looked at  Algieba, a favorite double, that was fairly low in the east, it’s altitude aggravating the already poor seeing. The 80ED showed me a wonderful pair. Little, bright dots with subtle color. Charming! The 120mm gave me the kind of sparkling stars that fascinate Cub Scouts who visit Driftway Observatory, but are not what I’m seeking. Sparkling lights are nice on Christmas trees – not so nice when trying to split doubles.  I took the 120mm off the DoubleStar and replaced it with the C8 SCT. Algieba calmed down a little, compared to the 120mm (remember it is an inexpensive F5  and not intended for double stars). But the 80 ED gave the best images.

This isn’t really a fair test. I don’t expect the F5 achro to perform like and F7.5 apo-wannabe on doubles. But I’m have trouble believing that any six-inch refractor that is short enough to work well on my mount  is just not going to be able to deliver the kind of star images I crave. Mind you, the split was wider in the other larger scope. Increased size does mean smaller star images.  I’m not saying an 80 ED can do everything well. But this was an enjoyable 90 minutes of observing and it cured me of my current lust for a 150mm achro. I’m not knocking these scopes. Just saying they don’t offer enough extra light grasp to make me want to part with a smaller apo to get one.

So I went into the house at peace with my scope envy for the time  being, watched a little Olympic speed skating, and actually got a very rare six hours sleep – delightful. Felt I could conquer the world – and since it was now 4 am there was still time to get out to witness the 4:34 am pass of the Endeavor  – I had checked Spaceweather.com’s “Satellite Flybys” before going to bed – which was to be followed a few minutes later by the ISS. By 4:30 am I was comfortably settled on the Observing Deck with my hot seat (“Lava buns”) beneath me, my tea beside me, and my super-wide-angle 5X24 Bushnells in hand. These are my “Lyra” glasses in that they can show that entire constellation with plenty of breathing room around it. Even with just 10 minutes dark adaption I was seeing every star in the Little Dipper. Transparency was a five – in magnitudes, I’d say 5.5.  Wonderful. No wind, either.  But the Endeavor was due to appear in the ENE and not be all that high. I figured that would put it in the apple tree branches pretty quickly, so I took a short walk to my easterly viewing station where it’s clear to the horizon – and I waited, and waited and … checked my clock and it was now several minutes past the appointed time.
[b]
How the heck did I miss something of magnitude -0.5 moving across the sky?[/b]

“Pop” – there was the ISS, right on schedule, though not as bright as the morning before. But no Endeavor.  I must be going blind.

But I didn’t give it much more thought because I wanted to take advantage of this great transparency and I didn’t have much time left before astronomical twilight began. So I went back to the deck and swung the 80/8 – that’s my new shorthand for the 80 ED and C8 combination on the DoubleStar – I swung it in towards the hole between Denebola and Porrima where I knew the Virgo galaxies hang out. Haven’t made any serious excursions in this direction this year, so my memory of exactly what is where isn’t that fresh. But I figured with a 2.7 degree fov on the 80 ED with 24mm Panoptic I should be able to sweep up M84/86 or at least some of the members of Markareian’s Chain. Wrong!

I don’t know how I missed them. This was at least as mysterious to me as the missing shuttle. I swept a couple times with the 80 ED, then switched to the 8-inch, also with a 24mm Panoptic and  focal reducer – no luck.

Well, not zero luck. With both scopes I kept stumbling across two galaxies. But they were singles and in this territory I’m used to seeing at least two galaxies at a time, if not four or five. The first was bright and round and while I didn’t recognize the star patterns in the field – quite bright and distinctive, I might add – I assumed this was M87. The second was dimmer and fairly near an 8th magnitude star and my memory told me that was M58. But if so, where were the other galaxies? I couldn’t place M87 in my mind  in relation to the other galaxies – for some reason it has never interested me much – but I new it was in the neighborhood. But no cluster galaxies. Finally I gave up.  I did stare at “M87” for quite a while and noticed a few individual stars which I assumed must be foreground stars in our galaxy.  And what a wonderful cascade of bright stars leading down to it!

Can you guess now where I was? Do I hear Bob Magnuson saying “dummy, you were on M53!” If so, Bob, you’re right. I went in and checked the charts, having committed the field stars to memory. Yep. That was an M53. Why the heck did they put a globular cluster so close to this galaxy field”? I don’t know if I’ve every looked at it. Or maybe I looked at it in my “go to” days and so didn’t appreciate its spatial context? (that’s one reason I’m no longer a fan of “go to” – I just wasn’t getting to know the  neighborhood!)  In any event, it’s worth another look, and this is what I like about being wrong.

Yes, I do plan many observing sessions and research extensively before going out. But other times I like to explore, find something, note its surrounding, then when the sky lightens, or the cold drives me in, I have fun figuring out what I had seen. In this case, what I read when I came in makes me eager to get back to M53.

[quote]William Herschell described M53 as one of the most beautiful sights in the heavens. Still, this whopping, 200-light-year-wide sphere of stars is an unsung hero among globulars for small telescopes. Perhaps that’s because it sits on the fringe of the Como-Virgo-Cluster of galaxies like a flower outside a forest of redwoods.
[/quote]

That just a taste of what Stephen James O’Meara has to say in “The Messier Objects.” Flower indeed – and I could find the flower, but not the redwoods! 😳

Ronald Stoyan, et al in “Atlas of the Messier Objects” points out that M53 was discovered in the early morning hours of the 3rd of February, 1775 by Johann Elert Bode who described it as “lively and round.” Yep – I can relate to that Johann. Imagine what it must have been like to be the first to see something like this! And this sucker is big! I mean, M13 blows my mind, but M13 is more than twice as close to us.  M53 is 63,000 light years away, has a diameter (accoridng to the Atlas)  of 230 light years, and about 750,0000 solar masses.  I’ll be back for a better look.

And what about that other dude? the one I thought was M58. Dimmer, mind you, than M53 – and keep in mind, I was using low power the whole time.  But it was a galaxy. Figured it out? It was bracketed by a triangle of  stars – a fifth magnitude star on one end, and the other two magnitude 7.  That help?

If you answered M64, the “Black Eye” galaxy, you are right and your star-hppomg slills far exceed mine.  Now that one I should have known – or probably would have known – if I had increased the power. But at this point I was keep the power low, the field wide, and trying to remember identifying field stars – so I didn’t notice the dark splotch on the core. And it was getting light. By the time I backed off these two the faintest stars I was seeing with the naked eye were magnitude three. But I like being wrong this way. I learn more.

OH – and the missing Endeavor? You all have that figured out, don’t you? When my wife got up I recounted my experience with it to her.

“I thought they landed last night,” she said innocently.

🙄

Oh my. Maybe I should look at the news once in a while. I didn’t even know there was a possibility of them landing last night. I just took the Spaceweather predictions as gospel. Maybe there was some fine print I had missed. but sure enough, they had come down last night, though early in the evening they thought the weather was going to keep them up.

But this is good news, too. I’m not blind. Nor did they crash.

And hey – it might still be clear enough to observe tonight, though the forecast for the rest of the week sure is dismal!

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Boy, this observing period didn’t start out as advertised! Wonder of the folks doing the public outreach at UMass Dartmouth encountered what I did a few miles away?

I had a session scheduled for 7 pm with one of the  “star hoppers” group and the forecast looked wonderful. In fact, when he arrived he couldn’t take his eyes off the sky and I had to keep reminding him to watch out for the slippery ground as we walked to the Observing Deck. Once there, I introduced the topic  for the night – open clusters – and explained how the observing log form encouraged him to look for specific aspects of a cluster, such as density, color of stars, patterns, etc. That maybe took 10 minutes and in that time the sky nearly entirely clouded over and the wind went from 7-10 mph to gusts of 30-40 mph! Incredible. We hunkered down near the fence that surrounds the deck, well-sheltered form the worst of the cold wind, and hoped this wasn’t throwing a monkey wrench into the club’s outreach efforts at UMassD. It took perhaps about 15-30 minutes for the skies to clear entirely. As little pieces opened up we got a look at Vesta, still in the same binocular field as Gamma Leo and its companion, but well beyond those two stars. More sky opened and we could pick out Auriga and I explained where to start looking with binoculars for  M36 and it’s two neighbors, M37 and M38.

These were high overhead and that’s where I began to miss my Hotech laser – badly. It’s an Astro Aimer G3 – pricey, but it includes white light, red light, and green laser in one unit – nice. For the first few months it worked fine.  But then about a month ago the laser started acting up. I thought it was just the cold and didn’t worry too much about it. But then the white light started getting erratic and after that the red light. The clincher came when I switched to fresh batteries and suddenly nothing worked! So it’s on its way to the folks at Hotech who have promised to replace it free of charge – nice, since it was 11 months into its one year guarantee! But I had forgotten how difficult it could be to help someone find something like these clusters – now high overhead and roughly 40 degrees from a 7-day-old moon that was washing stuff out somewhat.  As I noted, I get cranky at night – sleep deprivation – and I wasn’t the most patient of instructors. Fortunately, my visitor was much nicer than I deserve.

Bottom line, he eventually found all three clusters in his 10X50 glasses, despite the moonlight. We then switched to the Universal Astronomic DoubleStar mount. This is cool. Right now it has a C8 SCT with a Telrad sight on it and mounted next to that is an 8omm Orion  (80ED) with the 30mm Clearvue eyepiece that delivers a 4-degree true field of view at 20X. That’s almost as much as the binoculars, but with more light grasp and power.  So the process is get in the territory – now familiar from his exploring it with binoculars – by using the Telrad. He found M36 ( the easiest to start with IMHO) and then moveed to M38. The two fit in the same 4-degree field. M37 is a bit of a stetch in the other direction, but not hard. And, of course, when you have found the target and appreciated  the context that the wide field of view supplies, you then move to  the 8-inch. I use a focal reducer on this to bring the focal length down to 1260mm, so with the same eyepiece as use dinthe 80mm, the C8 is producing about double the power – and half the field of view. And that was the program for the night – compare and contrast these four. I think he did very well, becoming very familiar with that wonderful region of sky, and certainlys eemed to enjoy the accomplishment.

I didn’t fare as well. I fooled some more with the  Celestron FirstScope which continues to disappoint. I’m pretty sure I have it tuned up as good as it gets now and while it will reveal the Trapezium, for example, using its 4mm eyepiece, I only see it because I have seen it so many times I know what to expect. I feel a new user would probably notice just one star there. (Granted, seeing, was poor, but other scopes in the same size category could handle it better. I also played with a 6-inch Orion  “classic” DOB. I like this scope, but I’m not all that happy  with pointing a DOB. I’m spoiled by  nice, small refractors and the workhorse, 8-inch SCTs.

Morning, as usual, was better for me, though my four hours of sleep was fitfull. I don’t think I would have gone out, except I knew a good pass of Endeavor, followed by the SST, was in the works.  I really got to enjoy the DoubleStar and refined the pointing on it so that the target is centered in both scopes, even at moderate-to-high powers. I plan to review this, since it’s new – not only to me, but to the market – but I want to live with it a while. I always tend to be overly enthusiastic with a new piece of equipment at first. Now that I have these two scopes in sync on it, I’m wondering what will happen when I remove them, then do another set up next time its clear. I expect they will be close – but not sure if they’ll have to be finetuned again.

I used it on several familiar targets, but my real goal was to see how it would do on the ISS – and the answer is great!  I had a 24mm Panoptic in both scopes. That gave me 25X and close to  3 degrees in the 80mm. In the  C8 with focal reducer it gave me 52X and a bit more than a degree. So when Endeavor appeared right on schedule in the NW and climbed about 30 degrees I lead it with the Telrad sight, switched to the  80mm and it soon came into that scope’s field. I got it on the centerline and switched to the  C8 – Wow! Not like its photographs. Too much dazzle and seeing that was still a “2” at best.  But I could see one elongated bar with three bright bars crossing it,  I’m not the super patriot sort, but seeing the ISS and  a shuttle play tag almost always brings tears to my eyes – makes me feel our species, despite its many blunders, may indeed have a future.

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