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unlearning the constellations

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#1 drollere

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Posted 18 October 2012 - 07:15 PM

last night, bad seeing prompted me to tour the milky way with a binocular, something worth doing anyway at this time of the year.

i am reasonably familiar with the milky way large scale structure, and as i was indulging in my imaginative recognition of how far away the different star fields were, i realized that the constellations actually get in the way.

we all learn the constellations in our novice steps, and these ingrain certain asterisms in mind as if they are equally distant stars appearing at pretty much their absolute magnitudes. this is so far from the truth that it seems necessary to unlearn the constellations in order to make sense of the sky.

i've posted some animated gif images HERE that contrast apparent brightness, spatial distance and absolute magnitude of stars in the summer and winter milky way. the differences between the representations are pretty drastic.

thematically the distance image suggests the random scatter of stars; the absolute magnitude shows the clustering of OB and A types within the milky way plane. what's remarkable is that the visual patterns of the constellation asterisms have nothing to do with either. the puny brightness of vega, altair and arcturus, and the far brilliance of deneb and antares (or the whole of orion) are striking.

my sentiment is that astronomers generally spend too much attention on getting large aperture to see faint details in far galaxies, when there is a wealth of dense detail -- nebulae, galactic clusters, giant dust and molecular clouds, star clouds, layered features lying in different spiral arms -- that is available for study in our own galaxy, even with the naked eye. why is this so commonly ignored?

i think a large part of that has to do with the pinhole mentality of the catalog list and GOTO mount: we go about looking at specific objects that are only arcminutes wide, at best. the idea that a spacewalk eyepiece is *so* much better than a drinking straw eyepiece obscures the basic fact that they both show you a minuscule fragment of the celestial sphere. put that 17mm 100º $800 tele vue ethos in your 16" ƒ/4 dob and you get to see 0.0024% of the sky at any one time!

we piece together glimses of these pinhole samples of the sky as isolated features with nonsense pidgin arabic or cartoon character names, and call it "astronomy" with the absurdity of someone who has a pet name for every piece in a 100 or 1000 piece jigsaw puzzle but has never put the puzzle together to see what it represents. deep sky, double star, list chasing astronomers, we all fall into this trap. constellations only cement the delusion -- all those stars "go together" in a completely arbitrary patch of sky, even though the stars usually have nothing to do with each other and in our minds have only a hazy connection (if any) to the landscape they inhabit.

here's my puzzle: what to do? what is the most effective way to unlearn the constellations and reconnect the visible stars so that we can recognize similar distances or galactic regions? how might we learn the very simple distinction between population I and II stars in the general direction of the galactic pole? how can we learn to recognize at least a few major OB associations? what are the major landmarks -- orion, the hyades, the brightest near stars -- that give us some traction?

the problem seems so big that it's hard to know where or how to begin. it seems to me that binoculars, night vision scopes or the naked eye are the essential tools to work with ... but what books, software or atlases can assist? there is a very weak connection between concept renderings such as GALAXY MAP and the appearance of the galaxy with binocular or eyes.

my animated gifs may impress that visual brightness provides a very weak foothold onto the imaginative problem of seeing the big landscape of our home galaxy. perhaps we look at far away objects in isolated and tiny fields of view because ... it is just so much easier to do.

#2 GlennLeDrew

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Posted 18 October 2012 - 10:42 PM

Bruce,
You're doing pretty much exactly what I started out on about 20 years ago. And I'm still at it!

After hunting down many hundreds of DSOs, this began to get tiring. The next logical step was to strive for a more holistic understanding of the location, nature and kinematics of these objects, and how they are related within the scheme of the Galaxy.

By taking such an approach, one finds a *lot* to learn and see in our corner of the Galaxy. And no big light buckets are required; a binocular is quite adequate for much of this study.

Multitudes of dark clouds, scores of young stellar associations and star forming regions and the Gould Belt are some brand new territory for the observer looking to feel the excitement of fresh discoveries. And building up a mental 3-D map of all this stuff will transform the 'flat' dome of the sky into a dynamic ocean of space.

#3 magic612

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Posted 18 October 2012 - 10:42 PM

Bruce, that's an interesting question - or should I say, interesting questionS. I'm not sure I have any easy answers.

As to myself, I've found that I have been learning new things about the sky as I research for my weekly astronomy videos. I can't say I've made too many connections (yet) with respect to the specific objects you mentioned, except perhaps when I did a "zoom" towards Orion's belt stars in this video from April. I found it an interesting view to see how ALL of Orion's stars seem so bright, and yet are so different in distance. I'm not sure if that correlates to what you're getting at with regards to stellar associations though.

But the one area I have forced myself to "unlearn" and think about the sky in a larger, more macro-sense is with globular clusters. I started looking at WHERE they all are, in relation to the galactic center and galactic plane. It really is interesting when one starts to look at where these objects reside in relation to both the Milky Way in general - either side of it - and the concentration of them as well as the dispersion of them the further one goes from the galactic center.

I'm not sure if that's exactly what you're getting at, but I found it a fascinating way to look at the sky in a larger sense, despite the fact that the objects themselves are still small (from our perspective). So I guess that's my only "unlearning."

#4 drollere

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Posted 19 October 2012 - 12:56 AM

starting with the globulars is probably a very good strategy. that's how shapley deduced the location of the galaxy center, and the sun's distance from it.

i remember my surprise when i learned that the pleiades are actually much farther from us than the hyades -- they seem bright enough to be closer. maybe there is a selection of 50 or 100 stars that can be used as signposts to the distance and direction of specific features, in the way deneb is close to the root of the orion spiral arm.

glenn, i have enjoyed your interest in intergalactic clouds and milky way structure in some of your past posts. can you perhaps review your steps to a more holistic understanding, the big pieces that helped solidify the details?

i remember the first time i learned about barnard's loop, and the fact that the horsehead nebula and the great orion nebula, always photographed and described as separate objects, are actually parts of a single enormous feature. there must be dozens and dozens of similar connections to be made.

#5 Jon Isaacs

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Posted 19 October 2012 - 05:06 AM

my sentiment is that astronomers generally spend too much attention on getting large aperture to see faint details in far galaxies, when there is a wealth of dense detail -- nebulae, galactic clusters, giant dust and molecular clouds, star clouds, layered features lying in different spiral arms -- that is available for study in our own galaxy, even with the naked eye. why is this so commonly ignored?

i think a large part of that has to do with the pinhole mentality of the catalog list and GOTO mount: we go about looking at specific objects that are only arcminutes wide, at best. the idea that a spacewalk eyepiece is *so* much better than a drinking straw eyepiece obscures the basic fact that they both show you a minuscule fragment of the celestial sphere. put that 17mm 100º $800 tele vue ethos in your 16" ƒ/4 dob and you get to see 0.0024% of the sky at any one time!



Bruce:

Some interesting stuff, translating the 2 dimensional views of the eyepiece to the 3 dimensional (ignoring time) views that science and careful measurement provides us. That is an integration of the senses with the intellect.

We all enjoy the sky in a different way... I very much enjoy just wandering around and seeing what I can see, figuring out what it is, learning something about it... I don't use GOTO, I view the constellations as part of the road map, sign posts to help me find my way from one part of the sky to another.

I am a big believer in using a telescope as an instrument of discovery rather than as tool to go down a list of objects... It's a different paradigm. I mostly work from the sky to the books rather than from the books to the sky. But I have to admit that I think in 2 dimensions...

At some point, one has to recognize what it is that draws one to this hobby... For me, it's not the science as much as it is the aesthetics, I just enjoy looking through a telescope/binoculars/naked eye at the night sky... It's just neat being out there under the night sky.

Binoculars are good but for me, a scope like the NP-101 with a nice eyepiece like the 31mm Nagler is better and even better is a collection of telescopes that provide different views on different scales... There is a lot of neat stuff to see... it's neat to look through big scopes, it's neat to look through small scopes and there is a lot to be learned doing both.

Jon

#6 magic612

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Posted 19 October 2012 - 07:23 AM

At some point, one has to recognize what it is that draws one to this hobby... For me, it's not the science as much as it is the aesthetics, I just enjoy looking through a telescope/binoculars/naked eye at the night sky... It's just neat being out there under the night sky.


Interesting that you say this, Jon. That also describes me to a tee. In some ways, I feel a bit "outside the norm" in that regard, but reading you say that, it also makes me wonder how many others feel the same way.

But I don't want to drag the thread off-topic either.

#7 Doc Willie

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Posted 19 October 2012 - 08:09 AM

. . .even better is a collection of telescopes that provide different views on different scales... There is a lot of neat stuff to see... it's neat to look through big scopes, it's neat to look through small scopes and there is a lot to be learned doing both.

Jon


My dream observatory would have room to have at least three scopes set up all the time -- a light bucket, and 8" SCT Go-to, and a refractor.

#8 Dennis_S253

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Posted 19 October 2012 - 09:14 AM

I have been trying to stay away from this thread, but something keeps pulling me to it. I personally take it a little offensive with your so called "pinhole mentality". If it pleases someone to set up a scope and view the wonders of the sky then so be it.

#9 csa/montana

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Posted 19 October 2012 - 09:27 AM

We all enjoy the sky in a different way... I very much enjoy just wandering around and seeing what I can see, figuring out what it is, learning something about it... I don't use GOTO, I view the constellations as part of the road map, sign posts to help me find my way from one part of the sky to another.

I am a big believer in using a telescope as an instrument of discovery rather than as tool to go down a list of objects... It's a different paradigm. I mostly work from the sky to the books rather than from the books to the sky. But I have to admit that I think in 2 dimensions...

At some point, one has to recognize what it is that draws one to this hobby... For me, it's not the science as much as it is the aesthetics, I just enjoy looking through a telescope/binoculars/naked eye at the night sky... It's just neat being out there under the night sky.



Jon, we are kindred spirits in our viewing! I view exactly in the way you describe.

The main point is, yes; we all view the beautiful night skies in different ways. One person's way does not make another's wrong. The "pinhole mentality" is rather discouraging to us, that prefer to view the night sky thru our scopes.

My telescope has opened up a whole new, exciting world to me; I would not enjoy it nearly as much without my telescope; pinhole mentality? Maybe, but it sure is fulfilling to me. I love to put my 30ES in, and just wander all over the sky, stopping at something that looks interesting.

I take many breaks from the scope, & open up my camping chair, and lean back & just drink in the night sky; to me, the scope & just sitting in a chair looking up; is the best of both worlds. Again, there is no "right or wrong" way to view the night sky, as long as you enjoy it!

#10 Jon Isaacs

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Posted 19 October 2012 - 10:42 AM

My telescope has opened up a whole new, exciting world to me; I would not enjoy it nearly as much without my telescope; pinhole mentality? Maybe, but it sure is fulfilling to me. I love to put my 30ES in, and just wander all over the sky, stopping at something that looks interesting.



Carol:

That hardly sounds like the pinhole mentality to me. Rather that is very much in line with the concept of a telescope being an instrument of discovery.

The "pinhole mentality" a 5 inch scope with a 1.25 focuser and a 1900mm focal length that requires GOTO to make it useable. It's driving nonstop the 143 miles from the Grand Canyon to the Betatakin Ruins at Navajo National Monument without taking the time to appreciate all the wonders in between.

What I suspect is that Bruce maybe moving away from an individual object oriented list based observing mentality to a universal the "whole sky is one big DSO" paradigm and adding an intellectual 3D aspect.

Myself, I just like looking. Beginners Mind, Zen Mind... "I ride my bicycle to ride my bicycle." I look through my telescope to look through my telescope.

Jon Isaacs

#11 csrlice12

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Posted 19 October 2012 - 10:50 AM

"At some point, one has to recognize what it is that draws one to this hobby... For me, it's not the science as much as it is the aesthetics, I just enjoy looking through a telescope/binoculars/naked eye at the night sky... It's just neat being out there under the night sky."

Couldn't have said it any better.....

#12 Astrodj

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Posted 19 October 2012 - 11:17 AM

Bruce,

I imagine a planetarium program that could be told to show the naked eye sky from any location in or near the galaxy. It would be like having a virtual spaceship. One would quickly get lost if the program were so sophisticated as to able to put the reference point into light years per second motion.

I wouldn't mind heading out toward the Cone Nebula and tooling around for a while to see what the area looks like from other angles. :grin:

My interest in forming a mental picture of the actual 3D location of common celestial objects within our galaxy took
flight when I learned that the vast majority of what is visible to the naked eye is contained within a relatively small bubble of space with a radius of roughly 1500 parsecs, with us being in the center of the bubble.

Only 7,000 or so of the nearest AND brightest stars are visble to the unaided eye, mostly within that bubble, out of 2 or 3 hundred billion stars in the galaxy. Over half of either total are red dwarfs with only a scant few visible without optical aid, even the relatively near ones.

Looking toward the learned constellation of Saggitarius without optical aid, we can see (with a few exceptions) only about an eighth of the distance to the center of our galaxy. Same story along the galactic plane in the opposite direction towards the outer edge. Then there is the other entire half of the galaxy left to consider.

It's a lot to map, and I have only a very rudimentary knowledge of where the objects I can see actually are on that map so far, but I'm learning.

I too spend most of my time observing the "objects" in a telescope, because I enjoy it so much. But, I do make an effort to mentally place said object within our galaxy where it belongs, as best I can. Knowing what else is also in the locale of that object however, is another question that goes largely unanswered for me most of the time.

#13 csrlice12

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Posted 19 October 2012 - 11:25 AM

To someone somewhere else, our sun is just another star, maybe part of the handle to the whatchamacallit costellation.

#14 csrlice12

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Posted 19 October 2012 - 11:25 AM

Duplicate Post deleted by csa/montana

#15 bassplayer142

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Posted 19 October 2012 - 11:32 AM

I've found that getting a sense of depth works a lot better in dark skies. Unfortunately I don't have those. As far as distances of star fields, it seems safe to say that the dimmer it is the farther it is in general.

Next time I look at a good globular I'm going to try to visualize it three dimension-ally by thinking about star brightness and see what happens.

#16 Astrodj

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Posted 19 October 2012 - 12:01 PM

One of the reasons I enjoy Burnham's Celestial Handbooks so much is I get a rough idea of the distances to many of the brighter stars, clusters, and nebulae. Combine that knowledge with the general direction of the object in the night sky and I can come up with an approximate placement within the galactic plane, reference our sun and it's location in the galaxy.

#17 Astrodj

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Posted 19 October 2012 - 01:13 PM

we all learn the constellations in our novice steps, and these ingrain certain asterisms in mind as if they are equally distant stars appearing at pretty much their absolute magnitudes.


I think people who have been at this a while are aware that distance variations exist between stars of the constellation asterisms, star brightness is apparent not absolute, and that the groupings are line of sight. It is probably the rare individual that can look at a given constellation and recall from memory the different distances of even the brightest members, forming a mental 3D image. Sounds like maybe a good place to start actually.
:question:

constellations only cement the delusion -- all those stars "go together" in a completely arbitrary patch of sky, even though the stars usually have nothing to do with each other and in our minds have only a hazy connection (if any) to the landscape they inhabit.


Well, they do have something in common. They lie in generally the same direction of the galaxy from us, which narrows down considerably their location in two dimensions. I agree with you that the landscape they each inhabit is something I remain largely unaware of without considerable legwork in the books. Even then it's pretty sketchy.

perhaps we look at far away objects in isolated and tiny fields of view because ... it is just so much easier to do.


Personally, I do it because I enjoy the view, narrow as it may be. :grin: I also find the 3D reality of the bigger picture fascinating, and see no reason you can't be interested in primarily one or the other, or both. :jump:

#18 csrlice12

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Posted 19 October 2012 - 01:23 PM

and I know in my mind the sun doesn't set, it's the earth's rotation that is accounting for this phenomena; but that doesn't mean I don't appreaciate those beautiful sunsets....

#19 drollere

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Posted 19 October 2012 - 02:58 PM

I have been trying to stay away from this thread, but something keeps pulling me to it. I personally take it a little offensive with your so called "pinhole mentality". If it pleases someone to set up a scope and view the wonders of the sky then so be it.


there are two ways to misinterpret a post, and you've done both.

first, imagine your view of the universe is that you are wearing opaque goggles, with a pinhole in them centered over your pupil. you can see out, but you can't see much. or imagine that you can only use your telescope with a single high powered eyepiece -- but your head is covered with a cloak and you can't look at the sky. how will you be able to perceive what is actually around you, or what the sky looks like "big picture"?

now pick up astronomy books. messier lists, herschel lists, double star lists, showcase objects, the burnham cabinet of curiosities ... where is there a book that tells you about the big picture, puts all these objects in context? besides crossan's "binocular astronomy", i can't think of one.

my point is: your view is limited by the *way* you are looking.

second, why is suggesting that people pay more attention to something mean they should *stop* paying attention to something else? or that paying attention to anything else is *wrong*?

my appeal was for some ideas to help make the big picture easier to see, to remember, to teach. for references to books that talk about the big picture. for concepts or signposts that make it easier to visualize. all that, because our galaxy is the biggest, brightest, most detailed, most resplendent galaxy it is possible for us to see ... no matter how big your aperture or observatory.

but you took all that as vaguely insulting, and i regret i helped you get there.

#20 Dennis_S253

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Posted 19 October 2012 - 03:58 PM

I knew I should stay away from this. Starting with the title, "unlearning the constellations". They have been around for thousands of years. They are guides. We say things like, look for M42 in Orion by the sword. That's an area where new stars are forming. I'm not sure what big picture you want I guess. Yes the galaxy is huge. The universe is a lot bigger. Yes, I guess you could say we are looking through pinholes. I can't see it without the pinhole though. There are a lot of good TV shows that talk about the big picture. History channel, discovery and a few more. There are some good books, The universe as we know it. I'm sure there's a lot more.

#21 drollere

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Posted 19 October 2012 - 04:07 PM

We all enjoy the sky in a different way... I very much enjoy just wandering around and seeing what I can see, figuring out what it is, learning something about it... I don't use GOTO, I view the constellations as part of the road map, sign posts to help me find my way from one part of the sky to another.

I am a big believer in using a telescope as an instrument of discovery rather than as tool to go down a list of objects... For me, it's not the science as much as it is the aesthetics, I just enjoy looking through a telescope/binoculars/naked eye at the night sky... It's just neat being out there under the night sky.

there is a whole physical, sensual, spiritual, emotional and esthetic dimension to astronomy, certainly. it is neat, but i wasn't addressing it specifically.

there are many ways to see, study, appreciate, enjoy the night sky with the use of optical instruments. whatever anyone wants to do, however they want to do it, is fine with me. (as if what i thought had the slightest importance to how or why they want to do what they do.)

i *am* saying that there are walls around the common approach. once you look for them, they are palpable. the novice asks, "what is the best magnification?" -- the advice is: why, the magnification that frames the object. start with the object, which can't be more than a few arcminutes wide, and put a frame around it. cut out everything else, ignore it, assume it doesn't matter. then go on to the next object, put a frame around that, and so on.

what's a good book about astronomy? well there's this book here, that gives you a *list* of things to look at, or a chapter on each of 100 objects, all separately described. ... and how many other books are just like that one? isn't there fundamentally a routine and limitation in the *information resources* available to us? aren't we habituated to look at the sky in a certain way by how we find things to look at?

the point made above about light pollution is right on. glare does nudge us to look for bright, discrete, identifiable targets, because the milky way is blotted from view. but so too do books and atlases that never indicate there is anything else to see, that show the milky way as a smear of monotone. it's remarkable that one of the most intimate and detailed descriptions of the whole milky way available anywhere is in ... ptolemy's almagest, Book VIII.

i greatly admire jon's approach to observing, and i endorse it as incredibly pleasurable. i once started from beta cygni and worked my way by random slews up through gamma and out to delta, and still remember it as something like a boat cruise up an enchanted river. i discovered many things that i could not later identify with a catalog. i was the tourist who just puts the tour guide in the backpack and wanders up an alley.

but also like the tourist who wanders without a map. it's not just that we habitually look in a certain way, and there is another way to look: it's that we don't have the resources to make any other way of looking informative. fun and stimulating, yes, but enriching, insightful, illuminating, educational? if we had signposts as we wandered, the whole experience would be more memorable. we could actually see and comprehend our place in the galaxy.

i liked the suggestion made about a software program focused on these topics. where can i get it? the software > Where is M13? < is a rudimentary version of what i had in mind, but it does not link the objects to the visible milky way, but to a galaxy schematic.

#22 bumm

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Posted 19 October 2012 - 07:10 PM

As one who loves the constellations, I've sort of steered clear of this thread too... As near as I can tell, the suggestion here is that we should be viewing and understanding the universe as a whole, and not just objects as found on an artificially constructed map of the sky. That's fine... but I think most all of us with any curiosity proceed to assemble the pieces and gain an understanding of the universe as we enjoy observing it's fragments. While I'm sure you aren't suggesting that the constellations should be left behind as an obsolete artifact of times past, they also are a part of the big picture. While they are only chance patterns of moving stars seen from our particular location and time, they're a part of human history and experience, from the eighteen thousand year old picture of the Pleiades on the cave wall at Lascaux, to the most recent computerized star charts. Most every night, I go out and name all the stars I can, just so I never forget...
Marty

#23 Tony Flanders

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Posted 19 October 2012 - 07:16 PM

I knew I should stay away from this. Starting with the title, "unlearning the constellations".


The title is probably unnecessarily combative. I think "Beyond the Constellations" would be more accurate.

For me, the greatest glory of astronomy is that there are so many different ways to approach it. There had better be! It is, after all, the study of the universe -- literally, everything that is, has been, or ever will be. I find the aesthetic approach, the historical approach, the study of individual objects and stars, and the study of how they fit together, all equally interesting.

#24 FirstSight

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Posted 19 October 2012 - 07:47 PM

For those among us who usually have to put up with mag 5 or lesser skies, a trip to a true mag 7+ gray or black site on a moonless night, especially when the summer Milky Way is ascendant, IS of itself a FORCED lesson in "unlearning" the constellations. It can take awhile before you begin to recognize familiar constellation landmarks because they're lost amid the unfamiliarly dense swarm of visible stars and steamy knots of the indistinct glow of millions of stars too faint to see individually, and the winding dark nebular rivers running in-between the clouds of stars.

#25 auriga

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Posted 19 October 2012 - 08:34 PM

Bruce,
A number of points:

1. Your gifs are great and show a lot about the sky that other representations don't show. I agree with you that these alternative representations of the sky are valuable. Thanks for posting them.

2. You raise very important questions. As far as I can tell, the Herschel 400 I and II, while no doubt valuable and worthwhile, convey little understanding of the structure of our galaxy as a whole. Observing lists in general can have this limitation. So I agree with this part of your thesis as well.

3. The pinhole view is narrow in the sense that one is observing only a small portion of our galaxy. But with my 13 Ethos ( I don't have the 17) in my 16"f/4 Dob the view is perceptually wide, 100 degrees wide. Al Nagler is right about the "grandeur factor." The emotional and perceptual sense of the breadth and vastness of our universe is conveyed in part by these huge visual fields even though in terms of absolute distances they are very narrow indeed.

4. There are some guides in the area of galactic structure. Prime among them, and going far beyond Craig Crossen's Binocular Astronomy, is his subsequent book, with Gerald Rhemann, "Sky Vistas" (published by Springer). He devotes great attention to the structure of our galaxy. Another guide is Bill Tschumy's "Where is M13?" I am sure you are familiar with these but my point is that a huge amount can be learned about the structure and content of our galaxy by careful study of these sources, which you have doubtless already done.

6. If your thesis is that we need to spent time scanning the Milky Way with binoculars, looking for star clouds, dust lanes, dark nebulae, and OB associations, in order to get an understanding of and appreciation for our own beautiful galaxy, I agree entirely.

7. Where I part company with your thesis is as follows: When I look at M17 I enjoy it as an object in itself, but I try also to be aware of where it lies in our galaxy. I value diagrams like "Where is M13" that show it visually. And I devote special attention to objects that are far out toward the Perseus arm, such as the Double Cluster and one or two more distant objects in that direction. I also try to look at objects near the galactic center, such as NGC 6522 and 6528, in Baade's Window, with the realization of where they are; similarly for objects in our Orion Arm. My point here is that viewing individual objects is not exclusive of understanding the galactic structure, and that binocular study, while essential for this purpose, is not the only contributor to this understanding.

Knowing where in our galaxy an object is, adds a great deal to the pleasure of observing it and to my understanding of the object and our galaxy. To know that M54, while not outstanding visually, is probably the core of a now dispersed galaxy, enriches the visual experience.

I am also very interested in viewing the sky in terms of the absolute brightness of the stars in it. So, I always like to take a look at Zeta 2 in Scorpius, and 6231 is itself one of my favorite objects. And Rho in Cassiopeia, and P Cygni, and Wesen and Aludra in Canis Major.

As a related issue, I think the OB associations, especially in Perseus and Scorpius, are much neglected by observers. Perhaps because they are too easy to find and so don't confer much prestige on the observer?

Bill Meyers






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