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General Astronomy >> General Observing and Astronomy

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derangedhermit
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Re: unlearning the constellations new [Re: bassplayer142]
      #5481203 - 10/20/12 11:35 PM

Ref "Where is M13?": it looks interesting, but I do not allow Java to be installed on any PCs I support.

The OP has reiterated a belief in the need to "unlearn the constellations".

I find being specific to be very helpful in clarifying concepts, so:

If we are to discard the current system, it seems fair to ask what we shall use in its place. So, when we stand under the night sky and look up, what identification and navigation system do you propose we use in place of constellations and ancient star names or Greek letters?

Since the OP places Ptolemy's Milky Way description at the top, a great example of the advantages of the new naming and navigational system will be a rendition of the Almagest Book VIII Part II (the description of the Milky Way), and the relevant parts of Book VIII Part I, Ptolemy's listing of stars by constellation, on which that description is based. Can we agree on Toomer's translation, first Princeton Paperback edition (1998), H177-H180 (p.403-404)? Can you now give us a flavor of how that will read using the new system?

Another good test will be an all-sky map to compare and contrast against the ubiquitous Orion DeepMap 600 that corrects the thinking that created it. That will be very useful in understanding the proposal (if all-sky maps are to remain).

Is it so that the very popular S&T Pocket Sky Atlas must also be replaced ASAP?

And any additonal specifics, beyond answers to these questions, on the proposed way forward will be illuminating.


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Crossen
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Re: unlearning the constellations new [Re: Astrodj]
      #5481403 - 10/21/12 04:11 AM

Quote:



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.




My books have been mentioned by a couple contributors to this discussion as good resources for getting a 3-D perpective on the night sky. And in fact the approach you describe here is exactly how I did start in the winter of 1979 in developing what I came to call "Galactic depth perspective." I had decided to study the sky constellation-by-constellaton with 10x50 binocs, Burnham's Celestial Handbook, and the Skalnate Pleso Atlas of the Heavens. I began with Orion and Canis Major, making data lists from Burnham's discussions of individual bright stars and important objects. Then I realized that I could not really absorb the information in these data lists unless I actually memorized them--specifically, the location of the Greek-lettered stars in the constellation, and the magnitudes, distances, and spectral types of the brightest of these stars (Burnham discusses every star of at least mag 3.50). I would run through this data outside at night while actually looking at Orion and Canis Major and soon found myself thinking in terms of the stars' relative distances.

I was very fortunate with where I began (though it was a wretchedly cold Minnesota winter that year) because Orion and Canis Major are good places to start in seeing the night sky in three dimensions. Most of the bright stars in Orion are part of the Orion Association, except for Betelgeuse and Belletrix, which are in the foreground of the Association. And most of the bright stars in southern Canis Major are members of the CMa Association, except for the foreground Epsilon. And Sirius is so much in the foreground of the CMa Association that, by comparison, it seems to be barely beyond the Moon!

And you can easily take the relationship of Orion to Canis Major to the next level of Galactic depth perspective: The CMa Association is both farther from us than the Orion Association and farther "behind" us in that it is roughly toward the direction from which we have come in our orbit around the Center of the Galaxy (galactic longitude 270° in Vela). Thus Orion and Canis Major trace a segment of a spiral arm of our Galaxy. And so by the end of January 1979 I found myself, much to my surprise, already tracing the local spiral structure of the Milky Way.

Much the same approach can be used on the opposite side of the Milky Way, where most of the bright stars from Scorpius on the northeast to Crux on the southwest are part of the much-elongated Scorpio-Centaurus Association. Anybody who has learned the constellations in that 80° length of the Milky Way will have no difficulty at all in envisioning the Sco-Cen Association, nor even in seeing that association's subgroups.

Thus I have found the constellations, old and largely artificial though they be, as useful guides into Galactic astronomy. But I think they are worth learning not merely for their utilitarian value. Most of the 49 constellations we inherited from Graeco-Roman astronomy actually go back to ancient Mesopotamian, and some of these can be reliabily dated (on art-historical and archaeological grounds) to the 5th millennium BC. Thus the constellations preserve the whole history of Western civilization, from its origins in southern Mesopotamia in the 5th millennium BC to European Enlightenment, when Lacaille burdened the sky with small star patterns carrying big names. Would you tear down some of the famous 19th century observatories simply because they have been rendered useless by urban sprawl and its resultant light pollution? I don't think so! The constellations should be thought of in the same way: as part of the heritage of the science we all so much love.

Craig Crossen


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bumm
sage


Reged: 01/07/11

Loc: Iowa
Re: unlearning the constellations new [Re: Crossen]
      #5481707 - 10/21/12 10:39 AM

For what it's worth, some aspects of this thread reminded me of a short chunk of a longer thing I once posted in sci.astro.amateur... I googled it up, and it was in May of 2005.

I looked at the horizon. The Milky Way was probably lying right along it, but I knew I wouldn't see it tonight, especially with that moon... I thought about how the dim Winter Milky Way must be along the horizon behind me. I was sitting upright in the galaxy, swinging in my chair,
heading in the general direction of Vega.
Marty


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magic612
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Re: unlearning the constellations new [Re: Crossen]
      #5481725 - 10/21/12 10:57 AM

A resource that don't recall being mentioned yet is Celestia. Writing code for it, if you are not used to that kind of thing, has a steep learning curve. But there are user-friendly functions that can effectively allow the user to "zoom" in on any part of the sky to see where various objects are in relation to others. Unfortunately, it doesn't provide the distances or other information to the stars. But it is free, an certainly useful if one wishes to "see" the universe with more of a depth-perspective applied to it.

(To get an idea of how it looks, I used it to create some 3-D "zooms" of the Hyades, Pleiades, and Orion's belt stars in a few of my weekly astronomy videos.)


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drollere
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Re: unlearning the constellations new [Re: bassplayer142]
      #5481987 - 10/21/12 01:52 PM

bassplayer, you gave me my first in a *vurrry* long time outright laugh on CN.

the fact that you noticed ... the fact that you were motivated to post by the notice ... the fact that you managed to find the most succinct riposte ... or maybe it's my morning brandy coffee.

anyway ... i owe you one.


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drollere
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Re: unlearning the constellations new [Re: drollere]
      #5482045 - 10/21/12 02:28 PM

auriga stepped up to answer the questions i posted, which will stand for all those who answered on their own.

i have to say that i couldn't answer the questions myself without referring to a reference work -- something i don't have to do to name messier objects, or famous double stars, or distances to galaxy clusters ... which is one aspect of the issue i am raising.

as for auriga's "score"... (2) the sun is headed toward a point south preceding vega, but cygnus is close enough; (3) the nearest "bright" stars are Alpha Centauri AB, Sirius, Procyon, Altair, Fomalhaut, Vega, Pollux, Denebola, Arcturus, Capella, Rasalhague, Alderamin, Castor AB, Caph, theta Centauri, Aldebaran, epsilon Scorpii, Hamal; (4) hipparcos catalogued about 1900 stars within 20 parsecs of the sun, though as auriga says there are many more that we can't see; (7) hyades and beehive are the closest galactic clusters, the "big dipper" is an association (it has no tidal radius, just a common trajectory).

actually, the "orion arm" or spur extends from somewhere in central cygnus all the way past orion and canis major. we are "behind" and somewhat inside this feature in relation to the galactic rotation. the orion nebula is three times farther than the ophiuchus and auriga-taurus star forming regions ... although these are mostly invisible to astronomers using visual scopes. i think orion is the closest one we can easily see.

the last question was a trick question, because i don't know the answer! i'd agree that it's probably in the "backward" direction of the perseus arm; crossan calls out the farthest visible galactic star cluster in that direction. but possibly something in the direction of the galactic nucleus.

in any case, aren't these, taken at face, pretty basic questions? the fact that any of us, as astronomers, would have to look them up is the issue i am pointing to.

speaking of ... crossan's "binocular astronomy" has been mentioned before, but i'll add my strong recommendation. it's a much better balance of history and modern astronomy, and is far more informative about the "big picture", than one finds in burnham jr. ... whom crossan much admires. it has some nice charts (for example, of the SCO-CEN association), but i regret that it doesn't have a little more specific representation of the local bubble and our views in different directions. to a large extent, it still adopts the "flat on the celestial sphere" representation of our galactic viewpoint.

this isn't really crossan's oversight. the spiral arms were not mapped in any detail until the 1970's, and only very recent research has begun to clarify the contours of the gould belt and local bubble -- for example:

http://www.aanda.org/htbin/resolve?bibcode=2003A%26A...411..447LPDF

i think we've accumulated enough research to paint a basic picture. my puzzle is, how? -- which visual features effectively mark the major landscape elements? what *are* the major landscape elements? should we just define them piecemeal, anatomically, or holistically and as examples of galactic dynamics? glenn called out the SCO-CEN association.

i was out last night deploring the feeble milky way appearance at my location. exploring the galactic structure, as has been said, is a dark sky activity, and perhaps more than any other visual pursuit this crystallizes what we lose with light pollution. something like flooding the grand canyon, so we have the electricity for more televisions.


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drollere
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Re: unlearning the constellations new [Re: derangedhermit]
      #5482117 - 10/21/12 03:19 PM

Quote:

If we are to discard the current system, it seems fair to ask what we shall use in its place. So, when we stand under the night sky and look up, what identification and navigation system do you propose we use in place of constellations and ancient star names or Greek letters?




this is the point exactly. i expressed my "puzzle" as ... where to turn among current references as a point of departure and a source of reliable guidance? but the quote defines the bottom line: where is this going, what is the point?

the first topic is that we have a place in a larger structure, and we can see our place in that structure as the milky way. so we should be able to see the milky was as the panorama of a dynamic structure, as having parts in relation to each other and to a common movement, as having points of articulation, as having distances among the parts. a minor but necessary fact here is realization that galaxies are, to a great degree, *transparent* -- we see through the orion spur into the perseus arm, and through both of them to see distant galaxies.

this is to me the database problem: there are galactic clusters and H-II regions throughout the perseus arm or the CAR-SGT arm or the orion spur; these markers can be brought together to outline the direction and anchor remembrance of the distance of these large features. globular clusters can mark the extent of the galactic disk and the approximate distance of its axis. bright, characteristic population II stars can be identified as well.

the second topic is that every spiral galaxy we see is a process, a machine for making stars and star systems. what are the ingredients and steps in this process? this gets to glenn's approach of pointing out the dark clouds and the SCO-CEN OB association. add to that the orion nebula as the intermediate H-II step and to anchor the opposite side of the gould belt; and there should be t tauri stars, other OB associations in cygnus and perseus, some easily seen bok gobules or compact barnard objects, galactic clusters young and old, giant stars, planetary nebulae, and supernova remnants to connect the galactic process to individual star development, element formation and recycling.

the third topic after structure and process would be time: how long the sun takes to revolve the galaxy, how long the sun has existed, the galaxy has existed, how we know these things, etc. but also the local history of our "momentary" place in the local bubble, how it fortuitously gives us long views in critical directions, what might have created it. (there is even a paper that correlates gould belt events with extinction events on earth, via the mechanism of nearby supernovae sending oort belt objects into collision with earth.)

finally, to return to crossan's celebration of antiquity and its lore, i'd think that was a topic i have addressed enough by now. anyone who wants to recount babylonian myths is welcome to it, and nothing said here will deter them. but the stars are empty of social and historical content. there is no reason to wed them eternally to any interpretation. to the extent a new interpretation is looked for, and new features are to be described, then astronomical objects are ready to stand to any purpose.

if humans once indulged the primitive vanity to use the stars to illustrate fictions and myths, then there is no reason humans cannot also adapt them to delineate scientific insights in a way that can better capture the interest of amateur astronomers and our insightful enjoyment of the night sky. there's a time to remember traditions, yes: the problem in this topic seems to be in knowing when to let go.


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The Ardent
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Re: unlearning the constellations new [Re: drollere]
      #5482156 - 10/21/12 03:45 PM

Bruce

I understand your viewpoint and motivations a little bit, being that you are challenging folks to see things a little differently, a little "out of the box"
The problem with unlearning the constellations is that so few astronomers really "know" the constellations. What does "knowing" the constellations really mean anyway?
One of my projects in my quest to "learn" the sky and constellations is to observe all the Flamsteed and Bayer stars of each constellation (where applicable) Why are there some stars in a constellation brighter than the Flamsteeds and Bayers that dont have either designation?

Another excecise is examining the border areas of the constellations and trying to mentally distinguish which stars are in each, when they are so close in the sky. I know the IAU borders arent scientific, but its a fun excerise.

Why dont the stars in Vulpecula look like anything at all?

A problem I have with associations is the lack of reference materials available to the amateur. I can look up individual stars in Skytools, and there may be a note that "this star is a member of the Cepheus OB1" but there are no charts with the associations plotted and member stars listed. I want to be able to observe 10-20 stars of each association and compare them with the field. Other than Sky Catalog 2000 Vol 2 (and thats brief) I havent found anything.

Regards


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auriga
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Reged: 03/02/06

Re: unlearning the constellations new [Re: bassplayer142]
      #5482168 - 10/21/12 03:53 PM

I thought it was obvious: No. 5 can be found by interpolation. (Excel has a program for this.)

For those uninclined to interpolate,

5. As Crossen points out in Sky Vistas, small rich field telescopes can be used as a supplement to binoculars for exploring galactic structure. I have found the Starblast helpful in this regard.

Bill Meyers


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Crossen
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Re: unlearning the constellations new [Re: drollere]
      #5482177 - 10/21/12 03:57 PM

Quote:


crossan's "binocular astronomy" has been mentioned before, but i'll add my strong recommendation. it's a much better balance of history and modern astronomy, and is far more informative about the "big picture", than one finds in burnham jr. ... whom crossan much admires. it has some nice charts (for example, of the SCO-CEN association), but i regret that it doesn't have a little more specific representation of the local bubble and our views in different directions. to a large extent, it still adopts the "flat on the celestial sphere" representation of our galactic viewpoint.

this isn't really crossan's oversight. the spiral arms were not mapped in any detail until the 1970's, and only very recent research has begun to clarify the contours of the gould belt and local bubble




Thank you for the kind words about Binocular Astronomy. You are right about its chapter on the Milky Way: some things in it (though far from everything) are out of date, and I did not cover the far southern Milky Way. (I am of course speaking about the original 1st edition of Binoc Astro: I had nothing to do with the so-called 2nd edition, have not seen it, and therefore cannot say anything about its Milky Way chapter.) That chapter was based upon a 2-part article I published in the July and November 1983 issues of "Astronomy" magazine. However, the Galactic structure material in "Sky Vistas" is up to date. Moreover, it seems quite likely that next year a revision of my 1983 Milky Way article is going to be published and that article will not only have state-of-the-art information on the Milky Way's spiral structure, but cover the far southern Milky Way as well.

Craig Crossen


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Astrodj
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Reged: 08/24/11

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Re: unlearning the constellations new [Re: drollere]
      #5482494 - 10/21/12 06:45 PM

Quote:

the orion nebula is three times farther than the ophiuchus and auriga-taurus star forming regions ... although these are mostly invisible to astronomers using visual scopes. i think orion is the closest one we can easily see.




Just as a point of information...though also mostly invisible visually (especially from Missouri,USA)...

BHR 71, a Bok globule associated with the "Coalsack" (I am intentionally avoiding the use of constellation names to facillitate defining a locale in the galaxy, in the spirit of the thread), and listed in the catalog of southern Bok globules by Bourke, Hyland, & Robinson (1995), is also another nearby star forming region at 150 pc.

Now, would that be located relatively nearby in the Orion arm with us, looking in the direction of the Centaurus Arm?

<edit corrected "closest" to "also another nearby">

Edited by Astrodj (10/21/12 06:53 PM)


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derangedhermit
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Reged: 10/07/09

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Re: unlearning the constellations new [Re: Crossen]
      #5482695 - 10/21/12 09:15 PM

Quote:

My books have been mentioned by a couple contributors to this discussion as good resources for getting a 3-D perpective on the night sky.

Craig Crossen



Is "Sky Vistas" out of print? I can't find it for less than $80. Thanks!


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GlennLeDrew
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Re: unlearning the constellations new [Re: derangedhermit]
      #5482820 - 10/21/12 10:47 PM

Astrodj,
In answer to your last question, yes. At 150pc, it would lie in or near the edge of the Sco-Cen OB association (and is quite likely associated, too), which in turn lies more or less on the inner edge of the Orion-Cygnus arm.


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Astrodj
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Re: unlearning the constellations new [Re: GlennLeDrew]
      #5482968 - 10/22/12 01:03 AM

Glenn,

Okay, I think I see that. Then, if I am understanding correctly, the a fore-mentioned Auriga-Taurus star forming region would be in nearly the opposite direction, about the same distance?

And incidentally, does the Orion arm originate out of (like a spur) the Cygnus arm, with us being fairly near where the two arms diverge, say 1000-1500ly? Representations I can find of our galaxy's arms that name them are ambiguous.

It helps if I visualize our sun as the center of a sphere the size of the galaxy's thickness in our area, with radial spokes heading out in all directions and stopping at different distances. Mentally stretching that distance out(if required), if the direction happens to lie along the plane of the galaxy is easier for me to imagine that way.

Sorry for all the questions, I'm trying to build a better model in my head.


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Crossen
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Re: unlearning the constellations new [Re: derangedhermit]
      #5483065 - 10/22/12 03:51 AM

No, "Sky Vistas" is still very much in print. If you have found it for $80 I think you have done very well. It is an expensive book because its publisher, Springer-Verlag Vienna/New York, chose to print it on extremely high quality glossy paper so the numerous photos by master astrophotographer Gerald Rhemann could be seen at their best.

What is in fact out of print is "Binocular Astronomy" because, as I said, I had nothing to do with the so-called 2nd edition of that book. I've not seen a copy of this 2nd edition, but have been told that its text differs little from that of the original edition. This means that this "2nd edition" is VERY out of date since I wrote the original edition in the mid-1980s!

Craig Crossen


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GlennLeDrew
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Re: unlearning the constellations new [Re: Crossen]
      #5483353 - 10/22/12 10:21 AM

Astrodj,
Our Local arm, Cyg-Ori, is considered a 'minor' arm segment lying between the Sgr and Per arms. It originates at least 3,000 l-y away, in the direction of the Cygnus star cloud, and terminates at perhaps the same distance in Puppis. This is all kind of fuzzy, as I understand it. Spiral arm features are not generally sharply defined, with clear cut edges and termini. In the case of the Cyg-Ori arm, it could be more of a 'flocculent' feature elongated over periods of star formation (Gould's Belt being one such) by differential Galactic rotation, rather than a purely density wave feature.


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Astrodj
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Re: unlearning the constellations new [Re: GlennLeDrew]
      #5483707 - 10/22/12 01:49 PM

Glenn,

That helps, thank you.

To the OP, sorry if I strayed off topic. I probably should have PM'd.


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drollere
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Re: unlearning the constellations new [Re: Astrodj]
      #5485243 - 10/23/12 01:01 PM

not at all, astrodj, your query illustrates the issue. you would have no problem at all answering some factual question about a messier object. or even what messier had for dinner the night he found it. or which mythical creature it is found in. or what babylonian clay retains a picture of it.

Quote:

I understand your viewpoint and motivations a little bit, being that you are challenging folks to see things a little differently, a little "out of the box"



hmmm ... my motivation is that astronomers can be aware at a basic level of where they are and what is around them in their own galaxy. my gif animations, linked in the original post, illustrate that the traditional constellations fail as signposts to the nearest bright stars and to galactic structure.

my other point was that we are "locked in" to the traditional constellations because of the huge library of reference resources that are organized around them. constellations can be useful as basic asterisms to learn one's way around the sky, and as arbitrary patches of celestial real estate. other than that, they are relics.

the fact that we see a dipper (rather than a bear or a plough) or a letter W (instead of a throne) or a teapot (instead of a centaur) in a specific asterism means that the traditional constellations can easily be reinterpreted for other ends. we are free to shape the sky to other didactic purposes, if useful.

rather than a cross, or a swan, cygnus could just as easily be repurposed and taught as a big "X" in the sky that marks the insertion of the orion spur into the sagittarius-carina arm (a very turbulent marriage, btw, one of the richest X ray regions in the galaxy), or vega repurposed as the general direction in which we are headed in the galactic revolution, or the front "T" of scorpius (omitting red antares from the bright white stars) as the heart of the upper scorpius OB association, or the cluster of stars around alpha persei as the core of the perseus OB3 association, or the teapot as pouring hot water on the center of the galaxy.

in the same way that cepheus, cassiopeia, andromeda and perseus all figure in the same mythological story, the progression from the orion nebula to T Tauri to the pleiades to the perseus OB3 to the hyades to the crab nebula can be taught as the natural progression of star creation -- they are all in the same part of the sky! some simple and very basic lore can be held in memory and explained to novices at no harm to anyone else's preferred mythology. those who want to speak of dragons and centaurs, bulls and birds can have at it.

Quote:

Why are there some stars in a constellation brighter than the Flamsteeds and Bayers that dont have either designation?



because in those days everything was done by candlelight. seriously ... flamsteed was an incredibly meticulous and repetitive astrometrician, but there are dozens of "lost" flamsteed stars that he recorded in locations where no star exists. instruments, records, comforts and scholarship were primitive in the 17th century, and mistakes happened.

Quote:

Why dont the stars in Vulpecula look like anything at all?



you can ask the same question about aries, cancer, virgo, pisces, capricorn, cepheus, leo minor, canis minor, lynx and aquarius! the level of "pretend" required here is perhaps why the "pretend" myths that go with the constellations become more digestible. but, to your point, vulpecula is a 17th century "scrap" constellation, invented to use up stars not already in a mythological figure.

Quote:

A problem I have with associations is the lack of reference materials available to the amateur. I can look up individual stars in Skytools, and there may be a note that "this star is a member of the Cepheus OB1" but there are no charts with the associations plotted and member stars listed. I want to be able to observe 10-20 stars of each association and compare them with the field. Other than Sky Catalog 2000 Vol 2 (and thats brief) I havent found anything.



if you are interested in the stars in or out of an association, a paper by DeZeeuw and colleagues, based on hipparcos data, is the basic reference. a more recent paper focuses on the SCO OB2 association specifically:

http://iopscience.iop.org/1538-3881/117/1/354/pdf/980283.web.pdf
http://arxiv.org/abs/0809.0407

incidentally, you would find both papers with the SAO/NASA archive query tool:

http://www.adsabs.harvard.edu/

look up any topic or keywords (author and year of publication is often enough) -- papers you can download as PDF files are coded "F" or "X". you can get really deep into the technical or mathematical weeds with many of the papers here, but you can also find some elegant and recent review or summary papers by a single author.

if you ignore everything but the charts, you'll find the de Zeeuw OB associations shown as individual stars. the problem with the de Zeeuw paper is that everything is shown in galactic coordinates. important to be familiar with and very useful to know immediately where something is in relation to the galactic landscape ... but not the familiar equatorial coordinates.

as a remedy, i use the Dame (2000) microwave map of the milky way as a foundation chart, then add data to it mashup style. for example, in THIS CHART i've added naked eye stars down to v.mag. 4, H-II regions, outlines of the approximate extent of local OB associations, and 50 parsec spheres drawn in perspective to illustrate relative distances. the chart has galactic coordinates marked, so objects in galactic coordinates can be located on the map. and visually it is instructive: the orion arm appears shredded and diffuse, because it is close to us, but the galaxy elsewhere appears dense and compact, because it is far away.

each of us is still on our own if we want to get beyond the constellation constriction. like the binary bias, it's just something you have to recognize on your own terms. if you decide it's worthwhile to look in a different direction, then there are people on CN happy to assist.

so ... my thanks to previous posts that pointed me to references i was unaware of. astronomy is fun because it is an opportunity for continuous learning.


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drollere
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Re: unlearning the constellations [Re: derangedhermit]
      #5485295 - 10/23/12 01:30 PM

Quote:

Ref "Where is M13?": it looks interesting, but I do not allow Java to be installed on any PCs I support.



when i was coming up through the internet, java was going to be the esperanto of the digital age. now even apple won't support it.

Quote:

So, when we stand under the night sky and look up, what identification and navigation system do you propose we use in place of constellations and ancient star names or Greek letters? Since the OP places Ptolemy's Milky Way description at the top ... can you now give us a flavor of how that will read using the new system?



ptolemy represents a floor, not a standard. the point isn't that ptolemy is especially admirable ... it's that he at least saw the milky way as worth looking at, and that nobody since has looked at it with a comparable level of detail. (excepting things like the barnard survey photos ... one can find hundreds of lovely images, but a dearth of explanation of what we are looking at.)

Quote:

Is it so that the very popular S&T Pocket Sky Atlas must also be replaced ASAP?



no, just as it shouldn't be discarded because it does not show the traditional mythological figure overlays (as in every 18th century atlas).

i claim there is a general lack of single and compact resources to anchor the average amateur astronomer's understanding of our place in the galaxy, its broad structure and processes. if we throw out the traditional resources, we're left with nothing. i'd like to stimulate creation, not destruction ... for example, the animations created by "eyes on the sky" (kudos, dude!).


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Re: unlearning the constellations [Re: drollere]
      #5485348 - 10/23/12 01:59 PM

If I understand what I recently read correctly, the next version of Sky Safari will have the capability of viewing the sky as seen from other stars. And I think you may be able to see the motion as to get there at warp speed. I wonder if any of the new planetarium projectors have that capability or if other PC programs such as Stellarium will be able to do it.

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