Naming Omega Centauri and 47 Tuc [Archive]

ngcles

03-09-2007, 12:50 AM

Hi Andrew,

Don't take this as a criticism, just my own view which those who know me, know well. Others see this topic differently and I guess you are all entitled to your own wrong opinions ;-^)).

I have a strongly rooted aversion to creating new "common names" for objects in the night sky. The idea of allocating a "popular name" is almost contradictory to the idea itself. It is akin to inventing a nick-name for yourself. Worse still it can lead to confusion.

How many galaxies are now commonly called the "Pinwheel galaxy" -- four at last count I think, M101, M33, M83 and NGC 2997? Actually, one of the last two is called the "Southern Pinwheel", but I can't remember which one (Case in point)! To add to the mix, then there is the "Pinwheel Nebula" -- M99 which is also a galaxy. This surely is one of the major reasons why we give things a catalogue number so when we communicate with each other, we know _exactly_ what we are each talking about.

I harbor a particularly deep loathing for "common names" that are culture specific. Quite a few of the common names we have become stuck with have been invented in the U.S.A and quite often they refer to a thing quite foreign or unknown to our culture. The excellent planetary nebula NGC 6337in Scorpius is a very good example -- the "Cheerio Nebula" of which I became aware about 15 years ago.

When I saw that name, I thought, what in the hell is a cheerio? It wasn't till they were sold here about 6 years ago that I appreciated the context of the name. An amateur astronomer in Africa or Asia would probably still be in the dark (no pun intended) trying to work out what the name meant.

Another example is the "Toby Jug" nebula -- IC 2220. Some of us will know what a toby jug is, I suspect most won't. It was coined by a couple of Poms at the AAO.

Howabout we start calling things the "nulla-nulla" nebula? (NGC 3199 perhaps) (No, please please, I didn't really suggest that) That'll have the whole world guessing what it looks like!

Even better, we could call _all_ the dark nebulae the "Vegemite Nebula". Sound's right and proper don't it? Then we can argue about whether some should be called the "Marmite nebula".

Burn all common names unless they are _Universally Common_. (Or at least in the context of this hobby "Earthaversally"!)

Having said that, how did the O.C NGC 6231 escape without a moniker I wonder?

Best,

Les D

The laws of Thermodynamics (summarised)

1st Law: You can't win.
2nd Law: You can't break even.
3rd Law: You can't leave the game.

AJames

03-09-2007, 06:54 AM

Les,

My response was more in light of M13, which is commonly known as the "Great Hercules Cluster". Compared to Omega Centauri and 47 Tucanae, this is almost a piddling little globular, ranking merely as the best those lost northerners has to offer.
Whilst I agree that some minor nebulosity or cluster placed in the backwaters of some constellation is probably totally unnecessary to name it, I think that some object that is visible to the naked-eye in the city or urban skyline should get some recognition. As an educator yourself, names are excellent way to portray significant objects in the sky. Such names should at least descriptive of the object or the constellation in which it lies. While I also agree things like the "Cheerio Nebula" means nothing to me personally. [Actual that particular given name also makes me wince every time I hear it. Not only does it remind me of some grand American corporation production line, whose product nutritional value seems questionable. It also conjures up a "happy" nebula.
The naming of stars is systemic of cultures of the ancient world, the Arabic world in the so-called dark ages. The Top 20 stars should certainly have proper names, perhaps even the first 50 or 100. IIS'ers here can read my discussion on that topic at;

http://homepage.mac.com/andjames/Page208.htm

For example, I have been writing some text on the coming opposition of Mars at the end of the year. The text reads;

"Watch out on 10th October, as Mars will form a flat triangle of stars (upside down in southern latitudes) with Mu and Eta Geminorum, whose proper names are Calx and Propus, that shining at 2.9v and 3.2v magnitude, respectively."

Now I ask you... have important are these stars in the scheme of things? They both sound like some sort of pharmaceutical drugs!

Yet, another is Mebsuta or Epsilon Geminorium, which sounds like an African witch doctor or one of James Bond's evil adversaries.

Later the early observational astronomers discovering the inter- and extra- galactic objects, and began naming some of their own discoveries. Ie. The Crab Nebula. Sadly, southern observers mostly missed out, leaving a naming system unbalanced with the mainly euro-centric astrognoists and observers. The boundary of this division is roughly -30 degrees declination where anything below it becomes some foreign backwaters of the sky.
Yet, several did retain names in the south. The Jewel Box, the Magellanic Clouds, the Southern Pleiades, the Gem Nebula, the (yet another) Great Eta Carina Nebula. Probably these two are in the Top 5 of all the fabulous southern deep-sky objects do not even get a shoe-in!
Nevertheless, I stray... The point is that both Omega Centauri and 47 Tucanae are very bright objects visible to the naked-eye that does come up in conversation all the time. I wish had a dollar for every time I've been asked while show the sky and come across Omega Centauri; "Why is it named that?", then having to go through the story of how Ptolemy thought it was a hazy star, but named it as if it were a star, yadda, yadda, yadda etc.!
Perhaps we should do the exact reverse;
Omega Centauri can come the "Piddling Cluster" and 47 Tuc the "Piffling Cluster."
Those northerners wouldn't know what they are missing out on...

My own personal preferences are;

1) The "Omegacent Cluster" - play on words with omega centauri and the word "magnificent", for Omega Centauri. :love:

2) The "Bode Number Cluster" or "Almighty Cluster" for 47 Tuc, respectively - the former referring to the Bode number designation "47" for the cluster. :love:

On the more radical views, and sticking to the Americanised cereal vein, 47 Tuc could be the "Fruit Loop Cluster' - in honour of that great bird Sam the Toucan. Variations on the similar theme could be say the: "Ramphastos Cluster" (the bird species for Sam), the "Tucan Cluster" - Tucan being the Tupi word, meaning "imitative of its call".

:fishing::fishing::fishing:

Note : Perhaps my little joke "The Omnipotent Star Cluster" was a bit too clever, especially when compared to M13 mere "greatness."
This little joke just comes to mind...
"Omega Centauri and the so-called "Great Cluster in Hercules", which reminds me of a good basketball team versus a very poor one, something like the Harlem Globetrotters versus a high school team. If they played together, the score-line would always be something like Omega Centauri 100, Messier 13." :rofl:

Ain't that the truth!

Andrew

ngcles

03-09-2007, 10:57 AM

Hi Andrew,

Yep interesting thoughts.

A few further points arising from your post. I think it a pity that such a noble object such as the Theta Carinae cluster (IC 2602) has to the called the "_Southern_ Pleiades".

Using this train of thought, we could call Omega Centauri "The Southern M13"?? More correctly it should be the other way round of course.

I like the train of thought on the "Fruit Loop" cluster -- NGC 104 or 47 Tucanae. You have referred the "Bode" number, and I might be wrong but I thought it was a Flamsteed number?

Given the splendor of these two objects particularly compared to piddling M13 maybe we could continue the commercial theme by calling them the "Coke" cluster and the "Diet Coke" cluster (I'll leave it up to you as to which is which) -- on the basis that that Coca-Cola claims to be "the real thing"? (they did use that slogan way back when we were lads) We could then call M13 the "Pepsi cluster". Hmmm ... I quite like that idea actually!

Which common name? is another problem. How many common names has M17 got? 3 or 4 I think. But which one is the "commonest" common name? That surely depends where you live to an extent.

The problem with common names for stars is an equally thorny one. Having just written a mass of text and editing the star-maps for someone elses upcoming book you find a similar problem to the object names. Lots of stars bear multiple names, many are highly corrupted and the question becmes "which one is most common?" And is this really a "common" common name? Where do we draw the line? There are also several stars that bear the same name in different constellations.

Additionally so many star names have become so corrupted over time that thay no longer mean what they did originally. They have been translated from Arabic to Greek then from Greek to Latin (or sometimes just latinised Greek) which is later re-translated back into Arabic and anglicised. Result: Something that was originally meant to mean "Most beautiful maiden" now means "My uncles' clubb foot"!

That is where we run into other star names that too make me cringe in disgust like (as we have previously discussed privately) - "Becrux" -- grrrrrr as we well know it is Mimosa. Or Atria -- arrraghhaaaaaa!!!

I could go on longer but I've just run out of stemetil!

Best,

Les D

The laws of Thermodynamics (summarised)

1st Law: You can't win.
2nd Law: You can't break even.
3rd Law: You can't leave the game.

higginsdj

03-09-2007, 11:23 AM

I agree with Les. Lets face it, everyone knows Omega Centauri and 47 Tuc - why do we then need a 'common' name. They seem common enough to me :-)

Cheers

astroron

03-09-2007, 01:50 PM

I hate the "Silver Dollar galaxy" it makes me cringe everytime it is mentioned:mad2: 253 it is and always will be:)

Rob_K

03-09-2007, 02:46 PM

Good discussion, and some good humour on all sides! Just my two bob’s worth, I see a definite place for common names. For some reason, we need to have a name for everything, be it a disease, a plant or a galaxy – to see it and appreciate it is not enough! Proper and ordered nomenclature is necessary in all fields of science including astronomy, but only in science. The natural world is full of wonders, but they don’t belong to science – science is only a construct designed to facilitate our understanding of the environment (everything!) in which we live.

Those dealing in their field with scientific nomenclature on a daily basis have no trouble with Latin, NGC numbers etc. Of course there has and always will be a touch of exclusivism in this – "he who controls the jargon controls the field" – a product of our strange human brains & psyche. But most people need common names.

For the average punter whose interests are fairly shallow and over a wide field of subjects, ordered scientific nomenclature is a pain and actually a barrier to participation. We have descriptive common names for a very good reason, because it is a form of reinforcement in the memorising process. Numbers don’t do this. How many times have you walked around a garden with a group of friends, and one keeps spouting the Latin names till you want to scream "But what the hell is it!!!"? :P

Needless to say, I’m a little troubled by the shortage of common names for our Southern celestial wonders. So in the interests of stirring the pot some more, I suggest "The Great Pearl" for OC and "The Toucan’s Eye" for 47Tuc!! ;)

Cheers -

AJames

03-09-2007, 02:55 PM

:hi: Les,

You wrote;

"I like the train of thought on the "Fruit Loop" cluster -- NGC 104 or 47 Tucanae. You have referred the "Bode" number, and I might be wrong but I thought it was a Flamsteed number?"

As a comment, these numbers are certainly Bode numbers. Flamsteed did his numbering system in 1725, of all naked eye stars as seen from Greenwich, England. The first star in order of Right Ascension in a particular constellation was assigned as 1 followed by 2, 3 etc., despite any other system, until the last one was recorded. This sequence was also applied to stars north of declination -23 degrees, so only the northern constellations were included and a few southern ones. In all, some 2 682 stars have numbers. Highest is 140 Tauri.
Flamsteed numbers today do not follow the true sequence as the slow true movements of the stars over the centuries have change, due to proper motion. For example; 20, 21, 22, 23 Herculis are now 22, 20, 23, 21 Herculis. A number have moved into neighbour constellations. i.e. 34 Vulpeculae that now found within Pegasus.
An example of southern constellation with Flamsteed numbers is northern Centaurus, which has 1, 2, 3 and 4 Centauri - the last two being splendid doubles. Lupus has star 1 and 2. Below this, no Flamsteed numbers exist.
An example of a southern star with a Bode number is p Eridani, which is also 6 Eridani.
These numbers were originally printed with the star catalogue associated with the 1801 version of the original Uranographia. The curse with this is that the numbers remain unavailable in any form and do not appear electronically. The numbers were taken from the observations made from Lacaille's 1752 star positions.
James Dunlop, who had a copy when producing the Paramatta Star Catalogue (PSC), which he used also for his double star catalogue, later used this same numbering system. For example DUN 4 is 100 Phoenicis, DUN 88 is 558 Argus, DUN 173 is 323 Argus, while DUN 204 is 57 Normae etc. Dunlop must have finally dumped the system for those pairs between about 15h and 24h RA, as only 6 of the last 113 doubles have Bode numbers. This is probably because he could not decide in which constellation that each double was placed.
These Bode numbers were eventually dumped completely by the 1840's - (To me) wrongly killed off as "silly" by John Herschel - mainly because it made no practical sense.
Having it today is probably useless anyway, as the boundaries of the constellation did nor follow the rigid RA/Dec boundaries at all and are drawn as huge ovals around them. Worst is constellations like Argo made the stars total just over 1100.

At one time i considered reproducing a kind of "Southern Flamsteed Number Catalogue", but realised it would probably be folly and was not likely to be used by amateurs. it would be fairly easy to do, labelling the stars with a cut-off magnitude of 6.2 - same as Flamsteed - an use the Hipparcos Catalogue to pick them off one by one in increasing R.A.

As for the designation of Roman letters Ie. b Car, J Cen, etc, well that another mess given as a substitute.

Those vaguely interested in star designations might like to read;
"Greek Designations of Southern Stars" - that will fill in the historical gaps here.

http://homepage.mac.com/andjames/Page206.htm

There is also a French translation of Delporte "Demarcation of the Constellations" at; http://homepage.mac.com/andjames/Page207.htm

Regards,
Andrew

AJames

03-09-2007, 10:37 PM

I just had some inspiration...

What do you think of the name for Omega Centauri being also known as
the "Sand Box" or "Sand Box Globular"/

Sand box is appropriate, because most telescopes have trouble fitting in to whole cluster without it spilling over the edges. hen looking through the 'scope it looks like a box of sand. I could be good for kids too, as the could be shown
as picture on the wall and they have to find what is. As kids play in the sand the connection would be clear - and it might help them on the way to imagine their Universe.
:rofl:
AJames

ngcles

03-09-2007, 10:39 PM

Hi Andrew,

Live and learn!

Thanks for that mate, I always thought it was Flamsteed.

Your web page on Greek designations in the southern sky was equally enlightening. Thanks for putting this info on the web for us all -- well done!

Les D

ballaratdragons

03-09-2007, 11:01 PM

I have to admit, I'm dumb when it comes to numbers.

NGC 2546, 583, 5960, etc etc mean nothing to me (I made those numbers up).
Embarrasingly either to the Messier numbers.

But as soon as I read 'Orion Neb', Trifid, Eagle, etc, I know exactly which object it is.

Yeah, there's some I don't like, like Pacman, Cheerio, Silver Dollar etc, but that's the Ozzy in me :lol:

I really find it difficult to remember numbers. In fact I think I only know about 3 or 4 objects by number!!! NGC 4945, 253 and umm . . . M42 :)

Often when I read thru the 'New Posts' I have no idea what image has been posted when it just says 'NGC 3123' or some number. I usually don't bother looking at the thread coz the number doesn't excite me enough to have a look.

But when I see a recognisable name like Trifid, Lagoon, Swan etc (and the 3 or 4 numbers I do know) I open it up and have a look.

I'm getting too old to be fussed learning a few thousand numbers and what they are. Common names often have their place for amatuers and that suits me fine :thumbsup:

My kids remember the common names very easily too. :) When I say 'Eagle', they look for the Eagle.

Also, Omega Centauri, and 47 Tuc sound like common names anyway ;)

ngcles

06-09-2007, 12:51 AM

Hi Ballaratdragons & All,

I can see where you are coming from Ballaratdragons.

I probably didn't make it quite clear enough but the big problem for me is the idea of "inventing" a name. If an object both really deserves one and also really needs one it will happen all by itself. No midwife is needed I think.

By all means keep the names we have (well some of them). Many have important historical value -- for instance M81 which is known as "Bode's Nebula", or ones of ancient standing like Praesepe (M44) -- both of which are inextricably mixed with astronomical history and folklore.

Actually, come to think of it, there is one popular name I am particularly fond of "Blaxendell's Nebula" -- which is probably the only "non-existent object" with a common/popular name. Believe it or not, it is true!.

It is occasionally (humorously) referred to by those in the know as "Blaxendell's unphotographable nebula". It is (allegedly) quite close in the sky to the beautiful golbular cluster M2. There are several reports of it being observed visually, but take a photo and -- no nebula. It is in the NGC as NGC 7088. See the entry at the NGC/IC page:

http://www.ngcic.org/pubdb.htm

I get a giggle every time I think of it.

Many people refer to these sorts of names as "common names" -- and a lot aren't common at all. Not for one solitary instant do I accuse AJ of this -- he has a very high ethic, but there are not a few individuals worldwide who enjoy the sport of inventing a name for a previously unnamed object and then promote it with the aim of promoting themselves -- tacky! Then later there are the petty "motherhood" arguments about:

"I called it that first!"

"No it was me, me, me !!"

etc etc

"Popular names" in themselves are not a real problem -- I would personally would much prefer people to also cite a catalog number alongside the name -- so we can know exactly which pinwheel galaxy they are talking about, have seen, have photographed etc.

And, _no_ culture specific names for me thanks!

Better still, here's a brainwave. Maybe the IAU ought take over the rights to license these popular names and start selling them to the rich and famous to raise money for astronomical research!

We could have the "Rupert Murdoch Nebula" or the "Trump Galaxy"

I wonder what pair of objects Pamela Anderson might be interested in?

Les D

AJames

06-09-2007, 02:47 AM

Les

I do also agree with what you say here. Naming of astronomical objects should convey something to the observer mainly to aid in associating the object to something that might be worthwhile doing. Sadly, as you say, there are often motives behind the naming of objects. Perhaps it doesn't matter, but the essence of the name of Acrux - as an example - was made by the American popularist Burritt who could even see the star from his North American latitude!

Nevertheless, there are so many glaring gaps in the lexicon adopted by the names we use. Frankly, as ballaratdragons says, the common name usage is key to remembering objects that are interesting targets or can guide visual observers to other bright selected targets. The problem for me is that the northern observers have such a plethora of names for northern objects, and that all those below -30 degrees declination almost disappear. This gives the wrong impression that the heavens in the northern sky is better than southern one -which is the crux of my point. Clearly they are not!

However, on the other hand, you don't want too many. It is like recalling the star names. I can remember perhaps thirty or forty names stars immediately, though there are perhaps 160-odd that are legitimate to quote in everyday usage. There are about another 1000 to 1500 that are altogether acceptable, and can be used as anecdotal ancillary names for observational text or nearby new objects. Any amateur observers should really at least know the Top 20, and those with experience should probably be able to even put them in order by magnitude without much problem.

I presume we could debate this ad nauseam, but I do think it is worthy of consideration. Whilst I don't think the "Fruit Loop Globular" will ever be adopted as the given name 47 Tuc - but the humour and levity at least focusses on observing the object, and is diversionary enough to pass the cloudy night away.

When I dreamed up this post, I did so because I thought it might be fun. As an astrognosist at heart (astrognosist is a naked-eye observer of the heaven, under the science prior to the telescope - called astrognosy - sub-classification of astronomy), and I enjoy looking at the night-sky without anything but my eyes and imagination. Indeed living the experience is likely more the fun.
Nonetheless object names might be in the end frivolous, by you may at least have fun dreaming them up with associations of a few degrees of separation as possible - but just don't expect to be famous!

Andrew

1) As too; " I wonder what pair of objects Pamela Anderson might be interested in?" How about the "Umbra Cluster" for the Double Cluster (h & chi) Cluster in Perseus?

2) I forgot M81 was already named the "Bode Nebula"

ngcles

07-09-2007, 12:24 AM

Hi IISers,

Just a few other things to add to this thread that might be interesting to others.

The "name game" is a bit of a roulette wheel it would seem -- if you follow some of the events of history in astronomy. Sometimes it sticks sometimes it can end up in your face.

It is not really widely known that the names of the four major Jovian moons -- the Galilean moons have only relatively recently come the be accepted nomenclature for these bodies.

Take a look at the claim, counter claim and counter, counter claim by Galileo and Simon Marius over who discovered these moons and who got to name them here:

http://en.wikipedia.org/wiki/Galilean_moon

Marius also went on to claim he discovered the Andromeda Spiral (M31) but he was discredited when it became apparent it had been noted centuries earlier by Arab astronomers. The excellent names (actually much better than Galileo's) proposed by the "cheat" Marius were not really accepted until last century (1900s) more than 300 years later.

From Moons we move to the issue of planets and we all know what sort of angst Herschel caused when he proposed the name for his newly discovered planet Georgium Sidus (King George's star) after King George III. Did the annual stipend granted to Herschel by the king have any bearing on his decision. Sacrebleu!!

Then on to constellations and what a tortured web of self-servedness and sycophantic behaviour surrounds this old chestnut. Of the many constellations concocted over the centuries to serve a political purpose, gladly only one remains -- Scutum Sobiescianum which was invented by Johannes Hevelius supposedly to honour King John of Poland for his glorious miliitary victory over the Turks --or was it because said king re-built Hevelius' observatory after it burned down? Hmmm ...

Then there is the case of the great scientist Edmund Halley (who later became "Sir" Edmund Halley) following his invention of the now defunct constellation Robur Carolinium.

Then we have Lacaille -- champion of the concepts small, faint and insignificant who decided to "colour in" just about every gap in the southern sky. But the constellation name game is even older, much older than that!

Witness the three brightest stars in Libra whose names tell of a more ancient home as part of Scorpius. The Romans stole these important stars from Scorpius to invent Libra that was said to represent the qualities of the Roman way -- the good things like balance, fairness, justice, taxation, and crucifixion.

Stars haven't escaped either and the case of how Alpha and Beta Delphini received their monikers is a representitive example and detailed in short here:

http://en.wikipedia.org/wiki/Delphinus_constellation

So, largely as a result of all this skulldugery (and more, much much more)the IAU introduced rules governing the naming of just about everything in the sky.

But one little area has escaped their attention till now ...

This name game is a serious business. For some it has bought fame and money, for others - ignomony.

Best,

Les D

"For my part, I know nothing with any certainty, but the sight of stars makes me dream." -- Vincent van Gogh

ngcles

09-09-2007, 12:40 PM

Hi Andrew & All,

Leaving aside all philosophical arguments over whether these two objects ought to have a popular name (moniker), I have been ponderng what might possibly be fitting for these two "Markque" objects not only of the southern sky, but the whole sky.

Following to some extent the naming of M13 as the "Great Globular Cluster in Hercules", perhaps we ought to use the word "great" connected to the character Centaurus represents -- that quite singular son of a Titan, Chiron? Not only would it be in line with M13s moniker but it points the inquiring mind to consider the constellation's ancient lineage (as indeed the cluster has been known since ancient times).

"Chiron's Great Globular" Perhaps??

As for 47 Tucanae, unfortunately there is nothing in the constellation in which it resides to help, but of course it is pre-eminent of the globulars close to the SCP (there are no others significantly closer to the SCP and warranting the title "great") and so we could have -

"Great Globular Australis" perhaps?

These names are not culture specific, they say something of the magnitude of the cluster and their position and don't sound like "recent inventions" - they have the flavour of the more ancient common names and there is no hint of commercial products -- there go most of my objections.

Just a thought.

Best,

Les D

ballaratdragons

09-09-2007, 02:22 PM

There was an article in AS&T (last year I think) about this exact subject.

How objects have too many names. Some have 4 or 5 classifications!!!!
An 'M' number, an 'NGC', an 'IC', an 'MCG' and a common name. Some other objects use differing catalogue numbers and leave out the more common ones ('M', NGC' etc). Then there are PGC's, SAC's, etc.

Then we get to Star catalogues: SAO, TYC2, GCVS, WDS, BossGC, GSC, HD, BD, CD, CPD, HR, Flamsteed, Bayer, and common names!!!!

How is anyone expected to know what is what up there with so many classifications for each object!!!!!

AJames

09-09-2007, 06:55 PM

Les,

The "Chiron Globular" (or even the "Titan Globular") is even better than my idea. :) As you say, it conjures up a historical connection to the constellation and place Omega Centauri among the great objects of the sky.

To show the relative importance of this debate, I have uploaded a drawing of the relative sizes of the globulars. Clearly the "Great" M13 is really a pip-squeak compared to the main contenders.

In answer to you question and discussion in 07-09-2007 12:24 AM - much of the naming of star for early astronomers were driven also by their Christian or Muslim faith. To remember the star names were driven by venerating God, and in some cases the king, who was right and authority was often to upholding god's law n Earth. The "self-servedness and sycophantic behaviour" as you say was actually sometimes based on the real belief the star and constellation names would sanctify the "glory of God".

The two quote featured in the centres of the great religions were based on;

In the Bible - especially in Psalms 147, 4;
"He determines the number of the stars;
he gives to all of them their names."

In Surah 6, 97 of the Koran says;
"It is He Who maketh the stars (as beacons) for you, that ye may
guide yourselves, with their help, through the dark spaces of land and
sea: We detail Our signs for people who know."

Although, "For some it has bought fame and money, for others - ignominy." For others it was a way of properly venerating their God.

Andrew

Note: There was also at one time a "no naming" policy for some areas of the sky. The southern constellation of Ara for example, was supposed to be one of the alters raised by Moses (some say the Temple of Jerusalem , and was retained against the pagan rituals of the Romans. The story of Ara is one of the oldest, because the constellation in it "H" shape looks like an altar, and that the Milky Way rises out of the southern horizon (from northern latitude) as the "smoke" of the Milky Way rising from the ashes of the fire. According to several sources, Ara was no have no star named because the fires of it hearth were sacred and could only be uttered by God - hence alpha and beta Arae have no given name! :sad:

ngcles

09-09-2007, 10:53 PM

Hi Andrew and All,

Well that is a very interesting (and plausible) explanation of why Ara has no named stars. Due to precession Ara was even higher in the sky in classical times than now. As I mentioned earlier, I recently wrote some text for an upcoming book and a section of it related to mythology of the constellations and Ara (being a southern one) fell to me.

I think you noted it was an altar built by Moses, but I think in fact is was an altar built by Abraham to sacrifice his son Issac. But there are other "sacred connections" too. To reproduce a small section of the text:

"The Hebrews interpreted the stars of Ara as either the altar Noah built after surviving the flood, or as the one God ordered Abraham to build to sacrifice his only son Isaac upon.

The Greeks saw it as the altar where the gods swore their allegiance to overthrow the Titans and to the Romans, it was an altar where incense was burned for the dead. In some of the early “modern” sky-atlases, Centaurus is depicted carrying the carcass of Lupus the wolf on a sword or spear in the direction of Ara, apparently for sacrificial burning. There is however no mythological history to support that picture. If the portrayal were accurate, Lacaille ruined it when used a blank space between the three constellations to create Norma, the level and square — an odd obstacle for Chiron to traverse on his way! "

Sorry all, I couldn't resist the temptation to have yet another dig at Lacaille!

I also noted later in that piece that there were no named stars but didn't realise why. Thanks Andrew for filling in that blank, though it is too late to add to the text.

The "Titan cluster" I don't think quite (mythologically) fits. Chiron the centaur was the son of Cronos (a Titan). Cronos assumed the form of a horse and then seduced the nymph Philyra. That made Chiron immortal, but _not a god_ (a Titan in this case) I think.

In fact Chiron was placed in the sky by Zeus at the plea of Heracles (Roman "Hercules") -- If Chiron was a Titan this would be a strange act as the Olympian Gods had previously overthrown the Titans and they were afterward imprisioned in Tartarus.

Re the religious overtones to star names, yep certainly true. Though very few Hebrew star names survive that I know of -- the Arab ones (pre Muhammad) on the other hand are very common. No christian ones that I know of off the top of my head.

A better (astronomical) biblical verse to consider is Psalm 19 v 1-4:

The heavens declare the glory of God;

the skies proclaim the work of his hands.

Day after day they pour forth speech;

night after night they display knowledge.

There is no speech or language

where their voice is not heard.

Their voice goes out into all the earth,

their words to the ends of the world.

Is the above evidence of 11th commandment:

"Thou shalt listen to the knowledge of the stars?"

For us, this is the easiest to follow!

Best,

Les D

AJames

10-09-2007, 12:58 AM

Les,

I think the story of Abraham about has been proven as a myth about Ara, and is likely a fairly modern invention.
It was John Baptist Riccioli who was one of the principal writers who attempted through his theology, to write on the connect of God and constellations. This appears in the two-volume "Almagestum novum" (1665) written by him and the physicist Francesco Maria Grimald - who contributed much to the lunar work in this 15th Century publication. I have read a translation of this work, mainly for his work on double stars - especially Mizar in Ursa Major but I would have to look throught the copy to find the exact source. The Latin version of the whole book can be read at the;
http://fermi.imss.fi.it/rd/bdv?/bdviewer/bid=000000300870
The Ara text comes from the chapter entitled "Liber sextus de Stellis Fixis" ?(I think)

This association is also mentioned briefly in Allen's (1899) work, stating;
"...said that Ara represented one of the alters raised by Moses, or the permanent golden one of the Temple in Jerusalem; but others of the biblical school consider the Altar of Noah; erected after the deluge."
[His words in Bold]

The quote of this latter version here. appears in Genesis 8, 20;
"Then Noah built an altar to the LORD, and took of every clean animal and of every clean bird, and offered burnt offerings on the altar."

I think Krupp, I can't recall where, said that the Abraham / Isaac story related to Ara could not be confirmed by him.

As for "No christian ones that I know of off the top of my head." Certainly their weren't many, as nearly all of them reflected the names of the virtues. As they didn't know the names of the stars historically (that God knew) they reasoned they would have been named after the cardinal virtues. Ie, Those of the four bright stars of the Southern Cross were, or as Baron von Humboldt called them, Justice, prudence, fortitude and temperance

As to the 'Christianisation of the sky', perhaps the most bold of all was Julius Schiller (15??- 1627), who produced his 'Coelum Stellatum Chistianum', where he renamed all the constellation after Biblical artefacts, events or people. For example, Taurus became St Andrew, Cruci Christi as Cygnus, and even Andromeda was to be "The Sepulcher of Christ". His figures were taken from the New Testament for the northern hemisphere and the figures from the Old Testament for the southern hemisphere - and in this star atlas, Ara was the altar of Noah.

As for Omega Cen You also said; "The Titan cluster" I don't think quite (mythologically) fits.[/I]" Nor do I, but it certainly a better name to counter the fallacy of the "Great Cluster in Hercules" - even if it isn't mythologically correct!

Andrew

AJames

10-09-2007, 02:43 PM

Les and all,

In last last post I had assumed that the story was common. Ara is the Altar of Noah, and the ship of Argo was thus modified to become the ark. The story was extended with the attempt to bring the dove which was used to find land. This became the constellation of Columba Noae (Noah's dove), which is now the modern constellation of Columba.

Furthermore the grand ship of Argo, with Jason and his accompanying shipmates, was deem important and probably come about during ancient times where from southern coast of the Mediterranean Sea during winter then into the northern spring as the ship sat on the southern horizon. The ship stood almost upright, being held in place and floating on the long curvature of the Milky Way - a rough milky sea, which is lowest between modern day Crux and southern Carina.

Aratos in his "Phaenomena" - the story of the constellations produced around 270 BC, writes about Ara and the region looking like ; :astron:

"Below the fiery sting of the dread monster, Scorpion, and near the South is hung the Altar. Brief is the space thou wilt behold it above the horizon: for it rises over against Arcturus. High runs the path of Arcturus, but sooner passes the Altar to the western sea. But that Altar even beyond aught else hath ancient Night, weeping the woe of men, set to be a mighty sign of storm at sea. For ships in trouble pain her heart, and other signs in other quarters she kindles in sorrow for mariners, storm-buffeted at sea. Wherefore I bid thee pray, when in the open sea, that that constellation wrapt in clouds appear not amidst the others in the heavens, herself unclouded and resplendent but banked above with billowing clouds, as often it is beset when the autumn wind drives them back. For often Night herself reveals this sign, also, for the South Wind in her kindness to toiling sailors. If they heed her favouring signs and quickly lighten their craft and set all in order, on a sudden lo! their task is easier: but if from on high a dread gust of wind smite their ship, all unforeseen, and throw in turmoil all the sails, sometimes they make their voyage all beneath the waves, but at other times, if they win by their prayers Zeus to their aid, and the might of the north wind pass in lightning, after much toil they yet again see each other on the ship. But at this sign fear the South Wind, until thou see'st the North Wind come with lightning. But if the shoulder of Centaur is as far from the western as from the eastern sea, and a faint mist veils it, while behind Night kindles like signs of storm upon the gleaming Altar, thou must not look for the South, but bethink thee of an East Wind."

Of Argo he writes;

"Beside the tail of the Great Dog the ship Argo is hauled stern-foremost. For not hers is the proper course of a ship in motion, but she is borne backwards, reversed even as real ships, when alread the sailors turn the stern to the land as the enter the haven, and every one back-paddles the ship, but she rushing sternward lays hold of the shore. Even so is the Argo of Jason borne along stern-foremost. Partly in mist is she borne along, and starless from her prow even to her mast, but the hull is wholly
wreathed in light. Loosed is her Rudder and is set beneath the hind feet of the Dog, as he runs in front."

Later he says of both constellations;

"Nor do Perseus and the end of the stern of jewelled Argo remain on high, but Perseus sets all save his knee and right foot and Argo is gone save
her curved stern. She sinks wholly at the rising of Aegoceros, when Procyon sets too, and there rise the Bird and the Eagle and the gems of the winged Arrow and the sacred Altar, that is established in the South."

Andrew

I love the images this this conjures up. I can almost see Johnny Deep standing on the poop deck like in the "Pirates of the Caribbean" with the storm raging.

Harrrr Me Miserable Hearties! ;)

Stevo69

11-09-2007, 04:37 PM

I agree, why couldn't the IC catalogue numbers just continue on from the NGC numbers? Why does a Messier object get an NGC number? Why do people have to complicate things?

A case in point is the Caldwell catalogue. As much as I admire an respect Patrick Moore, why did he have to make a whole new catalogue? Well, I know his reason for it, that's commonly known. All these different catalouges, i feel, just make life more complicated!

hoo roo

Steve

glenc

12-09-2007, 09:08 AM

I am not a great fan of renaming/renumbering objects (e.g. Caldwell) but I don't mind if they are named after the person who found them or if they are given a name based on their appearance.
Omega Cen was found by Halley in 1677 and 47 Tuc was found by Lacaille in 1751. Maybe we could call them Halley's Great Globular Cluster and Lacaille's Great Globular Cluster. (I use the word great because they both found other globular clusters.)
http://www.seds.org/messier/xtra/history/dis-tab.html

ngcles

12-09-2007, 07:00 PM

Hi All,

I very, very much like Glen C's suggestion. It removes any objection I could possibly think of save perhaps one. Halley was also the discoverer of M13 (that other "great" globular) -- he was certainly the first one to place it in a catalogue. When the people see the title, they might be inclined to confuse it with M13. The announcement of Omega Centauri (NGC 5139) is in the same catalogue.

http://seds.lpl.arizona.edu/messier/xtra/similar/halley_pt.html

As for the NGC/IC etc etc, I believe Dryer in compiling the NGC set out with the intention of consolidating all discoveries into one catalogue. He leaned heavily on Herschel's "general catalogue". I think Dryer tried to make one "be-all-and-end-all" master list that would include everything that guys like Messier, Lacaille, Dunlop, Herschel(s) etc etc.

He arranged the NGC basically in RA order starting at 0hrs as it was at his epoch (1900?? -- I'm not certain). Eg NGC 1 is in Pegasus. It is now at 0hrs 7mins due to precession.

Because it is arranged in RA it is impossible to add to without ruining the scheme. Just a few years later when the additions and errors had to be cleared up they then published those in a supplement -- The first IC (also arranged at least mostly in RA order) and then a second supplement as the pace of discovery increased.

The other catalogues came out mainly as a result of survey work becoming deeper and deeper and then finally being all done photographically. There are several more specialised catalogues that list things like "flat galaxies" and then "peculiar galaxies" (Arp) for those who just want to investigate special classes and sub-classes of things. Some very small "catalogues" arise because someone publishes a paper about say two new discoveries. Sometimes mistakes are made and a previously discovered object like the G.C NGC 6717 was included as Palomar 9 in the Palomar list of new G.Cs.

But I do agree with you it can be confusing. There is a convention (at least among professional astronomers) as to how they cite when a paper is published in the ApJs for example. I can't remember off the top of my head how it works but it basically amounts to "cite the most commonly used catalogue first".

It would be great if we had a naming scheme like the biologists use that grouped "like objects" together in a hierarchy, and where the name also conveyed something about the object. But I think it's too late now ...

Les D

AJames

12-09-2007, 08:29 PM

No No No No No.... (with operatic overtones)

Halley and Lacaille, although the observers and discoverers of both these objects, the did not really disclose what they were.

1) Edmond said in 1677 that Omega Centauri was just a "luminous spot or patch in Centaurus" - no mention of stars anywhere. It was actually Ptolemy who discovered that the area was the "nebula on the back of the horse" - dorso Equino Nebulous. Halley added virtually nothing to what we know of this object. We could name it Ptolemy's cluster - but that is reserved for M7!

2) As for Lacaille - Abbe to his mates - at least had a telescope when he viewed 47 Tuc in 1751. He named it numero one in his catalogue, but he said;"It resembles the nucleus of a fairly bright small comet" - placing it under nebulolisities not accompanied by any star visible in a telescope of two feet. Lacaille didn't even name it 47 Tuc - Bode did that sometime later.

Halley claim for this "deep-sky discovery" is in my opinion just totally bunkum, with Lacaille's not far behind.

Indeed, it was very probably James Dunlop who first reported both these objects as being a star cluster and stellar in nature - though certainly both were observed using larger telescopes in somewhere between 1751 and 1820.

No! (with titanic and emphatic connotations) The name of the object should fit the description named by southerners for southerners - and not just on some trumped-up discoverer under very dubious circumstances. These deep-sky supremos of their class, size and in the Top 10 of the deep-sky objects.

When you read statements like;

"Messier 13 (M13, NGC 6205), also called the 'Great globular cluster in Hercules', is one of the most prominent and best known globulars of the Northern celestial hemisphere."

[ See http://seds.org/messier/m/m013.html ]

It makes no mention of the larger and brighter southern examples.

...but do in my mind keep coming back to the Rev. T. Webb :prey: :prey: :prey: :prey:;

"The mere aspect of this stupendous aggregation is indeed enough t make the mind shrink with a sense of the insignificance of our little world. Yet the Christian will not forget that, as it has been nobly said, He took of the dust of this Earth, and with it he rules the universe!"

... but had the Rev seen Omega Centauri he would have needed a bottle of whisky, two bullets and a gun; then take a strong sedative just to calm him down!

As for 47 Tuc, it finally took R.T.A. Innes in 1896 to start balancing the ledger against the heavily weighted northern bias. He describes the true nature of 47 Tuc, he called;

"Most glorious globular cluster, stupendous object, completely insulated, stars all 12th to 14th magnitude. Central blaze ruddy, rest white."

If little pip-squeak M13 is a "superb globular", then what are these two southern deep-sky gems that meet their magnificence?

Where not just talking about some little piddling objects here! :bashcomp:

Stevo69

12-09-2007, 10:09 PM

Yes Les, I think Dreyer was trying to do the "right thing". And in most, I think he succeeded. But who started the IC catalogue? why couldn't they continue adding onto the end of the NGC.

I guess everyone who comes along in history believes their catalogue and nomenclature will be the definitive in their time, and presumably into the future. (mmm, I might start my own catalogue!!)

I agree with naming such as Omega Centauri, but I can stare at images of the 'Eagle Nebula' for hours and I still cannot see an eagle! My point is that naming an object by what shape it depicts can be very subjective, from the point of view of the observer. If sombrero hats were not as popular outside the Americas, would we feel as comfortable with the 'alternative' name for M104?

hoo roo, Steve

glenc

13-09-2007, 06:26 AM

Andrew, they did see them as "deep sky" objects not just stars. Should we require that they resolve them? And thanks Andrew for starting an interesting thread. Les, as you said, M13 is not Halley's greatest globular, it is the 8th brightest glob in the sky.

Gargoyle_Steve

15-09-2007, 03:05 AM

After looking at Omega Cent through 20x80 bino's several times it reminds me of a wayward golfball, sitting on the dark coloured bottom of the creek. I know it isn't a historical, mythical or even a inspiring name but I sometimes refer to it in the privacy of my own head as the Golfball Cluster - it is the only cluster I've seen through bino's that is both large enough and of sufficient density and distribution of it's stars as to give the impression of being a solid ball when viewed that way.

Glen .. if there is another cluster around with similar attributes I'm sure that you'll know it - feel free to correct me if I'm wrong mate! ;)

glenc

15-09-2007, 06:22 AM

Steve it does look like a golf ball in 20x80s but I prefer a historical name.
People get credit when they find comets, but not when they find DSO.
Maybe we could call omega Cen Halley's best globular. 47 Tuc is Lacaille's best globular and M83 is Lacaille's (only) galaxy.
Lacaille found a galaxy with a 0.5" refractor, that deserves some credit. :eyepop:

Argonavis

15-09-2007, 09:04 AM

Herschel in 1855 refers to "superb globular cluster, No 47, Toucani of Bode...one of the finest objects of this kind in the heavens."

with this sort of provinence, why would you rename it?

It was listed by Bode in his catalogue of 1801, which is a separate work to his Atlas "Uranographia" of the same year.

There is only one other spectacular southern object that I know of whose designation has survived from Bodes catalogue - 30 Doradus, otherwise known as the Tarantula Nebula.

glenc

17-09-2007, 08:40 AM

Halleys' Superb Globular (omega Cen) and Lacaille's Superb Globular (47 Tuc)?

OneOfOne

17-09-2007, 08:53 AM

I personally have always liked what they call it on my Celestron GoTo menu, Omega Cluster, which could be interpreted as "The Final Cluster", or "The Last Cluster". The name sums it up pretty well being the largest, and greatest.

Don't know about 47Tuc though...still thinking.

AJames

18-09-2007, 07:53 AM

Argonavis said - and these are my replies;

"Herschel in 1855 refers to "superb globular cluster, No 47, Toucani of Bode...one of the finest objects of this kind in the heavens." with this sort of provinence, why would you rename it?"
* "provinence". Do you mean providence or prominence? I've presumed the former.

While John Herschel did write this, it was during the time when he was reflecting on his observational endeavours of his father. However, although Herschel didn't give it a name doesn't exclude the possibility of giving them proper names. This issue is necessary because most northerners could care less about objects they can't see. 47 Tuc's declination makes it an unworthy target to about +15 degrees latitude - well away from the traditional population centres of the world - and its is really this reason for the neglect.

"It was listed by Bode in his catalogue of 1801, which is a separate work to his Atlas "Uranographia" of the same year."

Yes, this is true. However, but both were actually intended to be together. The catalogue was a validation of its worth, but he knew the popular part of his work was the atlas which was - along with the newer editions that were to come - his money making and enduring endeavour. Furthermore, the catalogue was a star catalogue and not a deep-sky one. I think it is confusing to label deep-sky objects as stars - even if this is historical the case. Ie. We don't call M22 by its Flamsteed Number do we?

"There is only one other spectacular southern object that I know of whose designation has survived from Bodes catalogue - 30 Doradus, otherwise known as the Tarantula Nebula."

I was very surprised you quoted this as an example, because it actually validates the whole gist of the argument. If 30 Doradus is also known as the Tarantula Nebula, then why aren't 47 Tuc and Omega Centauri given the same treatment - especially if they are significantly brighter and more prominent?

[Note: Another the magnificent northern example is h and chi Persei, two actual open star clusters known as the "Double Cluster of Perseus". chi Persei is listed as the Flamsteed star, 6 Per, even though it is nearly always is referred to as the star cluster, NGC 869. However, fainter h Persei, which is the brightest star of companion cluster NGC 884, has no Flamsteed number.
Actually both clusters are actually officially recognised as the "Chi Persei Cluster" - another example of the frankly bizarre nomenclature / naming system - but the point is - why give star names to objects that are clearly star clusters with many stars or even known nebulae which are so visually different?
Yet, after all this, what do nearly every northerner commonly call this... "Double Cluster of Perseus"! ]

No! I think as southern observers who are impressed with the magnificent bright objects in our southern skies should be OBLIGED to use proper names.

Comment : Let's just say your avatar here of "Argonavis" portrays something useful that is actually relating you. Would you instead prefer your ABN number (Australian Business Number) instead and even just the non-descriptor of "Hey You"? :cold: Shouldn't we apply similar precepts to the best deep-sky objects, and say, for arguments sake, also the Top 100 stars in the sky?

I do intend to make an additional statement on bringing proper names into common usage in due time... :o

AJames

18-09-2007, 08:24 AM

Glenn,

I do at heart agree with this.

However, I do have reservations with "Halley's Superb Globular". It concerns me as a misnomer. This is because it was Bayer who listed it omega centauri in the first place - prior to Halley, while to true discoverer of this "hazy" object was Mr. Ptolemy. [Just because his observations were fraudulently obtained, should we dismiss his contribution? Sadly we cannot CSI-like prove that Mr. Hipparchos was the original observer - as this document is lost to history. Yet you would expect with this Rhodes observers eye to detail, that omega cen was certainly visible.

Both names you suggest here are worthy contenders for the crown...

How about just ;

"Omega the Magnificent" -
Omega le magnifique

:jump:

Andrew :driving: :mad2: :scared3:

NOTE: Personally, and without any malice to you, these given names I think still somehow lack the necessary "oomph" that really sets them apart . Though I know that the real use of some other superlative(s) or some (im)proper adjective here is always esoteric at best - and will always be hard to agree on.

AJames

18-09-2007, 08:54 AM

I showed a picture of Omega Centauri to one of my mates, who is not actually interested in astronomy, (surely the ultimate oxymoron). He immediately suggested the "Penthouse Cluster." Shocked, at first I thought he was referring to the popular R-rated magazine, and my mind flashed too, well... :innocent:. However, what he was referring to the creme de la creme of a residential building - which is at the top and closest to the heavens. Huuummmn... I though... Oh for a ziggurat !!! :eek:
This got me thinking - "The Ziggurat Cluster"

Definition: From the middle-eastern word of ziqqurratu. A rectangular stepped tower, sometimes surmounted by a temple. Ziggurats are first attested in the late 3rd millennium BC by the Akkadians and probably inspired the biblical story of the Tower of Babel (Gen. 11:1–9).

Reaching up to Heaven indeed! Surely, even Ptolemy would be pleased! :ship1:

AJames

18-09-2007, 09:15 AM

Celestial Urania
Thy wonders we would know -
Those mysteries and marvels which
Alone inspire us so
That nightly from this Earthly sphere
We try to comprehend
Thy Universe as infinite,
And ages without end.

O beautiful Urania,
As thus we look afar,
And night across the awful gulf
Between us and that star
Which we have all found of all thy host
The nearest one to be
How can we then but stand appalled
By thy profundity?

O Heavenly Urania
In numberless array
Thy suns and system scintillate
Throughout the vast display,
The clusters and the nebulae,
The Galaxy and all,
But midst this cosmic throng appears
Our world, remote and small!

Celestial Urania
With thee can nought compare
Thy magnitudes transcend all thought,
Thy view sublimely fair;
O heavenly Urania,
Be ever this our aim:
To love, serve, honour, study thee -
Thy Science to proclaim.

Frederick Charles Leonard
J.RAS.C. October, 1923

:earth:

glenc

18-09-2007, 11:02 AM

The question is should we give credit to the first one who saw them as stars, or to the first one who saw them as DSO or to the first one who saw them as globulars?

Dunlop's 1826 descriptions are:
D18 (47 Toucan, Bode.) This is a beautiful large round nebula, about 8' diameter, very gradually condensed to the centre. This beautiful globe of light is easily resolvable into stars of a dusky colour. The compression to the centre is very great, and the stars are considerably scattered south preceding and north following. - Figure 1 is a good representation. 8 observations

D440 Omega Centauri (Bode) is a beautiful large bright round nebula, about 10' or 12' diameter; easily resolvable to the very centre; it is a beautiful globe of stars very gradually and moderately compressed to the centre; the stars are rather scattered preceding and following, and the greatest condensation is rather north of the centre: the stars are of slightly mixed magnitudes, of a white colour. This is the largest bright nebula in the southern hemisphere. 8 observations

AJames

18-09-2007, 03:34 PM

Glenn, let me get this right...

You said;
"The question is should we give credit to the first one who saw them as stars, or to the first one who saw them as DSO or to the first one who saw them as globulars?"

Omega Centauri
1. Ptolemy (stars) - then Halley
2. John Dunlop
3. John Herschel

47 Tuc
1. Lacaille
2. John Dunlop
3. John Herschel

Reasoning.
Omega
1. Ptolemy saw this as a "hazy lucid spot"
2. Dunlop first resolved the stars
3. John Herschel first to separated the globulars from the open clusters

47 Tuc
Omega
1. Lacaille saw this as a "hazy lucid spot"
2. Dunlop first resolved the stars
3. John Herschel first to separated the globulars from the open clusters

Andrew

glenc

18-09-2007, 04:26 PM

I would give credit to the first to see it as a "Deep Sky Object", not just a star.
James Dunlop saw omega as a "beautiful globe of stars". He saw it as a globe and as stars, does that mean globular?

AJames

18-09-2007, 05:20 PM

Glen

Yes, Dunlop did describe the stars as a globe, but the term only meant as a cluster of stars not a globular star cluster per se. I.e. All the star clusters were viewed as the same. I think you will find that the word "globular cluster" is a far more modern invention.

According to some, the true "globular" classification was by John Herschel in "Catalogue of Nebulae and Clusters of Stars" the Royal Phil.Trans., 154, 1 (1864). However, others say it was the 3rd Earl William Parsons Rosse around 1845, who began to resolve the cores, and revealed the tens of thousands more stars than any open cluster. Needles to say, the first written term was John Herschel.

The main reason was NOT that globulars looked different from the open clusters, but because they were relatively so rare objects. After Dunlop, 49 were known, and most of them remained either unresolved or poorly examined. This had only increased to 56 in 1840, and even the NGC in 1888 listed only 66.

The "real killer" for globulars came with the first observations of variable stars, which showed that the distances of these objects were away from us - anagalactic distances and not within the nearby arms of the Galaxy like the open clusters.

"Globular Day", if one was ever to be recognised, is the 18th May 1860. This was when Arthur Auwers discovered the nova in globular M80. Peaking at 6.7 magnitude, it remained at this magnitude for three days, only to eventually fading beyond telescope view on the 16 June 1860 around 11th or 12th magnitude. Its intrinsic brightness, if it was indeed associated with the cluster, suggested these objects were perhaps fundamentally quite differ-
ent from the open clusters. Until 2007, the only other galactic globular nova that we have observed was within NGC 6553 (V1148 Sgr) in 1945.

The first of the regular globular variables were casually discovered in 1881, and the first of the important RR Lyrae pulsating variables was by Solon Bailey in 1895. In our far southern skies, the first variables were found in Omega Centauri by Pickering in 1893 and 47 Tucanae by Bailey in 1902.

It was Harlow Shapley between 1916 and 1918 who cemented globulars as separated types, finding the old RR Lyrae variable stars and using them to establish they were many kiloparsec distances. Walter Baade eventually used globulars in 1944, and determined the fundamental distinction between the Population I and II stars within the Milky Way Galaxy. This became the key. The ages of globulars were much older than the typical brighter stars seen in the Galaxy.

This finally killed and severed the old links between globulars and open clusters. :sadeyes:

Andrew

ngcles

18-09-2007, 09:16 PM

Hi All,

Well, this has all been very interesting and the divergence of opinion on the subject begs the question of whether any consensus can be reached. But even if it can be reached here will any proposed names then reach wide acceptance?

My attitude (for what little it is worth) on the subject is known from the beginning of the thread. But, I am at least cheered by the fact that there seems to be a leaning towards a name(s) that somehow tie in the historical aspect and/or a descriptor that will still be "sensible" in a couple of hundred years.

How will people react in 100 years time to names like the "CBS eye" for NGC 3242 -- more widely known as the "Ghost of Jupiter", or "Cheerio Nebula" for NGC 6337, or the "Pacman nebula" for NGC 281, the "Cheeseburger nebula" for NGC 7026 or ... Yuk, Yuk, YUK! I've been waiting with bated breath (not) for the "Twinkie nebula" and the "Coke nebula"

I'm still happy with Omega Centauri. But I also hear a lot of people call it "Omega CentauRUS" which also makes me **cringe**. I'm also happy with 47 Tucanae at present. But, I happened to already have the glue out and after reading some of the responses above I thought, how about "Chiron's Superb Globular" for NGC 5139 -- which kills the Halley/Ptolemy sticking point and it has just a hint (a bare hint admittedly) of alliteration to it?

And for 47 Tucanae (NGC 104) we need something a little different but with no less "gravity" -- how's about "Stupenda Australis" or simply "La Stupenda"?? Joan Sutherland (not that I'm and Opera fan at all) was known as "La Stupenda" in the opera world. Just a thought. Seems fitting enough. What's the connection between Joan Sutherland and 47 Tucanae? None at all -- Stupenda just kinda fits as a descriptor and it's close sounding enough to superb. but doesn't sound glitzy like "the stupendous cluster/globular". Maybe it's just a "stupider" idea!

Golf Ball? -- please noooooooooooooo!

Re: the novae in globulars, Andrew I think M14 had a nova, but I guess it wasn't "observed" in the strictest sense because it was only discovered 26 year later when someone noticed in on a plate taken by Hogg in 1938.

http://seds.lpl.arizona.edu/messier/m/m014.html (http://seds.lpl.arizona.edu/messier/m/m014.html)

Best,

Les D

Mrs. Schroedinger to Mr. Schroedinger:
"What in the hell did you do to the cat? It looks half dead!"

glenc

19-09-2007, 03:23 AM

RE: Halley's Gigantic Globular = omega Cen
I don't think we should credit Ptolemy with seeing omega Cen as a DSO.

Omega Centauri had been listed in Ptolemy's catalog as a star. Halley was the first to document its nonstellar nature, and listed it as "luminous spot or patch in Centaurus" in his historical list (http://seds.org/messier/xtra/history/deepskyd.html) of six such objects.
http://seds.org/messier/xtra/ngc/n5139.html

Ptolemy saw four DSO and discovered two of these DSO, M7 and the Coma cluster. http://seds.org/messier/xtra/histlist/histDis.html

This splendid cluster (M7) was known to Ptolemy (http://seds.org/messier/xtra/Bios/ptolemy.html), who mentioned it about 130 AD and described it as the "nebula following the sting of Scorpius." The description may also include M6 (http://seds.org/messier/m/m006.html), but this is uncertain. Because of this presumable discovery, the present author [Hartmut Frommert (http://www.seds.org/%7Espider/)] has proposed the name "Ptolemy's Cluster" for M7 some years ago, a proposition which has found some acceptance meanwhile.
http://seds.org/messier/m/m007.html

This large and conspicuous (Coma) cluster was first cataloged by Ptolemy; it is scattered over an area of about 4.5 degrees diameter. Although conspicuous, it was neither included in Messier's nor in the NGC catalog, because its nature as a true, physical cluster was proven only in 1938 by R.J. Trumpler who identified 37 stars as true cluster members. Prior to this, P.J. Melotte had cataloged it in his 1915 catalog (http://seds.org/messier/xtra/supp/cats.html#mel) as No. 111. http://seds.org/messier/xtra/ngc/mel111.html

RE: Lacaille's Grand Globular = 47 Tuc
As its name "47 Tucanae" indicates, this object was first cataloged as a star and numbered the 47th in Tucana. Although a conspicuous naked-eye object, it is situated so much south at its declination of -72 deg, that it was not discovered as a deepsky object before 1751, when Abbe Lacaille (http://seds.org/messier/xtra/Bios/lacaille.html) cataloged it in his list of southern nebulous objects (http://seds.org/messier/xtra/history/lacaille.html).
http://seds.org/messier/xtra/ngc/n0104.html

When I say Lacaille's Globular I mean he found it and we NOW know it is a globular, but he didn't know that.

No doubt Australian aborigines and others saw these objects long before written records were made.

AJames

20-09-2007, 12:46 PM

"RE: Halley's Gigantic Globular = omega Cen
I don't think we should credit Ptolemy with seeing omega Cen as a DSO.

Omega Centauri had been listed in Ptolemy's catalogue as a star. Halley was the first to document its non-stellar nature, and listed it as "luminous spot or patch in Centaurus" in his historical list of six such objects."

You do bring up an interesting debate, and one that has more shades of grey than the Moon!

However, I would like to put my spin on it....

Much of the debates about astronomy regarding the actual discoverer of the deep-sky objects are based on lists produced by noted astronomers. From the 15th Century, many of the "DSO's" or deep sky objects - suddenly appeared in the star Catalogues. Halley was just one of these, who produces a short list of six objects that we now recognise as anagalactic objects. In his original dissertation he speculated that these objects were to "occupy Spaces immensely great" which he goes on to say "Medium is diffused, shine with there own lustre." This appears in his Phil.Trans., 347, 390 (1715).

This was contrary to general belief of the day in the in the so-called Empyrean - the area of sky reserved for the angels and the gods - essentially the vault in the heavens. With the invention of the telescope, many more stars and seemingly hazy or nebulous objects were revealed, which were assumed to be holes in the firmament. Halley is the one to allegedly brake that assumption - an argument that was a noncontradiction - forming the (meaning metaphysical and physical) cosmological concept of the metagalaxy - but that is yet another debate - but to the crunch...

Due to this some now assert that this makes Halley the one to define the first DSO's. :D

All well and good. However, there are contrary views. The problem with astronomy between the mid- to late-17th through to the 20th Centuries was the rise of so-called "nationalistic astronomy", where whole nations vied for recognition of astronomical observers and institutions. Here the European nations of England, France, Germany (and it sub-forms) and to a lesser extent, the Russians. Perhaps the most popular example was Mr William Herschel - "Will" to his mates - who proclaimed the planet Uranus as "Georgium Sidus" after his generous (and likely psychiatric disabled) patron, England's King George III.

Here the great astronomers and scientists of the day vied for supremacy in the "Best Country Stakes" - the prize being the honour for the glory of the State. This ranged from star catalogues, star charts, constellation, planets, comets, etc. Here were the dirty tricks, true and false claims and counter claims, and manipulations of the truth became the order of the day, often backed up by expeditions with heady ambitions or financial support. The nuances between the English and the French were particularly fanatical, backed up by new science institutions and observers. Later these ambitions were somewhat quelled, but continue to simmer in the present day. Without going into detail, for brevity, the promotion of Halley has been especially relevant to the English, as was Lacaille for the French. (Another was the French Descartes v. Newton or even Neptune's Adams v. Le Verrier.)
[A 18th Century drinking ditty is an example of this contempt. See "The Astronomer's Drinking Song";
Ie. http://homepage.ntlworld.com/heather.hobden1/astronomy18c.htm

"Great Newton, who was never beat
Whatever fools may, think, sir;
Though sometimes he forgot to eat,
He never forgot to drink, sir:
Descartes took nought but lemonade,
To conquer him was play, sir;
Thefirst advance that Newton made
Was to drink his bottle a day, sir!"]

For the modern example, and likely the source of the DSO English favouritism was the English writer and once BAA Historical guru, Kenneth Glyn Jones is a classic example of this phenomena. This appears in his detailed book "The Search for Nebula" (1975). Each astronomer or observer is listed individually. Here Halley (pg.2) relation to omega centauri is described in detail, while oddly, Ptolemy (pg.7-8) is given the bums-rush - missing his observation all together! However, under Halley pg.24, he makes the claim that Ptolemy is often misquoted; see the translations below. This has proven to be false.

But even Halley has placed omega Cen in star catalogue (Object 180) in his "Catalogue of Southern Stars" (1677).

So, note the dates here. Omega Cen appear in a catalogue in 1677, but the claim of the deep-sky objects appears in 1715 - forty-eight (48) years later while Halley was starting musing about his life! (He died in 1742!)

Case in point... and here is the perpetuation of the myth.... while Halley observed Omega Cen the connection to it being a deep-sky object is a little stretch of the imagination.

The Case for Ptolemy

Observationally it could be argued that DSO's didn't really exist until even after Messier. Many of the globulars, due to the poor quality they were unresolved. For Ptolemy, I favour him because he was first to write down that the star was not stellar. (Halley also didn't realise Omega Centauri was stellar either!) For the wider discussion, this is what Ptolemy can be attributed too.

As I previously said;
"It was actually Ptolemy who discovered that the area was the "nebula on the back of the horse" - dorso Equino Nebulous."
[A translation of "(misty) nebula in tergus of equus" is sometimes quoted]

[The same text written by Jones (1975) says this quote is "Halley's and not Ptolemy's"; which has since been proven as false! Nationalism yet once again!]

This is also noted in the Almagest text (at least of the handed down copies available.)

Star 955 #21 of Centaurus; (Note : Ptolemy never knew it as "omega", (which was added later by cartographers in 15th Century) Thirty-seven stars were placed in Centaurus.

The position of No. 955 is described as; Quae est in principio scapulae or "Which is upon beginning sword belt"

I think Ptolemy deserves some credit!

Andrew