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link gurus? star and galaxy lists

Posted: Fri Dec 22, 2006 4:26 pm
by ckam
I've seen some at wikipedia, but those are quite useless.
I need list of brightest stars and galaxies, with polar coordinates, brightness and color (ideally RGB :). aNyone?

Re: link gurus? star and galaxy lists

Posted: Fri Dec 22, 2006 4:58 pm
by Nereid
ckam wrote:I've seen some at wikipedia, but those are quite useless.
I need list of brightest stars and galaxies, with polar coordinates, brightness and color (ideally RGB :). aNyone?
"Brightest" how? Apparent (visual) magnitude (integrated, in the case of galaxies)? And how many? top 100? 10,000?

For stars, perhaps the best list would be the HIPPARCOS catalogue; for galaxies, the RC3 catalog (I'm not sure how the latter treats some of the galaxies 'hidden' in the Milky Way plane, esp SagDEG).

Posted: Fri Dec 22, 2006 9:59 pm
by harry
Hello All

Thank you Nereid for those links.

Just reading through them, it takes close to a billion years for one of the dwarf galaxies to go round our milky way.

For the milky way to evolve with our neighbours I do not think 13.7 Gys is enough time.

Posted: Fri Dec 22, 2006 10:17 pm
by Nereid
harry wrote:Hello All

Thank you Nereid for those links.

Just reading through them, it takes close to a billion years for one of the dwarf galaxies to go round our milky way.

For the milky way to evolve with our neighbours I do not think 13.7 Gys is enough time.
Just one 'close encounter of the Milky Way kind' is more than enough to wreck havoc on a galaxy like SagDEG.

SDSS has some nice results re streams (google on SDSS and 'field of streams'), as well as some earlier results on tidal stripping of globular clusters ... these are all 'just what Newton ordered', in terms of matching theory with observation (though I think it was the Toomre brothers, in the 1970s, who did the first numerical simulations which showed how - in detail - tidal tails would be created in galaxy collisions).

So, other than your own, anti-scientific, biases, what is your opinion based on?

Posted: Fri Dec 22, 2006 10:21 pm
by harry
Hello Nereid

Which opinion are you directing to ?

Posted: Fri Dec 22, 2006 10:39 pm
by Nereid
harry wrote:Hello Nereid

Which opinion are you directing to ?
This one:
harry wrote:For the milky way to evolve with our neighbours I do not think 13.7 Gys is enough time.

Posted: Fri Dec 22, 2006 10:49 pm
by harry
Hello Nereid

Research into this would be great.

If some has done a calculation, I'm interested.

But! not by people who are directed to think along some lines.

Posted: Fri Dec 22, 2006 11:36 pm
by Nereid
harry wrote:Hello Nereid

Research into this would be great.

If some has done a calculation, I'm interested.

But! not by people who are directed to think along some lines.
Cool.

So when you wrote "I do not think", your thinking was based on ... what, precisely?

Your own guesses? Or your own research into the gravitational interactions between dwarf galaxies and (large) spirals?

Of course I could point you to some papers ... but it seems that you have already decided, even before you read any of them, that you will reject them ("But! not by people who are directed to think along some lines.")

And, as we all know, from reading your posts here, in the Cafe, your own approach to astronomy is, shall we say, idiosyncratic?

And, going further, we may conclude that whatever approach you seem to have chosen, towards understanding the modern sciences of physics, astronomy, astrophysics, and cosmology, it has merely a random correspondence with the principles of said sciences.

Or maybe not - have I misunderstood your basic approach?

Posted: Sat Dec 23, 2006 7:52 am
by harry
Hello Nereid

you said
And, going further, we may conclude that whatever approach you seem to have chosen, towards understanding the modern sciences of physics, astronomy, astrophysics, and cosmology, it has merely a random correspondence with the principles of said sciences
Mate, not I but you.

I read everything, so please do not judge people. If you have info for me to read. Not just for me, but for all who read this link.

Maybe I would question it or them, but others may agree.

Re: link gurus? star and galaxy lists

Posted: Mon Dec 25, 2006 8:14 am
by ckam
Perhaps you two should start Nereid-vs-harry thread with the poll attached so the rest could vote on who wins?
Nereid wrote:For stars, perhaps the best list would be the HIPPARCOS catalogue;
This would be great but it has no color information :( I am looking to make something like this, but with color, a bit more real-time, user-friendlier, etc (I'm sure you remember what for).

I will check other links later.

Posted: Mon Dec 25, 2006 8:21 am
by ckam
same with RC3 list:

Code: Select all

13.4  UGC 12889     # PGC    2 .SBT3..  5017 km/s
????? MCG -1- 1- 16 # PGC   12 .S..1P? 
????? MCG -1- 1- 20 # PGC   23 .E+..*. 
13.91 ESO   12- 12  # PGC   30 PSXT4P. 
????? UGC 12894     # PGC   35 .I..9..   329 km/s
14.6  UGC 12893     # PGC   38 .SA.8..  1108 km/s
15.40 UGC 12892     # PGC   39 .SB.2.. 
14.36 ESO  293- 27  # PGC   43 .SBR4*. 
????? UGC 12895     # PGC   53 .S..7..  6752 km/s
14.87 UGC 12897     # PGC   54 .S..2..  8705 km/s
  • "?????" (which you can see 4 times out of 10) is not really valid magnitude, is it?
  • no color either, unless it is somehow encoded in "designation".
:(

Any way, I will apreciate any further help on getting data in question.

Posted: Fri Dec 29, 2006 1:44 am
by Orca
ckam: if you don't have one, a sky chart for your PC can help...you can filter the Messier/NGC objects that are displayed on your screen by apparent magnitude.


EasySky has a free trial version to play with.

Posted: Mon Jan 15, 2007 9:47 am
by ckam
I am now making an app to convert celestia data. Since 1.3.x, they added all hipparcos catalog (whatever the spelling is) and some more. Good thing about celestia is that I can use its source to compute stars temperature (and in fact whatever I want).

Posted: Fri Jan 19, 2007 12:59 pm
by ckam
well, I'm like done with celestia, with first results coming somewhere next week.

I think I could use some help with math, namely, calculating sky map from star coordinates based on location on earth and time of the day. I will surely do this on my own, but it would be nice to make sure I've made no mistake.

Posted: Mon Jan 22, 2007 10:38 am
by ckam
....editing this post to let you know that i no longer need any math help 8)

Re: link gurus? star and galaxy lists

Posted: Thu Apr 24, 2008 2:36 am
by 0adomi
ckam wrote:I've seen some at wikipedia, but those are quite useless.
I need list of brightest stars and galaxies, with polar coordinates, brightness and color (ideally RGB :). aNyone?
Maybe the url below will be helpful for u

List of brightest stars

List of galaxies