|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Andromeda three times bigger than previously thought
|
#2
|
|||
|
|||
On Tue, 31 May 2005 15:00:29 +0200
Charles D. Bohne wrote: On Tue, 31 May 2005 10:37:24 +0100, Ray Vingnutte wrote: =20 Well there you go....now you know http://pr.caltech.edu/media/Press_Releases/PR12703.html =20 Thanks, Ray!! C. =20 =B0 Scott Chapman, from the California Institute of Technology, and Rodrigo Ibata, from the Observatoire Astronomique de Strasbourg in France, have led a team of astronomers in a project to map out the detailed motions of stars in the outskirts of the Andromeda galaxy. Their recent observations with the Keck telescopes show that the tenuous sprinkle of stars extending outward from the galaxy are actually part of the main disk itself. This means that the spiral disk of stars in Andromeda is three times larger in diameter than previously estimated. Thats just the sort of info Darla could have given us without any fear of us using it as a weapon, if she had then we would now all be going WOOOOAAAAA it's all true..... =20 |
#3
|
|||
|
|||
Hi Ray That begs the question can we relate this with our Milky Way?
Should we now say Andromeda is 4 times bigger than the Milky way. I wonder if it could be a little closer too bert |
#4
|
|||
|
|||
In message , Ray Vingnutte
writes Well there you go....now you know http://pr.caltech.edu/media/Press_Releases/PR12703.html Thanks Ray. The paper at http://xxx.lanl.gov/abs/astro-ph/0504164 says it's about 4 degrees across in the sky, eight times the apparent diameter of the Moon. -- Remove spam and invalid from address to reply. |
#5
|
|||
|
|||
On Tue, 31 May 2005 18:58:19 +0100
Jonathan Silverlight wrote: In message , Ray Vingnutte writes Well there you go....now you know http://pr.caltech.edu/media/Press_Releases/PR12703.html Thanks Ray. The paper at http://xxx.lanl.gov/abs/astro-ph/0504164 says it's about 4 degrees across in the sky, eight times the apparent diameter of the Moon. Thanks, can I ask how you find those papers, from the link I gave I can't see how you get from that to the paper on the site you posted. -- Remove spam and invalid from address to reply. |
#6
|
|||
|
|||
In message , Ray Vingnutte
writes On Tue, 31 May 2005 18:58:19 +0100 Jonathan Silverlight wrote: In message , Ray Vingnutte writes Well there you go....now you know http://pr.caltech.edu/media/Press_Releases/PR12703.html Thanks Ray. The paper at http://xxx.lanl.gov/abs/astro-ph/0504164 says it's about 4 degrees across in the sky, eight times the apparent diameter of the Moon. Thanks, can I ask how you find those papers, from the link I gave I can't see how you get from that to the paper on the site you posted. Remarkably quickly. I was expecting to have to do a search because it looked interesting, but the press release has a link to Scott Chapman's home page at http://www.astro.caltech.edu/~schapman/m31.html and that has a link to "Want Details?" at http://www.astro.caltech.edu/%7Eschapman/halo.html. From there to "THE BONUS: MEASURING THE HALO" at http://www.astro.caltech.edu/%7Eschapman/halo.html and then to Ibata et al. 2005 under "THE DISK". I've just noticed that the link to Chapman's own paper at http://xxx.lanl.gov/abs/astro-ph/0506232 doesn't work! |
#7
|
|||
|
|||
On Wed, 1 Jun 2005 18:51:07 +0100
Jonathan Silverlight wrote: In message , Ray Vingnutte writes On Tue, 31 May 2005 18:58:19 +0100 Jonathan Silverlight wrote: In message , Ray Vingnutte writes Well there you go....now you know http://pr.caltech.edu/media/Press_Releases/PR12703.html Thanks Ray. The paper at http://xxx.lanl.gov/abs/astro-ph/0504164 says it's about 4 degrees across in the sky, eight times the apparent diameter of the Moon. Thanks, can I ask how you find those papers, from the link I gave I can't see how you get from that to the paper on the site you posted. Remarkably quickly. I was expecting to have to do a search because it looked interesting, but the press release has a link to Scott Chapman's home page at http://www.astro.caltech.edu/~schapman/m31.html and that has a link to "Want Details?" at http://www.astro.caltech.edu/%7Eschapman/halo.html. From there to "THE BONUS: MEASURING THE HALO" at http://www.astro.caltech.edu/%7Eschapman/halo.html and then to Ibata et al. 2005 under "THE DISK". I've just noticed that the link to Chapman's own paper at http://xxx.lanl.gov/abs/astro-ph/0506232 doesn't work! Thanks again, I'll keep eyes open next time. Just saw on the news, missed most of it, about a five year long simulation of the universe, can;t find any more about it yet, no doubt a link will turn up in a while;-) |
#8
|
|||
|
|||
"Ray Vingnutte" wrote...
in message ... Well there you go....now you know http://pr.caltech.edu/media/Press_Releases/PR12703.html 'Lo Ray -- I just caught this... and i don't get it. This says that it was previously thought that Andromeda was only 70,000 to 80,000 ly in diameter, or somewhat smaller in size than our Milky Way which "weighs in" at about 100,000 ly across. And that now we believe that Andromeda is 220,000 ly across. When i was a kid i remember reading that Andromeda was believed to be 2 or 3 times as big as the Milky Way. And this was confirmed for me many years ago by the SEDS website... "Under "normal" viewing conditions, the apparent size of the visible Andromeda Galaxy is about 3 x 1 degrees (our acurate value, given above, is 178x63 arc minutes, while NED gives 190x60'). Careful estimates of its angular diameter, performed with 2-inch binoculars, by the French astronomer Robert Jonckhere in 1952-1953, revealed an extension of 5.2 times 1.1 degrees (reported by Mallas), corresponding to a disk diameter of over 250,000 light years at its distance of 2.9 million light years, so that this galaxy is more than double as large as our own Milky Way galaxy !" Ref.: http://www.seds.org/messier/m/m031.html So why do these people think that Andromeda is larger than we've believed it to be ever since we found out that it's a galaxy? The funny thing is, when i looked at the title of this thread, i went, "WOW, Andromeda is about 750,000 light years across???" We already *knew* Andromeda was about 220,000 ly in diameter (which is actually 30,000 ly LESS than the old SEDS figure). So what's the big fuss??? happy days and... starry starry nights! -- Space so scary, quite contrary, How does your nothing grow? A just as hairy corollary... What makes your nothing flow? Indelibly yours, Paine http://www.savethechildren.org/ |
#9
|
|||
|
|||
On Wed, 15 Jun 2005 15:40:42 GMT
"Painius" wrote: "Ray Vingnutte" wrote... in message ... Well there you go....now you know http://pr.caltech.edu/media/Press_Releases/PR12703.html 'Lo Ray -- I just caught this... and i don't get it. This says that it was previously thought that Andromeda was only 70,000 to 80,000 ly in diameter, or somewhat smaller in size than our Milky Way which "weighs in" at about 100,000 ly across. And that now we believe that Andromeda is 220,000 ly across. Well I would expect anything and almost everything to change, even the size of our own galaxy maybe. When i was a kid i remember reading that Andromeda was believed to be 2 or 3 times as big as the Milky Way. And this was confirmed for me many years ago by the SEDS website... See above comment ;-) "Under "normal" viewing conditions, the apparent size of the visible Andromeda Galaxy is about 3 x 1 degrees (our acurate value, given above, is 178x63 arc minutes, while NED gives 190x60'). Careful estimates of its angular diameter, performed with 2-inch binoculars, by the French astronomer Robert Jonckhere in 1952-1953, revealed an extension of 5.2 times 1.1 degrees (reported by Mallas), corresponding to a disk diameter of over 250,000 light years at its distance of 2.9 million light years, so that this galaxy is more than double as large as our own Milky Way galaxy !" Sounds all perfectly normal really, a lot of this is likely all subject to change, there's no real firm consensus on the number of stars in our own galaxy, figures vary and vary with all measurements I think. So it would come as no surprise to find different values for all sorts of things, it's just normal it seems. Ref.: http://www.seds.org/messier/m/m031.html So why do these people think that Andromeda is larger than we've believed it to be ever since we found out that it's a galaxy? According to the article about 3,000 stars that were not considered part of the main disk are now considered as such The funny thing is, when i looked at the title of this thread, i went, "WOW, Andromeda is about 750,000 light years across???" We already *knew* Andromeda was about 220,000 ly in diameter (which is actually 30,000 ly LESS than the old SEDS figure). So what's the big fuss??? Hmm, see what you mean, tricky, and interesting, I have no idea ;-) but would like to know. happy days and... starry starry nights! -- Space so scary, quite contrary, How does your nothing grow? A just as hairy corollary... What makes your nothing flow? Indelibly yours, Paine http://www.savethechildren.org/ |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Could galactic find be Andromeda's food? (Forwarded) | Andrew Yee | Astronomy Misc | 0 | January 9th 04 06:58 PM |
UFO Activities from Biblical Times | Kazmer Ujvarosy | Astronomy Misc | 0 | December 25th 03 05:21 AM |
Case, WIYN astronomers discover new galaxy orbiting Andromeda (Forwarded) | Andrew Yee | Astronomy Misc | 0 | November 7th 03 04:27 PM |
Incontrovertible Evidence | Cash | Astronomy Misc | 1 | August 24th 03 07:22 PM |
Incontrovertible Evidence | Cash | Amateur Astronomy | 6 | August 24th 03 07:22 PM |