Tentacles of the Tarantula Nebula (APOD 22 Aug 2007)

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bystander
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Tentacles of the Tarantula Nebula (APOD 22 Aug 2007)

Post by bystander » Wed Aug 22, 2007 3:19 pm

http://antwrp.gsfc.nasa.gov/apod/ap070822.html

I assume the stars with diffration spikes are in our own galaxy, but are all the other stars in the LMC? And the cluster on the left edge center (9:30), is that in the LMC? There seem to be a lot of small star clusters in this picture, were they all formed within the Tarantula Nebula?

Beautiful picture. My compliments to ESO.
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Re: Tentacles of the Tarantula Nebula ap070822

Post by Andy Wade » Wed Aug 22, 2007 5:15 pm

bystander wrote:http://antwrp.gsfc.nasa.gov/apod/ap070822.html

I assume the stars with diffration spikes are in our own galaxy, but are all the other stars in the LMC? And the cluster on the left edge center (9:30), is that in the LMC? There seem to be a lot of small star clusters in this picture, were they all formed within the Tarantula Nebula?

Beautiful picture. My compliments to ESO.
Yes indeed. It is a beautiful picture.

ISTR reading that all stars that can be resolved as individual points are in our own Milky Way galaxy.
Regards,
Andy.

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Post by BMAONE23 » Wed Aug 22, 2007 5:42 pm

I would like to see what that Purple shaded area in the upper right corner looks like.

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Re: Tentacles of the Tarantula Nebula ap070822

Post by iamlucky13 » Wed Aug 22, 2007 7:37 pm

Andy Wade wrote:
bystander wrote:http://antwrp.gsfc.nasa.gov/apod/ap070822.html

I assume the stars with diffration spikes are in our own galaxy, but are all the other stars in the LMC? And the cluster on the left edge center (9:30), is that in the LMC? There seem to be a lot of small star clusters in this picture, were they all formed within the Tarantula Nebula?

Beautiful picture. My compliments to ESO.
Yes indeed. It is a beautiful picture.

ISTR reading that all stars that can be resolved as individual points are in our own Milky Way galaxy.
In most images that would be true, however, I think this is an exception. The LMC is much closer than any other galaxy, so the resolution is higher.

The star density seems too great unless perhaps the LMC happens to be in the same plane as the Milky Way (I'm pretty sure it's not, though), in which case we could be looking through one of our galaxies arms at it. Even then, the angle distance between stars seems small for nearby stars. We're looking at an area only about 1/2 degree across.

Also, the star density is very uniform across the image, but if you look at the green-ish portion of the nebula in the full-size image, you can see that the apparent density is much lower, suggesting that some of those stars are in front of the nebula and some are behind and obscured by it.

So I think bystander is right. The stars with diffraction spikes are in our own galaxy and the rest are in the LMC.

It's worth checking out an overall picture of the LMC for perspective:
http://antwrp.gsfc.nasa.gov/apod/ap040902.html
"Any man whose errors take ten years to correct is quite a man." ~J. Robert Oppenheimer (speaking about Albert Einstein)

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Post by bystander » Wed Aug 22, 2007 8:09 pm

I'm still curious about the cluster @ 9:30 in the picture. In none of the pictures I've found of the LMC and 30 Doradus do I find a cluster that close to the Tarantula Nebula in our own galaxy. I'm thinking that must be R136. If so, I'm very impressed with the resolution. This must be an extreme closeup.
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Re: Tentacles of the Tarantula Nebula ap070822

Post by Case » Thu Aug 23, 2007 1:23 am

iamlucky13 wrote:The star density seems too great unless perhaps the LMC happens to be in the same plane as the Milky Way (I'm pretty sure it's not, though).
True, the Magellanic Clouds are at positions quite separate from the Milky Way.

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Post by DavidLeodis » Thu Aug 23, 2007 6:42 pm

It's a great image, but I'm unsure which is R136. This is a good example of where an annotated version would be helpful.

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Post by BMAONE23 » Thu Aug 23, 2007 7:34 pm

GOOGLE SKY brings the entire nebula area into view as R136

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Post by bystander » Thu Aug 23, 2007 9:09 pm

R136 is supposed to be the star cluster at the center of 30 Doradus (Tarantula Nebula) as in: http://antwrp.gsfc.nasa.gov/apod/ap010730.html. But I was wondering if it is the star cluster shown at the left edge of http://antwrp.gsfc.nasa.gov/apod/ap070822.html
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Post by BMAONE23 » Thu Aug 23, 2007 9:24 pm

the top link image looks like it sits in the center of the bright yellow region in the bottom linked image only rotated about 30deg or so CCW.

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Post by DavidLeodis » Fri Aug 24, 2007 5:14 pm

I'm still unsure which is R136. However, a little to the left of center there is a bright star with image spikes (presumably a foreground star) and immediately to its left is what looks like a small cluster of bright stars. On using the zoom facility that group then looks much more impressive and so I wonder if that is R136 based on the explanation to the APOD that it is "The bright knot of stars left of center". :? but still :) ing!

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Re: Tentacles of the Tarantula Nebula ap070822

Post by NoelC » Tue Aug 28, 2007 10:41 pm

Andy Wade wrote: ISTR reading that all stars that can be resolved as individual points are in our own Milky Way galaxy.
Actually the Hubble is quite capable of resolving individual stars in other galaxies far more distant than the Magellanic clouds.

It's not a safe bet that the diffraction spikes differentiate Milky Way stars from those in the more distant Magellanic cloud... It's really only safe to say the stars with spikes are much brighter than those without.

-Noel

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