What Globular Cluster is this?

alphajuno (Dave) · #1 28-07-2008, 03:43 AM

Please don't spend a lot of time on this but if you recognize this GC, please let me know. I misidentified the file and spent a couple of hours yesterday trying to figure out what it is. I took it at 4 a.m. on 7/3/08 in west Texas (near El Paso). It's probably near Capricorn because I was in that part of the sky at the time. Also, the image capture times were only around 4 seconds and the FOV is around 20'. It's oriented as my SCT sees it. Thanks! It's driving me crazy!

ngcles · #2 28-07-2008, 05:55 PM

Hi Alphajuno & All,

Well the clue that it is near Capricornus is pretty vital and I'm almost certain it is M30. I've taken a look at the DSS overlay on Megastar with N up and a mirror reversed image so that N is up and E is to the right and the bright star on the edge of the cluster to the left of the frame fits well to being:

T 6940:939:1 PPM 272790 SAO 190531 HD 206034
RA: 21h 39m 57.000s Dec: -23° 11' 56.70"
Mag(v): 8.63 B-V: +0.164 Spect: A3V

Some other patterns on that side of cluster in your image and the DSS fit _reasonably_ well, so I'd say it is very likely to be M30. I've also looked at M2 M15, M71, M75 and M72 as possibles but ruled them out. There are few (read: none I believe) other bright GCs in the area that could fit the bill and have that bright star on the edge.

So M30 it is.

Best,

Les D

alphajuno (Dave) · #3 29-07-2008, 08:03 AM

OK great, thanks! I should have done these pics while it was fresh in my mind!

GrahamL · #4 29-07-2008, 08:29 PM

looks like M2 a bit ? . when you invert that tight little grouping at
9 o'clock http://images.google.com.au/imgres?imgurl=http://hou.lbl.gov/~vhoette/Explorations/MessierGallery/alljpegs/mgm002.jpg&imgrefurl=http://hou.lbl.gov/~vhoette/Explorations/MessierGallery/m2.html&h=505&w=505&sz=45&hl=en&sta rt=11&um=1&tbnid=c1LcH43ma3ZI3M:&tb nh=130&tbnw=130&prev=/images%3Fq%3Dngc%2B7089%26um%3D1%26 hl%3Den%26sa%3DG

ngcles · #5 30-07-2008, 03:25 PM

Hi Alphajuno, Nightstalker & All,

Hey Nightstalker, I reckon you're right!

I took the image you posted and flipped it top to bottom in Photoshop, and it fits the image supplied by Alphajourno _absolutely perfectly_. I've attached the flipped nightstalker image for all to compare to Alphajourn's image. I'd incorrectly discounted M2 earlier on the basis of the DSS image which is well overexposed.

M2 it is -- no doubt this time I'd say. Well spotted mate!

Best,

Les D