Strange= galaxy PGC3097159

Lester · #1 13-04-2012, 09:56 AM

Hi all, last night I tried for comet Metcalf/Brewington and missed the FOV with the Astrograph. Thought I would still process the stack of exposures to see what I had. Well at the exact postion of galaxy PGC3097159 there is this red object. That galaxy is listed in The Sky6 pro at magnitude 30 and size=0". So way too faint and small to show up here. I thought is may be a nebula, but nothing in my program.

I am sure it is not camera noise as such a large red area hasn't shown up before with the Astro 40D.

Any sensible thoughts welcome.

astroron (Ron) · #2 13-04-2012, 10:49 AM

Quote:

Originally Posted by Lester

Hi all, last night I tried for comet Metcalf/Brewington and missed the FOV with the Astrograph. Thought I would still process the stack of exposures to see what I had. Well at the exact postion of galaxy PGC3097159 there is this red object. That galaxy is listed in The Sky6 pro at magnitude 30 and size=0". So way too faint and small to show up here. I thought is may be a nebula, but nothing in my program.

I am sure it is not camera noise as such a large red area hasn't shown up before with the Astro 40D.

Any sensible thoughts welcome.

Lester, you could try NED or SEDS to get the true mag of the galaxy
PGC3097159.
Even the largest of telescopes have trouble getting down to mag 30, so I think "THE SKY" Six is in error.
I think you should not have too much trouble getting down to mag 20 or so in your scope with long exposures.
Cheers

Lester · #3 13-04-2012, 11:00 AM

Thanks Ron for your reply, I will look into it a bit further. Although I am sure what ever I got has nothing to do with such a distant faint galaxy, just that it is in the same position.

All the best.

thunderchildobs · #4 13-04-2012, 12:20 PM

In TheSky Mag 30 and size = 0 general indicates that details of the object are not known.

Brendan

TrevorW · #5 13-04-2012, 01:41 PM

Smudge

Lester · #6 13-04-2012, 01:55 PM

Rob K. To the rescue again. Found unlisted nebula on D.S plate.

TrevorW · #7 13-04-2012, 02:16 PM

Thought as much but didn't won't to say and make myself sound stupid the colour just didn't look right for a galaxy

rogerg (Roger) · #8 13-04-2012, 02:53 PM

Interesting object.

Agree with Brendan, mag 30 in TheSky means the TheSky database doesn't know the magnitude, and makes me question it's other information about such an object.

Do a query for "galaxies" brighter than mag 15 from TheSky, photograph each one, and it's amazing what objects will turn up. Globular Clusters are surprisingly common as well as open clusters, you'd think they would be properly cataloged at least.

PeterM · #9 13-04-2012, 04:21 PM

Hi Lester,

If you don't already have it this site is very useful. A search by name of object or co-ordinates will give you a DSS image of the area.
http://archive.stsci.edu/cgi-bin/dss_form

The NED site that Ron refers to is listed below below and can be searched by a host of criteria.
http://ned.ipac.caltech.edu/

Yup Roger is right, it wasn't that long ago that NGC5189 in Musca was classed as a galaxy and is now classed as a planetary nebula - The Spiral Planetary in Musca

Did you end up finding a Sky6 Pro?
PeterM.

Lester · #10 13-04-2012, 04:44 PM

Thanks for your comments everyone, I appreciate them.

Yes Peter I got a copy of The Sky6 Pro from chap on IIS and also got your extra stars loaded into it. Works well. Thanks for those links I will save them for future reference.

All the best.