What Galaxy designation are these galaxies?

[swag72]

I am a little confused and have spent hours on the net trying to cross reference all sorts to try to get the answer..... I hope someone can help.

I have taken the following image and annotated it using the Hyperleda catalogue as well as the PGC catalogue. As you can see the PGC catalogue shows the larger galaxies (as did the Hyperleda catalogue). The Hyperleda also shows loads more galaxies with nothing more than a numerical designation. I have tried to find these in the Simbad database, but they don't show up at all. I've also looked at Aladin and some of these have an SDSS designation that has no bearing on the numbers that have come from the annotated image. 

Can anyone throw some light on this please? How can I find these on Simbad for example when it doesn't give me anything for the numbers alone.

[wimvb]

SDSS J150958.95+094939.2 -- Quasar??

For the one labeled 4450482 near the top.

I did a simbad coordinate search. In fact, I think that most of these are qso's

Edited May 9, 2020 by wimvb

[swag72]

10 minutes ago, wimvb said:

SDSS J150958.95+094939.2 -- Quasar??

For the one labeled 4450482 near the top.

I did a simbad coordinate search. In fact, I think that most of these are qso's

Quasars? Really? I thought that they were tiny things that you could hardly see?

[wimvb]

3 minutes ago, swag72 said:

Quasars? Really? I thought that they were tiny things that you could hardly see?

Quasars are tiny things that you can hardly see. Until you go looking for them. 😉

Btw

2MASX J15110350+1003419 for nr 3841448 near the bottom. A galaxy with redshift 0.03376. "Only" 444 Mly distant.

[swag72]

In this image then all of the blue PGC designations are galaxies...... No problem, get that! But the yellow ones are all quasars? 

[Kinch]

If they are Galaxies....they are bound to be in one of these catalogs...

https://heasarc.gsfc.nasa.gov/docs/cgro/db-perl/W3Browse/w3table.pl?MissionHelp=galaxy_catalog

 

They won't all be in Simbad....but some might. If you can access the actual list that those numbers appear in (good luck with the search through the catalogs).....sometimes those lists give other reference numbers. I remember doing this with a single star one (cross referencing between catalogs) and it was a real pain.

Edited May 9, 2020 by Kinch
update

[Star101]

I was doing so well counting those very very distant galaxies, 4568631, 4568632 erm, when I lost my number...start again...1, 2, 3......... 😄

Edited May 9, 2020 by Star101

[swag72]

8 minutes ago, Kinch said:

If they are Galaxies....they are bound to be in one of these catalogs...

https://heasarc.gsfc.nasa.gov/docs/cgro/db-perl/W3Browse/w3table.pl?MissionHelp=galaxy_catalog

OMG 🤯 I don't even know where to start looking in those!! That's a cracking resource though Brendan..... Thanks 👍

 

[Kinch]

I just updated my previous reply.......bottom line.....you may not be able to allocate a Simbad reference to that number in another catalog......but have fun searching.

Edited May 9, 2020 by Kinch

[Martin Meredith]

Hi Sara

Some of the yellow ones are galaxies too. Take a look at this chart and you'll see quite a few marked. Perhaps the yellow are the fainter galaxies?

cheers

Martin

BOO3989.pdf

[wimvb]

3 hours ago, swag72 said:

In this image then all of the blue PGC designations are galaxies...... No problem, get that! But the yellow ones are all quasars? 

The yellow ones are a mixture of quasars, "active galaxy nuclei", and plain galaxies. Some probably a few Gly distant.

[swag72]

6 minutes ago, wimvb said:

The yellow ones are a mixture of quasars, "active galaxy nuclei", and plain galaxies. Some probably a few Gly distant.

Ooooo..... how exciting. How would I know what were what? I tried a couple of the quasar catalogues that Brendan linked to but nothing came up...... Any ideas? I wouldn't even have considered quasars.... I need to go and do some reading about what they even are LOL!!!!  

[Knight of Clear Skies]

4 hours ago, swag72 said:

Quasars? Really? I thought that they were tiny things that you could hardly see?

They are point sources (well, apart from a few gravitationally lensed ones) but it's really surprising how many can be captured with amateur equipment, and at what ridiculous distances. Pretty Deep Maps is a good reference for Quasar hunting, authored by forum member Martin Meredith. I did find a link to a quasar challenge page but unfortunately it seems to have gone dead.

I'm pretty sure I captured a mag 18.5 quasar in the background of this image, with a DSLR and camera lens. It's 11.6 billion light years away (lookback time, so the photons have been travelling for most of the history of the universe). But it's just a faint dot, I'd never have identified it if it wasn't in existing catalogues. A good-sized telescope should be able to take a spectrum of one and measure its redshift.

Edited May 9, 2020 by Knight of Clear Skies

[wimvb]

I use Simbad and search either by id or by coordinates. To find pgc galaxies, I replace 'pgc' by 'leda'. 

http://simbad.u-strasbg.fr/simbad/sim-fid

Once I find something, I use the Aladin light link for a visual search. In Aladin I activate simbad.

[ollypenrice]

14 minutes ago, swag72 said:

Ooooo..... how exciting. How would I know what were what? I tried a couple of the quasar catalogues that Brendan linked to but nothing came up...... Any ideas? I wouldn't even have considered quasars.... I need to go and do some reading about what they even are LOL!!!!  

I have a book bought second hand which has an excellent section on Quasars. If I could remember which book it is this would be a much more itneresting post! Give me a day or two...

😁lly

[wimvb]

1 minute ago, ollypenrice said:

I have a book bought second hand which has an excellent section on Quasars. If I could remember which book it is this would be a much more itneresting post! Give me a day or two...

😁lly

Cliffhanger. 😋

[Knight of Clear Skies]

Good article here about finding quasars, there are a few above mag 14 which are suitable for visual observation.

[wimvb]

This past galaxy season I tried to go deep. We moved to a darker location last year, and I built an obsy. So despite the bad weather, I was able to do more imaging than before, resulting in a few images like this. 

Members of a Swedish astroforum helped me identify some of the "faint fuzzies". They also directed me to simbad. Just passing it forward. 

Edited May 9, 2020 by wimvb

[Datalord]

6 hours ago, swag72 said:

I need to go and do some reading about what they even are LOL!!!!

Wait until you start wondering how far away they are and how you figure that out. Once you start messing with Z value over 1, you brain starts hurting. Supposedly I managed to capture a Z=3.1 quasar in an image, which depending on how you define the constant for the expansion of the universe, will mean it is something like 42 billion light years away today.

That said, it would be really nice to have a single catalog for these quasars we could just plot into an annotation.

[swag72]

9 hours ago, wimvb said:

I use Simbad and search either by id or by coordinates. To find pgc galaxies, I replace 'pgc' by 'leda'. 

http://simbad.u-strasbg.fr/simbad/sim-fid

Once I find something, I use the Aladin light link for a visual search. In Aladin I activate simbad.

I've used Simbad and Aladin on this.... it's quite a manual way of doing it, I was rather hoping that there was a quasar catalogue then that I could download into PI to annotate if there's anything there.

[swag72]

My next dilemma then is the following..... Using Aladin I have come up with so many pages where I really don't know what I'm looking at. For example this link - What is the 'thing' I am looking at on this linked page? I can't see anywhere a simple 'this is a galaxy' or something else.......

I think I'm a bit simple minded to be able to sort all of this out! Scientifically the words, figures etc just mean nothing to me whatsoever.....

[Knight of Clear Skies]

31 minutes ago, swag72 said:

My next dilemma then is the following..... Using Aladin I have come up with so many pages where I really don't know what I'm looking at. For example this link - What is the 'thing' I am looking at on this linked page? I can't see anywhere a simple 'this is a galaxy' or something else.......

I think I'm a bit simple minded to be able to sort all of this out! Scientifically the words, figures etc just mean nothing to me whatsoever.....

Yes, it's not the most readable page, I think you're looking at raw photometry data and calibration parameters. There appear to be coordinates and various magnitudes (different wavelengths, but I can't see the key). Simbad might be a bit more useful to you as it has an object type designation (often with a ? next to objects when their nature isn't confirmed).

I've used Simbad a bit but it's not easy to get it to do what I want (e.g. search for a type of object around a given coordinate to identify, say, satellite galaxies or quasars). If anyone knows of a guide to using it I'd be grateful. (Failing that, a do know a professional astronomer I could ask.)

[wimvb]

Yes, that page is a summary page of astrometry and photometry data on this object (a galaxy). No need to go this far, imo.

The basic object page (click on the Simbad icon in the link you provided, then on the identifier in the first row of the table), has all the data you could possibly need, and then some.

http://simbad.u-strasbg.fr/simbad/sim-id?Ident=%4010533343&Name=2MASX J15110350%2b1003419&submit=submit

This page has coordinates (in several systems/units), distance data (redshift, z), and magnitude data (fluxes). Further down it will list children (eg single galaxies of a group, or supernovae in a galaxy, etc), siblings, and parents (eg group to which a galaxy belongs). I rarely dive deeper into the data than that. If you do, Simbad, Vizier and Aladin have documentation explaining features.

http://simbad.u-strasbg.fr/simbad/

[swag72]

Maybe one last query then if I may......... Thank you for all our help so far, it's been invaluable 🙂

In this link where I have had to go to the CDS portal as nothing showed in Simbad........ The Aladin screen shows the item of interest in the crosshair, but how do I know what THAT actually is? 

• 2MASX J15100535+0943230 (Galaxy)
• 2MASX J15104417+0942270 (Galaxy)
• 2MASX J15100704+0957160 (Seyfert 2 Galaxy)
• SDSS J151025.65+100414.2 (Quasar)
• 2MASX J15105281+0955349 (LINER-type Active Galaxy Nucleus)
• SDSS J151012.48+095722.4 (Brightest galaxy in a Cluster (BCG))
• SDSS J150958.95+094939.2 (Quasar)

[Knight of Clear Skies]

2 hours ago, wimvb said:

http://simbad.u-strasbg.fr/simbad/sim-id?Ident=%4010533343&Name=2MASX J15110350%2b1003419&submit=submit

The redshift parameter (z(spectroscopic) 0.03376) can be converted into a distance estimate, using online calculators.