Tadpoles Nebula with mysterious moving objects - please help!

[SilverAstro]

via SIMBAD perhaps ? , cat, range of pm (< = > ), search box or circle, etc.   but I havnt yet decided what to do about epoch, either specify it from Goran's  current frame ( syntactical man-traps !) or use the default J2000 and reduce Gorans co-ords ( mathematical man-traps !) I suspect a box big enough to do a catch-all might return too much ??

and my domestic staff have designs on the rest of my day   Good luck

ooops nearly forgot the link :  http://simbad.u-strasbg.fr/simbad/

 

[beka]

Hi again Gorann, Your objects have got into my head and I can't leave them alone :-) But this issue also generally raises the question of how we could identify and get information on faint objects such as these. Looking around I found that Cartes du Ciel supports the USNO-B1.0 catalog with over 1 billion stars to visual magnitude 21, and it seems to include information on proper motion. However it is 46GB and I don't think I will be able to download it - maybe your Internet connection will allow you. The same catalog has an search interface at http://www.usno.navy.mil/USNO/astrometry/optical-IR-prod/icas/fchpix. I will try these if Broadband Internet is cooperative. Otherwise let us know if  you if you get any further info.

Good Luck!

[beka]

1 hour ago, SilverAstro said:

via SIMBAD perhaps ? , cat, range of pm (< = > ), search box or circle, etc.   but I havnt yet decided what to do about epoch, either specify it from Goran's  current frame ( syntactical man-traps !) or use the default J2000 and reduce Gorans co-ords ( mathematical man-traps !) I suspect a box big enough to do a catch-all might return too much ??

and my domestic staff have designs on the rest of my day   Good luck

ooops nearly forgot the link :  http://simbad.u-strasbg.fr/simbad/

 

Hi SilverAstro, I tried the VisieR interface with just the object name IC 410 but I guess it was to  broad. If Gorann has the coordinates we should be able to find the objects by giving a suitable search radius in the VisieR interface. It brings up a picture with the objects of the search result marked.

[gorann]

2 minutes ago, beka said:

Hi SilverAstro, I tried the VisieR interface with just the object name IC 410 but I guess it was to  broad. If Gorann has the coordinates we should be able to find the objects by giving a suitable search radius in the VisieR interface. It brings up a picture with the objects of the search result marked.

Thanks for your efforts! I will try to get the coordinates and get back to you.

PS. I have a quite slow mobile broadband internet where I am now so Gb downloads are not possible.

[gorann]

16 minutes ago, beka said:

Hi SilverAstro, I tried the VisieR interface with just the object name IC 410 but I guess it was to  broad. If Gorann has the coordinates we should be able to find the objects by giving a suitable search radius in the VisieR interface. It brings up a picture with the objects of the search result marked.

Hi again

I got the cooridinates by a bit of trial and error in the DSS database for the POSS2 image. I ended up with RA: 05.21.44, Dec:+33.22.00.

Using those coordinates to retrieve  a 5 x 5 arcmin area from POSS2red in DSS gives this image with the mystic "double star" pretty much in the middle:

I hope you can use them to find out more

[gorann]

1 hour ago, beka said:

Hi SilverAstro, I tried the VisieR interface with just the object name IC 410 but I guess it was to  broad. If Gorann has the coordinates we should be able to find the objects by giving a suitable search radius in the VisieR interface. It brings up a picture with the objects of the search result marked.

Here is a crop from my RGB image. It suggests that the larger star is red and the smaller blue.

[beka]

3 minutes ago, gorann said:

Here is a crop from my RGB image. It suggests that the larger star is red and the smaller blue.

So Gorann, here is where I am so far. I have attached a screen capture of the VisieR search. I figure your star is XPM 246-0155519 second from the top in the list. The proper motions of 0.49 and 0.71 arcsecs/year for RA kind of match your estimate though I do not really get what these two numbers mean. (I think something to do with the accuracy of the values). 

[gorann]

3 minutes ago, beka said:

So Gorann, here is where I am so far. I have attached a screen capture of the VisieR search. I figure your star is XPM 246-0155519 second from the top in the list. The proper motions of 0.49 and 0.71 arcsecs/year for RA kind of match your estimate though I do not really get what these two numbers mean. (I think something to do with the accuracy of the values). 

Thanks Beka!

Very exciting but none of my browsers can display your scree shot.....

[beka]

The file upload does not seem to have worked maybe this time...

[gorann]

19 minutes ago, beka said:

The file upload does not seem to have worked maybe this time...

How did you get that image and what does the marks mean (red and green rings)? I can see it is from POSS2 due to that asteroid trace. The double star we are looking for is in the middle there but it is not marked.

[gorann]

Beka,

another thing. The unit for movement in the table is mas = milli arcseconds. So, when our  object moved 0.74 arcseconds that should be 740 mas

[gorann]

1 hour ago, gorann said:

How did you get that image and what does the marks mean (red and green rings)? I can see it is from POSS2 due to that asteroid trace. The double star we are looking for is in the middle there but it is not marked.

Beka,

I am trying to search the VizieR database and then press the Aladin icon to see it on a map. I am quite sure it is not the star you suggested (XPM 246-0155519), which seem to be the star just above. The problem is that there are so many lists and stars.

Here is a screen dump of the map with XPM 246-0155519 marked:

[gorann]

I think I found the double star!

The motion fits (sorry when I said 0.74 arcs/year, that was the other star in the image), I measured that the double star moves at 0.25 arcs/year = 250 mas/year. This one has the right coordinates, plots right on the Aladin sky atlas, and has about the right movement. In the USNO-B1.0 catalogue it has the identifier 1233-0118774

[gorann]

I now found it i several catalogues using the VizieR. They all have different identification numbers and I have so far not got a hit on Google (it mostly returns phone numbers, just had a hit on Indian doctors in Australia...)

Thanks Beka for pointing me at this server! - fun and frustrating

[beka]

1 hour ago, gorann said:

Beka,

I am trying to search the VizieR database and then press the Aladin icon to see it on a map. I am quite sure it is not the star you suggested (XPM 246-0155519), which seem to be the star just above. The problem is that there are so many lists and stars.

Here is a screen dump of the map with XPM 246-0155519 marked:

Yes that was the star I was referring to (though it is not the one highlighted in green)... I thought this was the object that you had said moved in your first post - towards the double star (looking back It looks like I had missed your mention of them being linked gravitationally). But yes I guess the proper motion for that one does not fit the observation while that of the double star does. Regarding the marks on the image, the red objects are all those found in the search and as you move the mouse pointer over the table, the object corresponding to that row is highlighted green on the picture. It is strange that the double star is not found and marked in the search of the XPM catalog. Maybe the catalog is only for fainter stars, Anyway it was an interesting exercise and I think you finally nailed the identity of the object of your interest - congrats. Maybe you can try further to determine if it is mentioned anywhere as a true gravitationally linked double star. Also I do not see information on the distance and spectral class in the catalog entry. Now what about your other object Gorann II... :-)

[gorann]

Beka,

dinner time and wife, so I have to get back later with the coordinates unless you have time to get them yourself. Here is the image with it marked our to the left. Moving at 0.74 arcs/year

Now+POSS1+2 Arrows.tif

[ollypenrice]

Briefly back to geostationary satellites, they are geostaionary so they will produce more or less point like images on a static mount while the stars trail, but on a tracking mount they will produce trails while the stars are point-like.

Olly

[gorann]

38 minutes ago, ollypenrice said:

Briefly back to geostationary satellites, they are geostaionary so they will produce more or less point like images on a static mount while the stars trail, but on a tracking mount they will produce trails while the stars are point-like.

Olly

Yes, Olly you are perfectly right, and in any case the first images of these objects are from around 1950 (POSS1 survey), before even the Russians got any Sputnik up.

[gorann]

So friends,

This was an exciting learning experience!

I finally nailed the double star to the right down. It is a binary system, i.e. two stars that are gravitationally pulled together and rotate around each other (apparently very slowly in this case since they do not show an angular change 62 years - too slow for my intuition). The small one is a white dwarf. The name is WD0518-333. It is even mentioned in a paper in The Astronomical Journal in 1996 (vol 111m issue 6, p. 2000-2016 by I. Neill Reid:  White Dwarf Masses - Gravitational Redshifts Revisited). You find it here:

http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1996AJ....111.2000R&classic=YES

So Beka, should we hunt the other one down? I will track down its coordinates now.

Cheers!

 

[gorann]

By the way, I got so entangled in this that I forgot to do a proper processing of the initial NGC1893 (Tadpoles) image, but now I have made a try:

[gorann]

16 hours ago, beka said:

Yes that was the star I was referring to (though it is not the one highlighted in green)... I thought this was the object that you had said moved in your first post - towards the double star (looking back It looks like I had missed your mention of them being linked gravitationally). But yes I guess the proper motion for that one does not fit the observation while that of the double star does. Regarding the marks on the image, the red objects are all those found in the search and as you move the mouse pointer over the table, the object corresponding to that row is highlighted green on the picture. It is strange that the double star is not found and marked in the search of the XPM catalog. Maybe the catalog is only for fainter stars, Anyway it was an interesting exercise and I think you finally nailed the identity of the object of your interest - congrats. Maybe you can try further to determine if it is mentioned anywhere as a true gravitationally linked double star. Also I do not see information on the distance and spectral class in the catalog entry. Now what about your other object Gorann II... :-)

So, Beka, here are the coordinates for the object to the right (in 1988, so it will have moved a bit): RA 05 23 11, Dec +33 11 10. It moves on RA at abut 740 mas/year

I am off to bed soon but will have a go at it tomorrow, so if you feel like it please beat me to it

[Shibby]

On 24/02/2017 at 17:34, Uranium235 said:

Blimey! Back from the dead  haven't seen you about in ages mate (pardon the digression).

Hey Rob! Yeah certainly been busy for a while but recently moved house and am planning an observatory... permission has been granted ? Hope you've been keeping well.

Sorry if this is and hijack - glad you've identified your stellar mysteries gorann!

[gorann]

15 minutes ago, Shibby said:

Hey Rob! Yeah certainly been busy for a while but recently moved house and am planning an observatory... permission has been granted ? Hope you've been keeping well.

Sorry if this is and hijack - glad you've identified your stellar mysteries gorann!

Rob & Lewis!

Glad you found each other, and good luck with the obsy Lewis!

Cheers

[Uranium235]

45 minutes ago, Shibby said:

Hey Rob! Yeah certainly been busy for a while but recently moved house and am planning an observatory... permission has been granted ? Hope you've been keeping well.

Sorry if this is and hijack - glad you've identified your stellar mysteries gorann!

Good luck with the obsy mate, hope you get to do some imaging again soon now is probably a good time for building and tinkering with all this awful weather.

Quite a bit has changed, new gear, new baby, now got wheels too! Hope to see you at SGL XIII if you can make it (dont forget, theyre held in the autumn now) might need your help with the processing workshops ive been running for the past few years (an extra pair of hands is always welcome!).

[beka]

5 hours ago, gorann said:

So, Beka, hear are the coordinates for the object to the right (in 1988, so it will have moved a bit): RA 05 23 11, Dec +33 11 10. It moves on RA at abut 740 mas/year

I am off to bed soon but will have a go at it tomorrow, so if you feel like it please beat me to it

My Internet was bad last night, maybe will try today.

Best