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  #1  
Old 05-02-2009, 04:49 AM
alphajuno (Dave)
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Missing Star?

I was looking for minor planets last night and noticed that a star that the GSC catalog said was supposed to be in a certain spot was missing. I confirmed that supposed location matches the on-line catalog - so it's not my software only. Does that happen often? Do I report it somewhere? Thanks. I usually just find stuff I can't identify...
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Last edited by alphajuno; 05-02-2009 at 04:53 AM. Reason: added on-line search result
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  #2  
Old 05-02-2009, 10:17 AM
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Does the catalogue entry in the GSC actually call it a star or a "non star"
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  #3  
Old 05-02-2009, 10:33 AM
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Quark (Trevor)
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Hi Dave,

Maybe it is a variable star, what mag was it supposed to be?

Trevor
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  #4  
Old 05-02-2009, 10:43 PM
Enchilada
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Post Gsc 780:424

Position for this star is 08h 00m 13.42s +08 deg 29' 36.5" (J2000), whose presumed magnitude is 11.7+/-0.4. The star is question is likely non-existent and is probably a position fault in the catalogue.
It isn't an asteroid, because it does not appear on the original image from which the GSC was created, nor on several other images takes in different colours and epochs.
It cannot be a variable, as the six images I looked at using ALADIN.
By linking with images some twenty years apart, shows no sign of some high proper motion star.
Possibility a nova, but more likely it is an positional error or star duplication in the GSC. GSC 1 does not say this is a "non-star" or error.
No star is list in the GSC 2.3 or Tycho.

You can quickly check the origin image at StSci website http://archive.stsci.edu/cgi-bin/dss_form yourself, and do the following;
  • Type in the RA and Dec
  • Select HST Phase 2 (GSC1) in the "Retrieve from" menu
  • Set the width and height (15x15 is usually adequate)
  • Change the file format to gif, as you can view the image on the screen) or download it as fits format. (the latter requires a reader) In fits you can view the date the image was taken, which is in the header.

NOTE: The header look something like this, with the date in 1982.
SIMPLE = T /FITS: Compliance
BITPIX = 16 /FITS: I*2 Data
NAXIS = 2 /FITS: 2-D Image Data
NAXIS1 = 530 /FITS: X Dimension
NAXIS2 = 530 /FITS: Y Dimension
EXTEND = T /FITS: File can contain extensions
DATE = '2009-02-05 ' /FITS: Creation Date
ORIGIN = 'STScI/MAST' /GSSS: STScI Digitized Sky Survey
SURVEY = 'Pal-QV ' /GSSS: Sky Survey
REGION = 'N544 ' /GSSS: Region Name
PLATEID = '02V5 ' /GSSS: Plate ID
SCANNUM = '00 ' /GSSS: Scan Number
DSCNDNUM= '00 ' /GSSS: Descendant Number
TELESCID= 1 /GSSS: Telescope ID
BANDPASS= 1 /GSSS: Bandpass Code
COPYRGHT= 'STScI/AURA' /GSSS: Copyright Holder
SITELAT = 33.356 /Observatory: Latitude
SITELONG= 116.863 /Observatory: Longitude
TELESCOP= 'Palomar Schmidt ' /Observatory: Telescope
INSTRUME= 'Photographic Plate' /Detector: Photographic Plate
EMULSION= 'IIaD ' /Detector: Emulsion
FILTER = 'W12 ' /Detector: Filter
PLTSCALE= 67.20 /Detector: Plate Scale arcsec per mm
PLTSIZEX= 355.000 /Detector: Plate X Dimension mm
PLTSIZEY= 355.000 /Detector: Plate Y Dimension mm
PLATERA = 121.943324089 /Observation: Field centre RA degrees
PLATEDEC= 5.58078518020 /Observation: Field centre Dec degrees
PLTLABEL= 'ST326 ' /Observation: Plate Label
DATE-OBS= '1982-11-18T11:50 ' /Observation: Date/Time

Downloading the file finds the "GSC 780:424 is not there.

(This star is not listed in SIMBAD either)

I have attached four images for you;
  1. This colour composite of the same region
  2. Same image rotated in the orientation of your images
  3. Field charts showing the field using Megastar 5.0 showing GSC 780:424; limiting magnitude 16th.
  4. If used for the STSci star catalogue

If you have problems often like this, suggest you download and learn to use free Java ALADIN V5.019 jar software at; http://aladin.u-strasbg.fr/java/nph-...me=downloading
(Read the pdf manual to see how it applies to your application.)

Open Comment

Queries like this are more often than not always difficult to tie down.

I suggest if you would give some additional assistance it confirming evidence supporting your problem. (I've spent twenty minutes trying to identify the field and finding the missing star based on the minimal information you have given. I had to find Victoria (which isn't at the place image, then search the field - especially hard as your GSC 780-1016 is a so-called "non-star".)

At minimum we need;
1) When you discovered this problem (date and or time) and the circumstances
2) All the time and date of the image(s) in question. (Dates like 09-02-04 02:54 GMT are confusing, especially with US / British date formats. It is better to write times and dates in long form like;
4th February 2009 (04-02-09) at 02h 54m UT, so there is absolutely no confusion. In Australia by the way, the format should always be dd-mm-yy)
3) Field size and orientation of the image (Those presented are not aligned north-south)
4) Proper name or alternative names of the object
I.e. Guide Star Catalogue numbers are usually something like;
GSC 08510-01121 or GSC 0851001121 or (GSC 780:424 is meaningless)
See SIMBAD http://simbad.u-strasbg.fr/simbad/sim-fid , and input the ones above to see what I mean.
5) What is the RA, Dec and Epoch of the star/ object in question
6) What is the magnitude of the object
7) Approximate distance from some identifiable bright object

Please do not take this personally or me just being condescending, but if this was a significant discovery, few professional or amateur astronomers would just take little notice. Always make sure you give as much of the facts as necessary - even to the case of overkill, and what measures you have taken to verify the claim.
However, as you have properly done here, confirmation from an INDEPENDENT SOURCE is always advisable.
The thing I always find difficult, is once you found something, what do you do with the information?
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  #5  
Old 05-02-2009, 11:51 PM
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ngcles
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Missing star ??

Hi Alphajuno, Enchilada & All,

Nah!

Isn't it obvious to you all by now what is going on?

It is clearly a very early image of Nibiru that was released in the GSC before its significance was known but NASA (who later realised what it was) came along and doctored all the pics to hide it from the public.

You can all see that ... clear as day ... surely ??


Best,

Les D

BTW, We need an emoticon for "tongue-in-cheek" -- whistle was as close as I could find but still not quite right.

Last edited by ngcles; 06-02-2009 at 12:44 AM.
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  #6  
Old 05-02-2009, 11:58 PM
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renormalised (Carl)
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Talking

Quote:
It is clearly a very early image of Nibiru that was released in the GSC before its significance was known but NASA (who later realised what it was) came along and doctored all the pics to hide it from the public
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  #7  
Old 06-02-2009, 12:45 AM
Enchilada
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Question

I think I'm a little bit dense or am just thinking a bit slow, because I know Babylonian god of Nibiru was a pseudoscientific planetary object was described by Zecharia Sitchin, but I can't quite see the point of the humour. (Perhaps the missing planet Vulcan have been a little esoteric?)

To reiterate, clearly; "It isn't an asteroid, because it does not appear on the original image from which the GSC was created, nor on several other images takes in different colours and epochs."
The GSC catalogue was lifted from Schmidt images. If the star isn't on the plate, it is therefore neither an asteroid or star - confirmed with nothing at the location with other plates.
Sadly spending just a few frustrating hours look at various images and internet and on-hand databases certainly doesn't lend to much levity from my point of view at the moment. Perhaps I should have instead done something else - well maybe next time.
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  #8  
Old 06-02-2009, 12:56 AM
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renormalised (Carl)
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But Vulcan orbits 40 Eri a (Omicron 2 Eridani a ), and that's only 16ly away!!!

I know, because Spock told me so

After our lunch with Adm. Kirk
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  #9  
Old 06-02-2009, 12:57 AM
Enchilada
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Exclamation

Very gentle reminder here. As formally stated under the "Astronomy Science" in the thread header... "Strictly moderated - stay on-topic, serious discussions please." (I have enough problems already appeasing the dictates of the moderators without further assistance, please...)
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  #10  
Old 06-02-2009, 04:59 AM
alphajuno (Dave)
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Thanks for tracking that down for me. I tried pulling from the newer GSC database (I only suceeded in the older version) but I guess I didn't enter data in the right format because I kept getting a null return. I've saved your suggestions for posting things like this and I'll fool around with the db some more. Looks like it was just a catalog error that was corrected later - thanks.

And, I guess I need to search again for 12 Victoria. I thought it might be fun to try since the moon was out. Not sure why I didn't find it (the photo was taken on 4th February 2009 (04-02-2009) at 02h 54m UT which was a little earlier than the attachment) although I have lots of noise in the center of my images due to the moon/light pollution (maybe). But that's something that I should be able to figure out after the moon gets out of the way. I did catch 2006 AS2 that night but it was not in the center of the view. More to learn...

Thanks again!
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  #11  
Old 06-02-2009, 05:21 AM
Enchilada
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The plot thickens...

In looking for GSC 780:424, I did a more deeper search, and found that the star is listed in The HST Guide Star Catalog, Version 1.1 (Lasker+ 1992), and 1.3 (GSC-ACT) but the catalogued epoch date is 1984.889, while the GSC 1.0 says 1982! Yet in the VizieR search for the star in version 1.0, I now get the error ;
The following problems were encountered in this VizieR run:
****SIMBAD Error for object 'GSC 0078000424': This identifier is not present in the database: GSC 00780-00424

Bizarre.

Furthermore in the GSC 2.2, 2.2.1, 2.2.3, the star no longer exists and seems the deletion has not been documented! So I'd say this is simply an error.

Checking again using asteroid ephemerides for 1984.889, there seems no bright asteroid of 11.7 magnitude anywhere near this location.

The last option is to look for the plate for 1984.889 - but perhaps tomorrow!

Last edited by Enchilada; 06-02-2009 at 05:36 AM.
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