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Image and Catalog Archive Guide/FAQ


Guide for the Image and Catalogue Archive

(Introduction | Guide | Service Notes | Interactive Search | VO Cone Search)


(Colors | Survey Plate Logs | Input Parameters | Catalogue File Formats | Image Log Format)


Colors

Brief discussion of the photographic colors of the survey plates.


Photographic Survey Plate Logs

As we add surveys to this server, we will add copies of the relevant plate logs here. The files are flat ASCII text, with one line per plate.

The file format looks like:

POSS-I
1st Epoch Palomar Obs. Sky Survey
NPlates=1974
0.000000 6.283185 -0.801280 1.570796

Field Plate   Date      Time  RA (B1950)     DEC RA  (J2000)    DEC Type  Filt    Exp H.A.   limits
0001      570 1952.6420 05.53 5.161811  1.570796 3.145701  1.567299 103aE RP2444   50 0:08W  0.000000 6.283185  1.487939  1.570796 se0001
0001      570 1952.6420 05.20 5.161811  1.570796 3.145701  1.567299 103aO None     10 0:13E  0.000000 6.283185  1.488308  1.570796 so0001
0002      567 1952.6393 08.53 5.894850  1.570796 3.145653  1.567299 103aE RP2444   50 0:16W  0.000000 6.283185  1.488066  1.570796 se0002
0002      567 1952.6393 09.50 5.894850  1.570796 3.145653  1.567299 103aO None     10 1:14E  0.000000 6.283185  1.488652  1.570796 so0002

The first 4 lines are just general survey info. The 1st line is the short survey title:

  • Surveys Currently on-line:
    1. POSSI = The 1st Palomar Observatory Sky Survey, including the Whiteoak extension.
    2. POSSII = The 2nd Palomar Observatory Sky Survey
    3. (SOUTH = SRCJ+ESOR+SERCEJ+SERCER)
      SRCJ = The 1st Epoch Southern Blue Survey (fields 1-606)
      ESOR = The 1st Epoch Southern Red Survey (fields 1-606)
      SERCEJ = The Southern Equatorial Blue Survey(fields 607-894)
      SERCER = The Southern Equatorial Red Survey (fields 607-894)
    4. AAOR = The 2nd Epoch Southern Red Survey
  • Surveys that will be on-line soon:
    1. AAON = The 2nd Epoch Southern Infra-Red Survey
    2. AAOSR = The South Galactic Plane Red Survey
    3. PIMWA = The North Galactic Plane Red and IR Survey
    4. LUYTEN = Luyten's 2nd Epoch Northern Sky Survey
    5. SPM = The Yale Southern Proper Motion Survey

The 2nd line is a longer descriptive title and the 3rd line gives the number of plates. Ignore the 4th and 5th lines. The 6th line is the header line, and is mostly descriptive. The plates start with line 7, and are ordered by survey field number (in the case of the SOUTH log, the 4 surveys are interleaved blue/red in the order SRC-J, SERC-EJ, ESO-R, SERC-ER).

Column        Description
------        -----------
 1            Survey field number (unique to the survey)
 2            Observatory plate id
 3            Plate observation date (UT)
 4            Plate observation time, MID-EXPOSURE, decimal hours (UT)
 5,6          RA, DEC (B1950) of plate center in RADIANS (from the
                      original observing log)
 7,8          RA, DEC (J2000) of plate center in RADIANS (precessed 
                      from the original observing log)
 9            Type is the Photographic Emulsion
10            Filt is the filter used with the exposure
11            Exp is the exposure time in minutes
12            Hour Angle of the observation, Mid-exposure
13,14,15,16   Rough RA,DEC limits for this plate, in RADIANS
                    ordered: minRA maxRA minDEC maxDEC
17            USNOFS database id for this plate

Additional notes:
 POSS-II:  the POSS-II log includes the observation data for the UJ
            (short J) plates.  However, the scan images were NOT
            saved, and currently are not available.

Search Tool Input Parameters

Field Name/ID
This field is included as an ID string on the upper left of finder charts and images. This field can be up to (3 lines x 36 characters/line =) 108 characters in length. A line break in this field can be set with "\n". For example "Line 1\nLine 2\nLine3" will show up as three lines. The "\n" will be removed by the server, and does not count against the character limit.
E-mail for image notification [Optional]
If you would like to be notified by e-mail when the server finishes retrieving the data you requested, please enter your e-mail address in this field. If no address is given, then you will want to check the links in the Image log periodically to see if there is anything there. The address should be in standard internet address format (e.g. name@host.domain). When retrieving image data, we HIGHLY RECOMMEND you use this feature, as the retrieval of images can take up a while (depending upon server load and the size of the region requested), and this way you will be notified when your data are available. Save yourself trouble later, ask for an e-mail notice.
RA
Right Ascension of the field center in hours - this can be entered in either decimal (hh.hhhh) or sexigesimal form (hh:mm:ss.ss or hh mm ss.ss).
Dec
Declination of the field center in degrees - can be entered in either decimal (dd.dddd) or sexigesimal form (dd:mm:ss.ss or dd mm ss.ss).
Equinox
J2000.0 or B1950.0. If the equinox and epoch you select are NOT those of the catalogue, the returned data will be precessed to the equinox and epoch you gave as input.
Epoch
A year between 1900 and 2100.
Field Size and Shape
The Size of the field may be specified in Degrees, Minutes or Seconds of arc. Also, you may choose to extract a rectangle or a circle about the center point. The circle applies only to the catalogue extraction. If you select a circle, the finder chart and the images will be the square that contains the circle.  The total area retrieved for catalog data also depends upon the Faint Magnitude limit.  The default maximum region A is a cone with a radius of 1.0 degrees or a box of 4 square degrees. If the Faint Magnitude limit is SMALLER than 25.0, then the allowed region area increases in size as A*2.5^[(25-Fmag)/4]. So, if you are only interested in objects down to 12 magnitude, the allowed region area increases in size by a factor of slightly over 19, or the maximum radius increases by a bit over 4. The hard upper limit in radius is 12 degrees.  For images, the maximum area is fixed at 45arcmin x 45arcmin.
RA Width
Field width in RA in units of arc. You get a rectangular finder chart or image. The maximum width for catalogs is currently limited to at most 24 degrees (see above discussion), and 45 arcminutes for image data.
DEC Width
Field width in DEC in units of arc. You get a rectangular finder chart or image. The maximum width for catalogs is currently limited to at most 24 degrees (see above discussion), and 45 minutes for image data.
Circle Radius
For a circular catalogue field, the radius in units of arc. The maximum radius is currently limited to 12 degrees for catalogue extractions and finder charts, and 22.5 minutes for image data.
Catalogue(s)
Select which catalogue(s) you would like to extract data from: NOMAD, USNO-B1.0, USNO-A2.0 and/or ACT. Tycho-2 and UCAC will be coming some time in the near future.
  1. Magnitude Limits Bright and Faint magnitude limits for extractions from the catalogue(s).
  2. Color Limits Blue minus Red color limits for extractions from the catalogue(s).  The default is B2-R2, but you can pick any pair of magnitudes to use.  Make sure that they exist in the catalog
  3. Color This choice determines which magnitude is used for sorting, and for the magnitude limits. The available options are B, V, R, B1, R1, B2, R2, I2, J, H, K. Not all catalogues have all colors, so you may see some behavior you don't understand. The colors decode as:
    • B = Blue
    • V = Visible
    • R = Red
    • B1 = First Epoch Blue
    • R1 = First Epoch Red
    • B2 = Second Epoch Blue
    • R2 = Second Epoch Red
    • I2 = Second Epoch Near IR
    • J = Near IR J band (2MASS)
    • H = Near IR H band (2MASS)
    • K = Near IR Ks band (2MASS)
    When using a color, the software looks for the closest string match to determine which color to use. Hence, if you ask for R2, and the catalogue only has B and R, it will use the R magnitude. Conversely, if you as for B, and the catalogue has B1 and B2, it will use the B1 magnitude, since it will find that first.
  4. Minimum Separation This option allows you to specify the minimum separation between objects in the extracted catalogue. This is given in decimal minutes of arc. [Not Enabled]
  5. Maximum Surface Density Trim the catalogue list(s) to a limit of at most this many objects per square degree.[Not Enabl
  6. Proper Motion Limits Specify the minimum and maximum proper motions of the objects to be included in the extracted catalogue (presuming that there is motion information). If a catalogue does not include proper motion, these selection criteria will be ignored. Units are milli-arcseconds per year.
Survey and Rejected Image Data
Select the photographic surveys you would like data to be extracted from. Currently available surveys are: POSS-I (2 colors), POSS-II (3 colors), SOUTH (ESO-R, SRC-J, SERC-EJ, SERC-ER) and AAO-R.
Coming soon: AAO-N, AAO-shortR, PIMWA (2 colors), Luyten's 2nd epoch survey (POSS-I field centers), SPM (2 colors), and UCAC. The Rejected images are additional plates that were taken for various surveys but for one reason or another were not included in the final survey.
Object List Options
  1. Star List Sort Options Select the parameter on which to sort the star lists. Options include RA, Dec, Magnitude, Color (Blue-Red), and Distance to Center. The list will be in increasing order.
  2. Star List Format Select your preferred format for RA and Dec. You can choose to not save the star lists at all, or have RA and Dec written out as:
    • hh mm ss.ss and dd mm ss.ss (sexigesimal hours and degrees)
    • hh:mm:ss.ss and dd:mm:ss.ss
    • hh.hhh and ddd.ddd (decimal hours and decimal degrees)
    • ddd.ddd and ddd.ddd (decimal degrees for both)
  3. Epoch Format Options Select desired format for printing the epoch of each plate that is listed with each detected object. The choices are decimal year (Julian Epoch) and Julian Date. This only applies to USNO-A2.0 at the moment.
Finder Chart and Image Options
  1. Overplot Star Lists (applies to Image data only) Indicate if you would like to have your list of catalogue stars overplotted on the images. If the number of stars is less than 100, the stars will be numbered with the catalogue id or a running index (USNO-A2.0).
  2. Dark Stars/Light Stars (applies to Image data only) You can choose whether you prefer light stars on a dark background or dark stars on a light background.  While Light Stars/Dark Sky looks more like the sky, it is often easier to see faint detail in the inverted image (Dark Stars/Light Sky), which is the default.
  3. Return FITS data file (applies to Image data only) If you request, the server will retrieve the FITS data file(s) of the image(s) as well. The images returned include a complete FITS image of the whole field.  The PMM images are digitized at 0.91 arcsec/pixel, so a region 10arcmin x 10arcmin, at 2 bytes per pixel will return an image file that is about 870KBytes.  A 30arcmin square field will be just under 2MBytes in size.  If you don't know what the FITS format is, odds are you don't want this. The default is no.
  4. Image Graphics Format This option allows you to choose what format you would like the chart and/or image to be. Your choices are (in order of increasing file size) Progressive JPEG, JPEG, GIF, Large JPEG, Large GIF and Postscript (NB: the last three options are restricted to one data from one survey, since the files are quite large). Not all image viewers can handle progressive JPEG files, so the default is JPEG. In general the JPEG file is about 1/4 the size of the GIF file, so please use that if possible.
  5. Plot Orientation This is your chance to pick the orientation of the chart (do you prefer East to the left and North down? we can do that).
  6. Coordinate Overlay You have three choices for marking the orientation of the chart or image. (1) Simple North and East markers (N and E on the respective sides, only available for images). (2) A set of RA and Dec tick marks along the edge of the image or chart bounding box. (3) An overlaid RA and Dec grid on the image or chart.
  7. Center Mark Choose whether you'd like to plot a square or circle at the center of the plot. For the square, the size is the WIDTH of the square, for the circle, this is the RADIUS.
  8. Additional Object(s) to Overplot
    • Optional Object This is the name of an optional object you wish to over plot on the finder chart. If the field is "none", then nothing will be over plotted, no matter what you put in the following fields. If you type in a name, then the program will examine the next two entry fields for the over plot data.
    • How to Plot Object You get your choice of just putting a point down, put a point down with a label, connect the points or connect and label the points
    • Big field to enter Object Data
    • WARNING: this overplot facility is very finicky! If the chart doesn't come out, odds are that there is a typo of some sort in the overplot data. The format for each line of object data is VERY specific. It expects the RA as hh mm ss.ss, then DEC as dd mm ss.ss then a Magnitude, a label of some sort, a plot color, and a symbol choice (which may take additional arguments). A sample line encoding an object at RA=1:23:45, Dec=-54:32:10.1, with magnitude=9.8, using a label=hi, and plotting a point (PNT) in red would be written:
                  1 23 45.0 -54 32 10.1 9.8 hi red PNT
      The available colors are:
      • default
      • white
      • black
      • red
      • green
      • blue
      • cyan
      • magenta
      • yellow
      There are several types of plot objects, each of which takes a different set of arguments:
      • PNT - plot a POINT, no arguments - uses an X point style.
      • SQR width - plot a SQUARE centered at the coordinates given, with a user specified width, 1 argument which is the width and height of the square.
      • CIR radius - plot a CIRCLE centered at the coordinates given, with with a user specified radius, 1 argument which is the radius.
      • REC height width - plot a RECTANGLE centered at the coordinates given, with with a user specified height and width, 2 arguments which are the height and width.
      • ELL semi-major_axis axis_ratio position_angle - plot an ELLIPSE centered at the coordinates given, with with a user specified semi-major axis, axis ratio (between 0 and 1) and position angle (measured North to East in degrees), 3 arguments which are the semi-major axis, the axis ratio, and the position angle.
            RA(J2000)   DEC(J2000)   Mag  Label  Color   Type  [r|a|e|pa]
             h  m  s     d  m  s     m    [str]  [str]   [str]
      
            00 59 00.0 -33 55 00.0   4.0  none   blue    PNT
            00 59 30.0 -33 50 00.0   8.0  8      blue    PNT
            01 00 00.0 -33 30 30.0  10.0  10     blue    PNT
            01 00 00.0 -33 35 00.0   5.0  A      blue    PNT
            01 00 01.0 -33 40 00.0  10.0  circle red     CIR 0.01667
            01 00 01.0 -33 40 10.0  10.0  circle red     CIR 360.0s
            01 00 02.0 -33 45 00.0   9.0  square default SQR 1.5m
            01 00 03.0 -33 50 00.0   1.0  rect   magenta REC 0.01667d 0.03333d
            01 00 03.0 -33 50 10.0   1.0  rect   magenta REC 1m     2m
            01 00 04.0 -33 55 00.0   9.0  ellip  blue    ELL 1m    0.5 -30
            01 00 04.0 -33 55 00.0   9.0  ellip  green   ELL 0.05d 0.2  30
      N.B.: The dimensions for the SQR and REC are the FULL WIDTH and/or HEIGHT, while the size for the CIR and ELL are the RADIUS and SEMI-MAJOR AXIS respectively. The sizes are in degrees by default, but if they are followed by a d, m or s they will be interpretted as being in degrees, minutes or seconds of arc respectively.
Compression
This flag allows you to choose whether or not the software compresses the output files (the star lists(s), and the postscript plot(s)) or leaves them as raw ASCII. The compression code used is GZIP. If your browser/machine has GZIP, your are advised to use the compression, but just in case, we make ASCII available too.

Catalogue Output Files and Formats (ASCII Format)

Header Format: All the catalogue data share a common file header format that gives details of the request that generated the subset of the catalogue. The syntax of each header line follows the pattern

#KEY = Value / Short Description or Comment
All header lines begin with a # to make it easy to remove them with text processing tools.

 

Here is a sample header:

#FIELD   = 'NoName'                     /Field Name                            
#CAT_ID  = 'USNOB'                      /Catalogue ID                          
#NOBJECTS= 129                          /Number of Objects In File             
#EQUINOX = J2000.0 2000.00              /Equinox, Epoch                        
#RA      = 0.000000                     /Center RA  [hrs]                      
#DEC     = 0.000000                     /Center DEC [deg]                      
#DRA     = 0.166667                     /Box Width  [deg]                      
#DDEC    = 0.166667                     /Box Height [deg]                      
#MAGNITUD= 'R2'                         /Primary Sort Color                    
#BR_MAG  = 0.00                         /Bright Magnitude Limit [mag]          
#FT_MAG  = 25.00                        /Faint Magnitude Limit [mag]           
#COLOR   = 'B2-R2'                      /Color0 minus Color1 (C0-C1)           
#BR_MIN  = -20.00                       /Color Limit: Min. C0-C1 [mag]         
#BR_MAX  = 20.00                        /Color Limit: Max. C0-C1 [mag]         
#MU_MIN  = 0.00                         /Min. Proper Motion [mas/yr]           
#MU_MAX  = 10000.00                     /Max. Proper Motion [mas/yr]           
#SPOS_MIN= 0.00                         /Min. Position Error [mas]             
#SPOS_MAX= 10000.00                     /Max. Position Error [mas]             
#SMU_MIN = 0.00                         /Min. Proper Motion Error [mas/yr]     
#SMU_MAX = 10000.00                     /Max. Proper Motion Error [mas/yr]     
#SD_MIN  = 0.00                         /Minimum Surface Density [N/deg^2]     
#SD_MAX  = 10000000.00                  /Maximum Surface Density [N/deg^2]     
#SEP_MIN = 0.000000 0.00                /Minimum Separation [deg] & [mag]       
#END

NOMAD1 Catalogue data is written out as a formatted ascii file. There is a 24 line header, followed by 3 lines of column headings followed by the data (detailed explanation of columns). See the NOMAD ReadMe File for more details about the catalogue.

An example is given here:

#FIELD   = 'NoName'                     /Field Name                             
#CAT_ID  = 'NOMAD'                      /Catalogue ID                           
#NOBJECTS= 136                          /Number of Objects In File              
#EQUINOX = J2000.0 2000.00              /Equinox, Epoch                         
#RA      = 0.000000                     /Center RA  [hrs]                       
#DEC     = 0.000000                     /Center DEC [deg]                       
#DRA     = 0.166667                     /Box Width  [deg]                       
#DDEC    = 0.166667                     /Box Height [deg]                       
#MAGNITUD= 'R2'                         /Primary Sort Color                     
#BR_MAG  = 0.00                         /Bright Magnitude Limit [mag]           
#FT_MAG  = 100.00                       /Faint Magnitude Limit [mag]            
#COLOR   = 'B2-R2'                      /Color0 minus Color1 (C0-C1)            
#BR_MIN  = -100.00                      /Color Limit: Min. C0-C1 [mag]          
#BR_MAX  = 100.00                       /Color Limit: Max. C0-C1 [mag]          
#MU_MIN  = 0.00                         /Min. Proper Motion [mas/yr]            
#MU_MAX  = 10000.00                     /Max. Proper Motion [mas/yr]            
#SPOS_MIN= 0.00                         /Min. Position Error [mas]              
#SPOS_MAX= 10000.00                     /Max. Position Error [mas]              
#SMU_MIN = 0.00                         /Min. Proper Motion Error [mas/yr]      
#SMU_MAX = 10000.00                     /Max. Proper Motion Error [mas/yr]      
#SD_MIN  = 0.00                         /Minimum Surface Density [N/deg^2]      
#SD_MAX  = 10000000.00                  /Maximum Surface Density [N/deg^2]      
#SEP_MIN = 0.000000 0.00                /Minimum Separation [deg] & [mag]       
#END                                                                            
           id|           RA|          DEC|sra|sde|   MuRA|  MuDEC|  sMuRA|  sMuDE|   Flags|      B|      V|      R|      J|      H|      K|          Xi|         Eta|       Gal_L|       Gal_B|DistCtr|
           id|     hh mm ss|     dd mm ss|mas|mas| mas/yr| mas/yr| mas/yr| mas/yr|     hex|    mag|    mag|    mag|    mag|    mag|    mag|      arcsec|      arcsec|     ddd.ddd|     ddd.ddd| arcsec|
 0900-0000001 00 00 00.0687 +00 04 38.110  77  87    20.0     8.0     3.0     4.0      209  20.590   0.000  19.770   0.000   0.000   0.000        1.030      278.110   96.3995755  -60.1177948   278.1 
 0899-0000001 00 00 00.6260 -00 03 55.070 734 229     0.0     0.0     0.0     0.0      209  17.940   0.000  15.420   0.000   0.000   0.000        9.390     -235.070   96.2896627  -60.2494731   235.3 
 0899-0000002 00 00 00.8160 -00 04 37.820 109  84   -26.0   -20.0     5.0     4.0      209  20.910   0.000  19.820  16.251  15.762  15.654       12.240     -277.820   96.2815723  -60.2606771   278.1 
 0899-0000003 00 00 00.8193 -00 03 55.200 214  85     0.0     0.0     0.0     0.0      201   0.000   0.000  18.700   0.000   0.000   0.000       12.290     -235.200   96.2911221  -60.2498277   235.5

USNO-B1.0 Catalogue data is written out as a formatted ascii file. There is a 24 line header, followed by 3 lines of column headings followed by the data (detailed explanation of columns). See Monet, D. et al. 2003, AJ, 125, 948 for details about the catalogue and its construction.

An example is given here:

#FIELD   = 'NoName'                     /Field Name                            
#CAT_ID  = 'USNOB'                      /Catalogue ID                          
#NOBJECTS= 129                          /Number of Objects In File             
#EQUINOX = J2000.0 2000.00              /Equinox, Epoch                        
#RA      = 0.000000                     /Center RA  [hrs]                      
#DEC     = 0.000000                     /Center DEC [deg]                      
#DRA     = 0.166667                     /Box Width  [deg]                      
#DDEC    = 0.166667                     /Box Height [deg]                      
#MAGNITUD= 'R2'                         /Primary Sort Color                    
#BR_MAG  = 0.00                         /Bright Magnitude Limit [mag]          
#FT_MAG  = 25.00                        /Faint Magnitude Limit [mag]           
#COLOR   = 'B2-R2'                      /Color0 minus Color1 (C0-C1)           
#BR_MIN  = -20.00                       /Color Limit: Min. C0-C1 [mag]         
#BR_MAX  = 20.00                        /Color Limit: Max. C0-C1 [mag]         
#MU_MIN  = 0.00                         /Min. Proper Motion [mas/yr]           
#MU_MAX  = 10000.00                     /Max. Proper Motion [mas/yr]           
#SPOS_MIN= 0.00                         /Min. Position Error [mas]             
#SPOS_MAX= 10000.00                     /Max. Position Error [mas]             
#SMU_MIN = 0.00                         /Min. Proper Motion Error [mas/yr]     
#SMU_MAX = 10000.00                     /Max. Proper Motion Error [mas/yr]     
#SD_MIN  = 0.00                         /Minimum Surface Density [N/deg^2]     
#SD_MAX  = 10000000.00                  /Maximum Surface Density [N/deg^2]     
#SEP_MIN = 0.000000 0.00                /Minimum Separation [deg] & [mag]       
#END                                                                           
          id|           RA|          DEC|sra|sde|         Epoch|  MuRA| MuDEC|MuProb| sMuRA| sMuDE|sFitRA|sFitDE|NFitPt| Flags|     B1|MagFlg|S/G|     R1|MagFlg|S/G|     B2|MagFlg|S/G|     R2|MagFlg|S/G|     I2|MagFlg|S/G|          Xi|         Eta|       Gal_L|       Gal_B|DistCtr|
          nd|     hh mm ss|     dd mm ss|mas|mas|     yyyy.yyyy|mas/yr|mas/yr|    nd|mas/yr|mas/yr|   mas|   mas|    nd|    nd|    mag|    nd| nd|    mag|    nd| nd|    mag|    nd| nd|    mag|    nd| nd|    mag|    nd| nd|      arcsec|      arcsec|     ddd.ddd|     ddd.ddd| arcsec|
0899-0627200 23 59 42.7173 -00 02 02.150 999 999    1951.600000      0      0      0      0      0    900    900      2      0  19.770      2   4  19.830      2   3   0.000      0  19   0.000      0  19   0.000      0  19     -259.240     -122.150   96.1772101  -60.1908854   286.6 
0899-0627199 23 59 41.5273 -00 01 15.020 184 999    1951.600000      0      0      0      0      0    200    900      2      0  20.740      2   2  19.880      2   4   0.000      0  19   0.000      0  19   0.000      0  19     -277.090      -75.020   96.1786220  -60.1769038   287.1 
0899-0000028 00 00 07.1340 -00 02 25.880 999 459    1972.200000      0      0      0      0      0    900    600      2      0   0.000      0  19  19.110      2   2  19.170      2   6   0.000      0  19   0.000      0  19      107.010     -145.880   96.3596680  -60.2375601   180.9 
0899-0627202 23 59 42.8653 -00 02 13.650 999 692    1965.600000     64   -285      9    119     17    900    600      3      0  20.300      2   7  19.550      2   3   0.000      0  19   0.000      0  19  17.320      2  19     -257.020     -133.650   96.1757720  -60.1940593   289.7

USNO-A2.0 Catalogue data is written out as a formatted ascii file. There is a 24 line header, followed by 3 lines of column headings followed by the data (detailed explanation of columns). An example is given here:

#FIELD   = 'NoName'                     /Field Name                            
#CAT_ID  = 'USNOA2'                     /Catalogue ID                          
#NOBJECTS= 44                           /Number of Objects In File             
#EQUINOX = J2000.0 2000.00              /Equinox, Epoch                        
#RA      = 0.000000                     /Center RA  [hrs]                      
#DEC     = 0.000000                     /Center DEC [deg]                      
#DRA     = 0.166667                     /Box Width  [deg]                      
#DDEC    = 0.166667                     /Box Height [deg]                      
#MAGNITUD= 'R2'                         /Primary Sort Color                    
#BR_MAG  = 0.00                         /Bright Magnitude Limit [mag]          
#FT_MAG  = 25.00                        /Faint Magnitude Limit [mag]           
#COLOR   = 'B2-R2'                      /Color0 minus Color1 (C0-C1)           
#BR_MIN  = -20.00                       /Color Limit: Min. C0-C1 [mag]         
#BR_MAX  = 20.00                        /Color Limit: Max. C0-C1 [mag]         
#MU_MIN  = 0.00                         /Min. Proper Motion [mas/yr]           
#MU_MAX  = 10000.00                     /Max. Proper Motion [mas/yr]           
#SPOS_MIN= 0.00                         /Min. Position Error [mas]             
#SPOS_MAX= 10000.00                     /Max. Position Error [mas]             
#SMU_MIN = 0.00                         /Min. Proper Motion Error [mas/yr]     
#SMU_MAX = 10000.00                     /Max. Proper Motion Error [mas/yr]     
#SD_MIN  = 0.00                         /Minimum Surface Density [N/deg^2]     
#SD_MAX  = 10000000.00                  /Maximum Surface Density [N/deg^2]     
#SEP_MIN = 0.000000                     /Minimum Separation [deg]              
#END                                                                           
          id|           RA|          DEC|ErrFlg| Flags|      B|      R|          Xi|         Eta|       Gal_L|       Gal_B|DistCtr|
          nd|     hh mm ss|     dd mm ss|    nd|    nd|    mag|    mag|      arcsec|      arcsec|     ddd.ddd|     ddd.ddd| arcsec|
           1 00 00 02.5293 -00 04 21.530      0      -  14.400  13.400       37.940     -261.530   96.2984080  -60.2593771   264.3 
           2 00 00 04.1540 -00 01 56.320      0      -  18.300  17.100       62.310     -116.320   96.3433141  -60.2250835   132.0 
           3 00 00 04.6973 -00 03 24.590      0      -  17.700  16.900       70.460     -204.590   96.3278163  -60.2484745   216.4 
          23 00 00 04.8047 +00 03 36.200      0      -  18.200  16.200       72.070      216.200   96.4222121  -60.1414178   227.9 
           4 00 00 05.9893 -00 02 46.360      0      -  17.600  15.100       89.840     -166.360   96.3462905  -60.2408792   189.1 
          24 00 00 06.8760 +00 02 29.710      0      -  18.400  17.000      103.140      149.710   96.4233848  -60.1617959   181.8

ACT Catalogue data is written out as a formatted ascii file. There is a 24 line header, followed by 3 lines of column headings followed by the data (detailed explanation of columns). An example is given here:

#FIELD   = 'NoName'                     /Field Name                            
#CAT_ID  = 'ACT'                        /Catalogue ID                          
#NOBJECTS= 2                            /Number of Objects In File             
#EQUINOX = J2000.0 2000.00              /Equinox, Epoch                        
#RA      = 0.000000                     /Center RA  [hrs]                      
#DEC     = 0.000000                     /Center DEC [deg]                      
#DRA     = 0.166667                     /Box Width  [deg]                      
#DDEC    = 0.166667                     /Box Height [deg]                      
#MAGNITUD= 'R2'                         /Primary Sort Color                    
#BR_MAG  = 0.00                         /Bright Magnitude Limit [mag]          
#FT_MAG  = 25.00                        /Faint Magnitude Limit [mag]           
#COLOR   = 'B2-R2'                      /Color0 minus Color1 (C0-C1)           
#BR_MIN  = -20.00                       /Color Limit: Min. C0-C1 [mag]         
#BR_MAX  = 20.00                        /Color Limit: Max. C0-C1 [mag]         
#MU_MIN  = 0.00                         /Min. Proper Motion [mas/yr]           
#MU_MAX  = 10000.00                     /Max. Proper Motion [mas/yr]           
#SPOS_MIN= 0.00                         /Min. Position Error [mas]             
#SPOS_MAX= 10000.00                     /Max. Position Error [mas]             
#SMU_MIN = 0.00                         /Min. Proper Motion Error [mas/yr]     
#SMU_MAX = 10000.00                     /Max. Proper Motion Error [mas/yr]     
#SD_MIN  = 0.00                         /Minimum Surface Density [N/deg^2]     
#SD_MAX  = 10000000.00                  /Maximum Surface Density [N/deg^2]     
#SEP_MIN = 0.000000 0.00                /Minimum Separation [deg] & [mag]       
#END                                                                           
          id|           RA|          DEC|  MuRA| MuDEC|      B|      V|          Xi|         Eta|       Gal_L|       Gal_B|DistCtr|
          nd|     hh mm ss|     dd mm ss|mas/yr|mas/yr|    mag|    mag|      arcsec|      arcsec|     ddd.ddd|     ddd.ddd| arcsec|
          17 00 00 08.9786 -00 03 53.249  -5669  -8630  11.435  10.735      134.679     -233.249   96.3544033  -60.2628828   269.3 
      199563 23 59 59.7660 -00 03 55.179    944   -700  11.800  10.489       -3.510     -235.179   96.2830174  -60.2480706   235.2

For each photographic plate in the archive that matches all your selection criteria, you will receive a log file line, with a link to the image itself. The line will look like:

      No. Survey Field Plate   Date      Time  RA (B1950)     DEC RA  (J2000)   DEC Type  Filt    Exp H.A.   dbID   Nimg
jpg   001 POSSI  0585      319 1951.6071 10.40 0.021235  0.009231 0.029289 0.012727 103aE RP2444   50 0:18E  se0585 0002
jpg   002 POSSI  0585      319 1951.6071 10.15 0.021235  0.009231 0.029289 0.012727 103aO None     10 0:28E  so0585 0002

The columns are as follows:

  • The leading column will contain the link to the image, and the character string will indicate the type of graphics file (jpg = JPEG, gif = GIF, ps = Postscript, ps.gz = gzipped Postscript, FITS=FITS, etc.).
  • The column headed NO. is just an index.
  • SURVEY indicates which survey the image came from:
    • POSSI = The 1st Palomar Observatory Sky Survey, including the Whiteoak extension.
    • POSSII = The 2nd Palomar Observatory Sky Survey
    • SRCJ = The 1st Epoch Southern Blue Survey
    • ESOR = The 1st Epoch Southern Red Survey
    • SERCEJ = The Southern Equatorial Blue Survey
    • SERCER = The Southern Equatorial Red Survey
    • AAOR = The 2nd Epoch Southern Red Survey
    • AAON = The 2nd Epoch Southern Infra-Red Survey
    • AAOSR = The South Galactic Plane Red Survey
    • PIMWA = The North Galactic Plane Red and IR Survey
    • LUYTEN = Luyten's 2nd Epoch Northern Sky Survey
  • FIELD gives the survey field number.
  • PLATE is the inventory plate ID for the photographic plate. Not surprisingly, each observatory has its own system.
  • DATE is the UT date when the plate was taken, and is given in decimal years.
  • TIME is in decimal hours UT, and is at mid-exposure.
  • RA/DEC (B1950) gives the nominal center (as recorded in the observing log, NOT based on the plate solution) of the plate in B1950 coordinates. The RA and DEC are given in RADIANS.
  • RA/DEC (J2000) gives the nominal center (as recorded in the observing log, NOT based on the plate solution) of the plate in J2000 coordinates. The RA and DEC are given in RADIANS.
  • TYPE gives the type of emulsion used on the photographic plate.
  • FILT gives the Filter used during the exposure. The combination of the emulsion and the Filter determine the effective bandpass of the system.
  • EXP lists the length of the exposure in MINUTES.
  • H.A. gives the hour angle at mid-exposure.
  • DBID is the database id name for this plate, and is the string on the side of each image returned.
  • NIMG is the number of PMM ``footprints'' (individual images of the plate) that went into constructing this particular image.

Last updated: 2008Dec18 by sel
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