• Processing (Info)

    • Satellite-Based Astrometry Format

    Astrometric observations made from space are stored in two 80-column records.

    The first record is identical to the format for ground-based optical observations, except that an "S" is stored in column 15.

    The format of the second record is as follows: 

       Columns       Use
   1 - 12        Identical to columns 1-12 of first record
  13             Blank (even if discovery observation)
  14             Note
  15             "s"
  16 - 32        Identical to columns 16-32 of first record
  33             "1" indicates that parallax information
                   is conveyed using the vector from the
                   geocenter to the spacecraft in km and with
                   respect to the equatorial J2000.0 system.
                 "2" indicates that parallax information
                   is conveyed using the vector from the
                   geocenter to the spacecraft in AU and with
                   respect to the equatorial J2000.0 system.

For parallax type "1":
  35 - 45        X component of vector (sign in column 35,
                   decimal point in column 41)
  47 - 57        Y component of vector (sign in column 47,
                   decimal point in column 53)
  59 - 69        Z component of vector (sign in column 59,
                   decimal point in column 65)

For parallax type "2":
  35 - 45        X component of vector (decimal point in
                   column 37)
  47 - 57        Y component of vector (decimal point in
                   column 49)
  59 - 69        Z component of vector (decimal point in
                   column 61)

  70 - 77        Blank, must contain spaces (ASCII 32)
  78 - 80        Observatory code
  
    Note that for distances in km greater than 100,000 km, or in au
greater than 10 au, the decimal point will be shifted right by one
column. The au format must be used if any offset is greater than
ten million kilometers.

    Example Observations

    The first Hubble Space Telescope observation of 1222 T-1 published on MPC 26225: 
                                        Column
         1         2         3         4         5         6         7         8
123456789 123456789 123456789 123456789 123456789 123456789 123456789 123456789

     T1S1222  S1995 10 19.53839 23 45 35.737+09 09 38.13                     250
     T1S1222  s1995 10 19.53839 1 + 5530.3041 - 4255.1515 -  550.2319        250
    Gaia observations of (619987) published on MPC 162021: 
                                         Column
         1         2         3         4         5         6         7         8
123456789 123456789 123456789 123456789 123456789 123456789 123456789 123456789
				    
z9987K06UJ8Y  S2019 07 26.24274223 37 30.822-17 07 24.24                ~3GcZ258
z9987K06UJ8Y  s2019 07 26.2427421 + 551363.13 -1190783.85 - 650915.72   ~3GcZ258
    TESS observations of (127) published on MPC 162021: 
                                         Column
1         2         3         4         5         6         7                  8
123456789 123456789 123456789 123456789 123456789 123456789 123456789 123456789
				     
00127         S2019 12 25.03083306 52 11.700+35 03 49.93         11.9 GV~6Eu3C57
00127         s2019 12 25.0308331 +121965.589 +32954.8990 +28915.0730   ~6Eu3C57