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TCS Catalogue Format
If you have a long list of objects to observe, you'll probably want to create your own catalogue before the observing run. The telescope operator then doesn't need to type in the coordinates each time you want to move the telescope, which will make observing more efficient.
NAME ra(hh mm ss.ss) dec(dd mm ss.ss) equinox
where NAME can have up to 20 characters (no embedded spaces) and equinox specifies the equinox of the source coordinates ("B1950", "J2000" or "APPARENT"). The names and the RA and Dec should not end with a '.', e.g. 'M31.' or '12 58 43.'.
Note that coordinates in the ICRS system (e.g. those from Gaia) should have their equinox specified as J2000 - do not use the epoch of the catalogue (e.g. 2015.5). The J2000 and ICRS coordinates of an object differ by < 0.1 arcsec.
M33   01 33 51.02  30 39 36.70   J2000
Optionally, proper motions can be added after the column for the equinox. Three numbers should be specified: right ascension proper motion in seconds per year, declination proper motion in arcseconds per year and epoch of coordinates, as in these examples:
ZEN07 02 43 27.112 +27 42 25.68 J2000.0 0.0006 -0.012 2000.0
Note the distinction between equinox and epoch. The equinox determines the coordinate system used, usually J2000. The epoch is the date on which the object was at the quoted RA and Dec. Sometimes the epoch is the actual date when the object's position was measured, sometimes it's a prediction for some standard date (e.g. 2000), based on the known proper motion, and a measured position at some other time.
Other information that can be added to the catalogue entry, following the column for the epoch of proper motion, are parallax (in arcseconds), radial velocity (in km/s) and comments (following a '!', as in this example:
Please note the following:
This page is maintained by Lilian Dominguez.
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