MMT Catalog Format Information
Observing Catalogs
Catalogs of targets should be prepared in advance of your observing run according to the format described below. The catalog will be loaded into the appropriate directory on the mount computer and verified for proper format. Catalogs of non-sidereal objects may be prepared in EDB format and submitted.
A description of the format and some example catalogs follow:
Observing Catalogs
Catalogs of targets should be prepared in advance of your observing run according to the format described below. The catalog will be loaded into the appropriate directory on the mount computer and verified for proper format. Catalogs of non-sidereal objects may be prepared in EDB format and submitted.
A description of the format and some example catalogs follow:
- The catalog should contain one line per object.
- Lines starting with a ‘#” are treated as comments and are ignored, as are blank lines.
- Lines starting with a ‘%” are used to indicate variations in our catalog format (such as adding a position angle column) and are described at the end of this document.
- Please make sure that your name, email address and the date of your observing run are included as comments at the top of the catalog.
- A line in a catalog file consists of the following 8 fields: ID, RA, DEC, RA proper motion, DEC proper motion, magnitude, spectral type, and epoch (in that order). Do not add additional fields unless it is one of the special catalog formats.
- The catalog format is “free form” (fields delimited by blanks or tabs) if the following guidelines are followed:
no field may contain embedded spaces;
no fields may be left blank, skipped, or omitted. - RA is in the format: hh:mm:ss.ss
- DEC is in the format: dd:mm:ss.s
- Proper motion for RA and DEC are in units of seconds of time per century and seconds of arc per century, respectively.
Please note that proper motions listed by Simbad have different units; they cannot be used straight out of the database. Entries must appear in both proper motion fields. If your objects have zero proper motion, enter 0.00 in both fields. - The visual magnitude and spectral type are for your information only – they could be replaced with, for example, redshift or some other notation, but there must be something in each of these fields unless they are suppressed as described below.
- The epoch is typically given as J2000.0.
Prior to August 2022, this served as both the epoch for proper motion calculations and the equinox for precession (so B1950 could be used). After August 2022, the mount code now assumes that coordinates are in J2000 (equivalent to ICRS). The epoch field can be used to specify the epoch of observation of the RA/Dec (eg 2015.5 for Gaia coordinates), but be alert for possible issues if a non-2000 epoch is used. - If a record in the catalog cannot be parsed free form, we take the first 15 characters as an object ID and then attempt to parse the rest of the record free form.
- If both of these attempts to allow free-form input fail (perhaps because the RA or DEC fields contain embedded blanks or the spectral type is missing, or almost anything), the parser will then try to fall back on our original strict specification,
which is to unpack the record using the following perl format:"A15 A13 A13 A8 A8 A6 A3 A9"
- As previously mentioned, lines starting with a “%” are used to allow variation from the above documented catalog format.
Such lines will be treated as comments unless they are one of those documented here.
These lines should appear at the top of the catalog file and will apply to the entire catalog.
At this time the following options are available:- %legacy This catalog uses the first 15 columns for object ID.
We recommend that all catalogs that use the original fixed field formatting include this line in their header. - %haspa This catalog has an extra column following the epoch which gives a position angle in degrees for each and every object. This value will be used to position the instrument rotator when a slew to that object is commanded. If no rotator motion is desired when moving to an object use the word “none” or just a dash “-” in the PA column.
Omit the %haspa and the PA column altogether if you do not want to rotator to move when the telescope slews to a any of your objects. - %nomag This catalog omits the visual magnitude field.
- %nospec This catalog omits the spectral type field.
- %nopm This catalog omits both proper motion fields.
- %epoch epoch This catalog uses the specified epoch for all objects and no epoch column is provided. See the example below.
- %legacy This catalog uses the first 15 columns for object ID.
- # The following is a valid observing catalog for use at the MMT.
# Howard Lester -- March 25, 2003 -- hlester@mmto.org
#
%legacy
FK5-0001 0:08:23.265 +29:05:25.58 +01.039 -016.33 2.06 A0 J2000.0
FK5-0002 0:09:10.695 +59:08:59.18 +06.827 -018.09 2.27 F5 J2000.0
FK5-0003 0:09:24.659 -45:44:50.79 +01.186 -018.11 3.88 K0 J2000.0
FK5-0004 0:10:19.257 +46:04:20.21 +00.074 +000.03 5.03 F0 J2000.0
FK5-0005 0:11:34.437 -27:47:59.12 +00.079 +001.65 5.42 K0 J2000.0
FK5-0006 0:11:44.014 -35:07:59.17 +01.412 +011.86 5.25 F5 J2000.0
FK5-0007 0:13:14.154 +15:11:00.80 +00.019 -001.20 2.83 B2 J2000.0
FK5-0009 0:19:25.674 -08:49:26.14 -00.093 -003.61 3.56 K0 J2000.0
FK5-0010 0:20:04.251 -64:52:29.25 +26.778 +116.39 4.23 F8 J2000.0
FK5-0011 0:25:45.056 -77:15:15.40 +66.919 +032.37 2.80 G0 J2000.0
FK5-0012 0:26:17.030 -42:18:21.81 +01.833 -039.57 2.39 K0 J2000.0
FK5-0013 0:30:02.362 -03:57:26.39 +00.074 -001.23 5.72 K5 J2000.0
FK5-0014 0:30:22.661 -23:47:15.72 -00.177 +001.27 5.19 A3 J2000.0 - # This is a catalog which omits magnitude and spectral type
# and which adds position angle (always 0.0 in this case)
# Tom Trebisky -- June 29, 2005 -- tom@mmto.org
#
%nomag
%nospec
%haspa
FK5-0001 0:08:23.265 +29:05:25.58 +01.039 -016.33 J2000.0 0.0
FK5-0002 0:09:10.695 +59:08:59.18 +06.827 -018.09 J2000.0 0.0
FK5-0003 0:09:24.659 -45:44:50.79 +01.186 -018.11 J2000.0 0.0
FK5-0004 0:10:19.257 +46:04:20.21 +00.074 +000.03 J2000.0 0.0
FK5-0005 0:11:34.437 -27:47:59.12 +00.079 +001.65 J2000.0 0.0
FK5-0006 0:11:44.014 -35:07:59.17 +01.412 +011.86 J2000.0 0.0
FK5-0007 0:13:14.154 +15:11:00.80 +00.019 -001.20 J2000.0 0.0
FK5-0009 0:19:25.674 -08:49:26.14 -00.093 -003.61 J2000.0 none
FK5-0010 0:20:04.251 -64:52:29.25 +26.778 +116.39 J2000.0 0.0
FK5-0011 0:25:45.056 -77:15:15.40 +66.919 +032.37 J2000.0 0.0
FK5-0012 0:26:17.030 -42:18:21.81 +01.833 -039.57 J2000.0 0.0
FK5-0013 0:30:02.362 -03:57:26.39 +00.074 -001.23 J2000.0 -
FK5-0014 0:30:22.661 -23:47:15.72 -00.177 +001.27 J2000.0 0.0 - # This is about the most concise catalog that would be useful.
# Homer Simpson -- December 1, 2005 -- homer@homer.org
%nomag
%nospec
%nopm
%epoch J2005.9
FK5-0001 0:08:23.265 +29:05:25.58
FK5-0002 0:09:10.695 +59:08:59.18
FK5-0003 0:09:24.659 -45:44:50.79
FK5-0004 0:10:19.257 +46:04:20.21
FK5-0005 0:11:34.437 -27:47:59.12
FK5-0006 0:11:44.014 -35:07:59.17
FK5-0007 0:13:14.154 +15:11:00.80
FK5-0009 0:19:25.674 -08:49:26.14
FK5-0010 0:20:04.251 -64:52:29.25
FK5-0011 0:25:45.056 -77:15:15.40
FK5-0012 0:26:17.030 -42:18:21.81
FK5-0013 0:30:02.362 -03:57:26.39
FK5-0014 0:30:22.661 -23:47:15.72
Direct comments or questions to Tom Trebisky.