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Telling the Telescopes Where to Go: Coordinate...(1Jun92)
Transfers Make it to the Mountain
(from KPNO, NOAO Newsletter No. 30, 1 June 1992)

For astronomers who have a large number of objects to observe and would
like to have coordinates loaded before their run, this article is for
you.  Indeed, any observer who makes extensive use of coordinate caches
should follow these procedures, as last minute entry of coordinates can
lead to chaos with things not going in the smooth manner we would
like.

Coordinate lists may be sent via e-mail at least two weeks before your
observing run to coords@noao.edu. Files should be ASCII text, no longer
than 2000 lines. For ease of use we suggest breaking large files into
smaller ones.  Start your file with your name, a cache name, telescope,
and dates of your observing run. Coordinates will be checked for
format, loaded into the appropriate telescope computer, and an
acknowledgement sent to you that all is ready for your arrival.

Each object in the file should be on one line of text. The format for
data entry is object name (which will be truncated to twelve characters
by some of the telescope control computers), right ascension (starting
in column 16 or greater, delimited by the first blank after column 15;
hours, minutes, seconds), declination (degrees, minutes, seconds), and
epoch. Each field should be separated by one or more spaces. Do not use
tabs. The delimiter in the RA and Dec fields may be either spaces or
colons. Decimals are permitted in both the seconds of RA and Dec
entries.

For example:

            alpha Lyr  18:36:21.70 +38:46:02.0 1983.0

Note that the right ascension must start in column 16 or greater and
that the sign of the declination must be adjacent to the declination
degrees (i.e. -6 and -06 are allowed, but - 6 is not).

Users of the 2.1-m telescope can take advantage of the ability of the
telescope control program in use there to apply proper motion
corrections. This feature will be added to the telescope control
programs at other telescopes as they are upgraded. Proper motion in
right ascension and declination (arcsec per year) may be added to
entries after the epoch field. For example:

         HD 172167  18 36 21.7 +38 46 02 1983 +0.20 +0.28

While this would be valid data entry for files that can be loaded at
any telescope, the proper motion correction would be ignored everywhere
but at the 2.1-m at present.

If you have edited or added to your object cache during your observing
run and wish to have your cache e-mailed to you after the run, send the
request to coords@noao.edu. The telescope computers should not be used
for long-term storage of your coordinate files.

More extensive instructions and options for the data  format are
available by e-mailing to coords@noao.edu with a request for complete
documentation. We would also be interested in your thoughts for the
future of this service.

Coordinate lists have been around for decades in various formats. At
this time we do not do paper tape, punch cards, or magnetic tape.

Bruce Bohannan, Paul Harding,
Jean Nowakowski, David Chamberlin

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