Non-sidereal tracking file on Subaru OCS

To track a target of non-sidereal movement, i.e. Solar System objects, the telescope control system (TCS) needs right ascension (RA), declination (Dec), and geocentric distance to the target for the time period during which observation will take place. TCS accepts a file for each target for each run or each night.

Subaru Software Division has prepared simplified procedures to create non-sidereal tracking files. An observer can either

Using JPL Horizons

Coordinate files created by the JPL HORIZONS System can be converted at the telescope site to be supplied to the TCS. Please supply the following parameters to the HORIZONS System. Observers may want to specify Time Span for each night with 1 minute Step Size.

Ephemeris TypeOBSERVER
Observer LocationGeocentric [500]
Table Settings1. Astrometric RA & DEC, 20. Observer range & range-rate
Display/Outputplain text or download/save

Please bring the created files to the observatory or send them to the support astronomer.

The files should be uploaded to the observation control system (OCS) by the support astronomer. The files can be loaded to the Gen2 Integrated GUI then to to the TCS by following the menu: File - Load source - eph then pushing the button Convert and Copy to TSC* on the page viewer that appears when the file is loaded.

At the telescope

At the telescope, observers may use the Gen2 Integrated GUI to query coordinates of the target to the JPL HORIZONS System. Supply the name of the planet, planetary moon, asteroid, or comet to the input box next to the SolarSystemObject button in the TELESCOPE tab in the launcher pane in the lower left corner of the GUI.

Once the Gen2 Integrated GUI receives the answer from the JPL HORIZONS System, two viewer pages appear in the pane in the lower right corner of the GUI. Please select the .tsc tab and push Copy to TSC button to transfer the file to the TCS.

At Hale Pohaku

In the Subaru Office at Hale Pohaku, an observer has access to the observatory network but not to the Gen2 Integrated GUI. An observer may use commands logging into one of the servers from OCS to create non-sidereal tracking files.

jplHorizons

jplHorizons command queries the JPL HORIZONS System for coordinates through the name of a target. Please SSH to the host sumda.sum.subaru.nao.ac.jp by using your o-account and run the command. In the example below, start and end dates are specified in UTC while increments are specified in minutes. 

$ jplHorizons -t Ceres --start=2013-04-30 --end=2013-05-01 --incr=60 --out=Ceres.tsc

The command-line options for jplHorizons are as follows:

If the specified target name matches more than one item in the database, you will receive a prompt asking you to select the specific target desired.

All date/time entries are UTC and can be YYYY-MM-DD HH:MM:SS, YYYYMMDD-HH:MM:SS, YYYYMMDD.DDDDD, JD, or MJD

nstrack

For targets which is not on the JPL HORIZONS System database, nstrack command may be used to specify orbital elements. Please SSH to the host sumda.sum.subaru.nao.ac.jp by using your o-account and run the command.o 

$ nstrack --asteroid --epoch=2455400.5 \
--orbinc=10.58682 --Om=80.3932 --om=72.58981 --a=2.7653485 --e=0.07913825 --M=113.4104434 \
--start "2012-09-01 04:00" --end "2012-09-01 06:00" --out=Ceres.tsc --comment "Ceres on 2012-09-01"

The command-line options for nstrack are as follows:

Note that the combination of --planet and --name can be used to specify either the name of a planet or the name of a planetary satellite, e.g., Deimos, Phobos, etc. See below for a complete list of recognized planetary satellites.

You can also place all the target information into a text file and then use the --infile=<INFILE> option to tell nstrack to read the information from the specified file. The input file contains the same attribute/value pairs that you would specify on the command-line. An example input file might look like this: 

asteroid
name=Ceres
start='2012-09-01 04:00'
end='2012-09-01 06:00'
out=Ceres.out
comment="Ceres on 2012-09-01"

All date/time entries are UTC and can be YYYY-MM-DD HH:MM:SS, YYYYMMDD-HH:MM:SS, YYYYMMDD.DDDDD, JD, or MJD

Other methods

There are some more options an observer can follow to create non-sidereal tracking files and/or bulk-transfer them. Please refer to the Non-Sidereal Targets which unfortunately only accessible from the observatory's network at the Hilo facility, in the Hale PoHaku office, or the telescope control building.

You may also wan to to refer to the traditional procedure.

Footnote

TCS and TSC
It is confusing but TCS stands for the Telescope Control System while TSC, being one of the computers in TCS, stands for the Telescope Supervise Computer.
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