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#title=true ra=true dec=true epoch=false muRA=true muDec=true magnitude=true dRA=true dDec=true rotatorPA=true rotatorFrame=true comment=true
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"Vega - Alpha Lyrae" 18:36:56.336 +38:47:01.28 200.94 286.23 0.03 1.0 2.0 3.0 Target "line 1"
"HR 173 - HD 3795" 00:40:32.809 -23:48:17.56 635.18 -363.56 6.14 1.0 2.0 3.0 Fixed "line 2"

Title, Right Ascension, and Declination are required parameters and the rest are optional. The first line of the meta data declares which parameters will be supplied in the input file. The order of the columns cannot change and the only thing that can be edited in the first line is the true/false value for the column. In other words, the first line has to include all the parameters shown above. The second line is a simple separator and is also required.

The input parameters are:

  • title or name (surrounded in double quotes) - required - it will be sent to the TCS as the science target name and cannot be blank
  • Right Ascension (hh:mm:ss.sss) - required - the seconds can be either integer or float
  • Declination (+/-dd:mm:ss.ss) - required - plus sign is optional for the degrees, and arc-seconds can be either integer or float
  • Proper Motion in RA (mas/yr) - this is the angular measurement used by most catalogs: μα×cos(δ)
  • Proper Motion in Dec (mas/yr) - μδ
  • Magnitude
  • differential tracking rate in RA (arc seconds/hour)
  • differential tracking rate in DEC (arc seconds/hour)
  • rotator Postion Angle (degrees)
  • rotator Frame ("Target" or "Fixed") - a literal string without the quotes
  • comment (surrounded in double quotes) - A convenience column for observer's use

The coordinates need to be in FK5 (J2000). Not all combinations of optional data make sense and the code is not robust enough to check for all the possible combinations. For instance; proper motion in RA and DEC should be supplied together. 

The fields should all be separated by at least one space and the columns in the input file do not have to line up but extra spaces can be inserted so that they are more readable for the user. Magnitude is included in case the observer wishes to sort the table based on brightness. It is not used by the TCS and it is not sent as part of the command. The comment field is for the observer's convenience to include notes to make the table more user friendly. The value in this field is not sent to the TCS. 

The table can be sorted by clicking on the column headers. First click does an ascending sort. Second click does a descending sort and third click reverts to original order.

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Every table includes three extra columns which are computed for DCT based on the current time; Air Mass, Azimuth, Elevation and ElevationTime of Transit. These columns are provided to aid the observer in target selection and are time dependent. A re-sort of any of the columns causes the data to be recalculated and the updated values are shown.

The Air Mass column can also be computed for a specified time of day. Right clicking on the table brings up the dialog box for entering the time (local) for the calculation. The column will be refreshed and the font color changes to blue to indicate that the air mass is not for current time. Re-sorting any of the columns will override the calculations and reverts back to current air mass.

The tooltips for all the computed column headers show the time when the calculation was performed.

Inline Editing

The first displayed line in the table (ID=0) is basically a blank like to offer the user the opportunity to send a target to the TCS that was not included in the input file. All the columns except ID and the computed columns are editable but one has to make sure that the edited column has been accepted by the app.

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As with other cases, it is essential to double check the values in the top panel before sending the target to the TCS. The act of editing does not cause the target to be selected and the edits are not reflected in the top panel automatically. In order to select the edited target one has to click on another row and then click back on the edited row to select it.

Another way to generate a target in real time is to use the "Editable Target View" button on the bottom right of the top panel. This generates a new view (tab) with one editable row in it, same as the first line in other windows. Functionally there is no difference between this view and the first line of a loaded target list. It is simply there in case an observer does not already have a target list and does not wish to load one of the built-in standard lists.

Sky Plot

Clicking on the "Sky Plot" buttons brings up a polar plot of AZ vs EL (north is up) for the current table. Selecting a target on the plot highlights the row on the table. One has to remember that this plot is time dependent and the Update button will refresh it with current values. The only difference between the two buttons is the window size of the plot.

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Example Input Data

The simplest input file includes title, RA and DEC which are the minimal required data for the TCS.

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More may be added soon. Some of these files contain many thousands of sources and take quite a long time to load.

Clear Offsets

The "Clear Offsets" button sends a command to TCS to clear both user and handset offsets on the TCS. This can also be accomplished but asking the operator to clear the offsets. This button is more useful to observers on instruments that were not built at Lowell. The instrument control software for the in-house instruments already includes widgets for sending and clearing offsets.