JWST General Target Visibility Tool Help
The JWST General Target Visibility Tool (GTVT) is a command-line Python tool that provides quick-look assessments of target visibilities and position angles for all JWST instruments.
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See also: JWST Moving Target Visibility Tool Help, JWST Position Angles, Ranges, and Offsets, JWST Target Observability and Observatory Coordinate System
The JWST General Target Visibility Tool (GTVT) is a Python command-line tool for calculating target visibility windows as a function of time. The GTVT is one of 3 primary tools for investigating JWST target visibilities.
For a given RA and Dec, the GTVT provides aperture position angle (APA) information for all 4 science instruments and the FGS within the allowed visibility windows. It also outputs the V3-axis position angle (V3PA). Results are in the form of an ASCII file as well as one or more summary plots. A number of options are available from the command line for tailoring the output to your needs. Once the interactive plot is displayed, icons can be selected to pan and zoom in on the plot to see detailed information.
The GTVT contains an optional branch that permits the easy inclusion of moving targets instead of just fixed coordinate targets. See JWST Moving Target Visibility Tool Help for more information on this option.
The schedulability of a given target observation is more complex than just its visibility. It also involves the availability of guide stars as a function of time and other constraints that may be set with special requirements in APT. The GTVT is a "quick look" tool for pre-planning purposes, but the Astronomers Proposal Tool is the true arbiter of schedulability for a given proposed observation.
Dependencies
Words in bold are GUI menus/
panels or data software packages;
bold italics are buttons in GUI
tools or package parameters.
numpy, matplotlib, astropy, astroquery, pysiaf, docopt, pandas, and tabulate. Use thepip install [PACKAGE]
command (where PACKAGE is one of the dependencies listed above) to assess whether it is installed. If not already installed, the pip command will do so. If some or all of the dependencies are not already installed, the pip command will also install the dependencies.
Installation and usage
The GTVT is currently incompatible with Windows operating systems.
You can install the tool using pip with: pip install jwst-gtvt
Alternatively, you can clone the repository from the GitHub jwst_gtvt repository and install the tool from inside the resulting directory with "pip install -e .". (The period in the command is required and is not punctuation.)
Conda environments are also provided:
$ conda env create -f environment_python_3.10.yml
$ conda activate jwst-gtvt-3.10'
$ pip install -e .Usage tips
To see the GTVT help information, type jwst_gtvt -h or jwst_gtvt --help
$ jwst_gtvt -h
Usage:
jwst_gtvt --ra=<ra> --dec=<dec> [--start_date=<obs_start>] [--end_date=<obs_end>] [--instrument=<inst>] [--target_name=<name>] [--write_ephemeris=<write_path>] [--write_plot=<plot_path>] [--silent]
Arguments:
--ra=<ra> Right ascension of target to observe with JWST.
--dec=<dec> Declination of target to observe with JWST.
Options:
[--start_date] Start date for plot
[--end_date] End date for plot
[--instrument] JWST instrument to plot individually
[--target_name] User provided name for target
[--write_ephemeris] File name to write ephemeris to
[--write_plot] File name to write plot out to
[--silent] Boolean to print results to screen [default: False]
-h --help Show this screen.
--version Show version.
The --version flag is currently subject to a bug where the version output is that of the docopt package, rather than the version of the GTVT itself. If you type jwst_gtvt --version and you do not receive an error, you are using version 1.0 or greater, since the --version flag was not available previously. This issue will be fixed in a future update.
GTVT command line examples
When using GTVT in the command line, you only need to specify RA and Dec (the default input values). Observability windows are shown in the terminal and plots of visibility windows for each instrument are displayed. However, there are other useful command-line options, as shown in the examples below; each command is followed by a text description.
jwst_gtvt --ra=325.678 --dec=43.586 --target_name "SS Cyg"
This command runs and produces an interactive visibility plot on the screen for all instruments. No files are saved to disk. Note that enclosing the target name in quotes allows for spaces in the text. To exit the program, close the plot window. Alternatively, if you want access to the terminal window from which the tool was run prior to exiting the program, add an ampersand "&" at the end of the command-line entry above to run the program in the background.
jwst_gtvt --ra=325.678 --dec=43.586 --target_name "SS Cyg" --write_plot SSCyg_all.png
This command only saves a plot to a file; no interactive plot is displayed.
jwst_gtvt --ra=325.678 --dec=43.586 --target_name "SS Cyg" --instrument v3pa --write_plot SSCyg_v3.png
This command shows a single instrument panel for (in this case) the V3PA. The allowed values for --instrument are nircam, nirspec, niriss, miri, fgs, and v3pa (case insensitive). To exit the program, close the plot window.
jwst_gtvt --ra=325.678 --dec=43.586 --target_name "SS Cyg" --write_ephemeris SSCyg.dat
This command produces a plot on the screen for all 4 science instruments, the FGS, and the V3 position angle. Tabular data are sent to a file instead of being displayed on the screen. To exit the program, close the plot window.
jwst_gtvt --ra=325.678 --dec=43.586 --target_name "SS Cyg" --write_plot SSCyg_all.jpg --write_ephemeris SSCyg1.dat
This command saves both outputs to the specified files; there is no interactive plot.
jwst_gtvt --ra=325.678 --dec=43.586 --target_name "SS Cyg" --start_date 2023-07-01 --end_date 2024-06-30
An interactive plot is displayed for all 4 science instruments, the FGS, and the V3 position angle, starting on July 1, 2023, and running for one year. To exit the program, close the plot window.
The example below shows the top portion of the ASCII output from a simple run of the GTVT (first command in this section). The top section provides a summary of the target and windows, and the bottom table (truncated) shows the day-by-day minimum and maximum allowed angles in each of the visibility windows for the 4 science instruments, the FGS, and the V3 position angle. The nominal angles are approximately midway between the 2 limits shown.
jwst_gtvt --ra=325.678 --dec=43.586 --target_name "SS Cyg" +------------------------------------------+ | JWST General Target Visibility Tool | +------------------------------------------+ | Runtime/Date: 2023-07-05 21:06:00.158119 | +------------------------------------------+ | Version Number: 1.0.0 | +------------------------------------------+ RA: 325.678 Dec: 43.586 Ecliptic Latitude: 24.284867 ------------------------------------------------------------- Checked Interval [2021-12-26 00:00:00.000, 2025-06-11 00:00:00.000] +--------------------------------+--------------------------------+-------------------+------------------+----------------+ | Window Start | Window End | Window Duration | V3 Angle Start | V3 Angle End | |--------------------------------+--------------------------------+-------------------+------------------+----------------| | A.D. 2022-Jun-04 00:00:00.0000 | A.D. 2022-Dec-21 00:00:00.0000 | 200 | 243.612 | 51.4104 | | A.D. 2023-Jun-04 00:00:00.0000 | A.D. 2023-Dec-22 00:00:00.0000 | 201 | 243.823 | 50.8514 | | A.D. 2024-Jun-04 00:00:00.0000 | A.D. 2024-Dec-21 00:00:00.0000 | 200 | 243.28 | 51.0963 | | A.D. 2025-Jun-04 00:00:00.0000 | A.D. 2025-Jun-11 00:00:00.0000 | 7 | 243.503 | 238.204 | +--------------------------------+--------------------------------+-------------------+------------------+----------------+ +--------------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+-------------+-------------+ | NRC Max PA | NRC Min PA | NRS Max PA | NRS Min PA | NIS Max PA | NIS Min PA | MIR Max PA | MIR Min PA | FGS Max PA | FGS Min PA | V3 Max PA | V3 Min PA | |--------------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+--------------+-------------+-------------| | 247.093 | 239.989 | 25.7389 | 18.6348 | 247.726 | 240.621 | 252 | 244.896 | 245.923 | 238.819 | 247.164 | 240.06 | | 246.685 | 238.865 | 25.3307 | 17.5113 | 247.317 | 239.498 | 251.592 | 243.772 | 245.515 | 237.696 | 246.756 | 238.937 | | 246.279 | 237.743 | 24.9245 | 16.3891 | 246.911 | 238.376 | 251.185 | 242.65 | 245.109 | 236.573 | 246.35 | 237.815 | | 245.874 | 236.622 | 24.5203 | 15.2679 | 246.507 | 237.255 | 250.781 | 241.529 | 244.704 | 235.452 | 245.946 | 236.693 | | 245.472 | 235.502 | 24.1178 | 14.1475 | 246.105 | 236.134 | 250.379 | 240.408 | 244.302 | 234.332 | 245.543 | 235.573 | | 244.83 | 234.623 | 23.4758 | 13.2689 | 245.463 | 235.256 | 249.737 | 239.53 | 243.66 | 233.453 | 244.901 | 234.694 | | 244.069 | 233.865 | 22.7149 | 12.5112 | 244.702 | 234.498 | 248.976 | 238.772 | 242.899 | 232.695 | 244.14 | 233.937 | | 243.309 | 233.108 | 21.9553 | 11.7539 | 243.942 | 233.741 | 248.216 | 238.015 | 242.14 | 231.938 | 243.381 | 233.179 | | 242.551 | 232.351 | 21.1969 | 10.9967 | 243.184 | 232.983 | 247.458 | 237.258 | 241.381 | 231.181 | 242.622 | 232.422 | | 241.794 | 231.594 | 20.4395 | 10.2394 | 242.426 | 232.226 | 246.7 | 236.5 | 240.624 | 230.424 | 241.865 | 231.665 | | 241.037 | 230.836 | 19.6829 | 9.48201 | 241.67 | 231.469 | 245.944 | 235.743 | 239.867 | 229.666 | 241.108 | 230.907 | | 240.281 | 230.078 | 18.927 | 8.72425 | 240.914 | 230.711 | 245.188 | 234.985 | 239.111 | 228.908 | 240.352 | 230.15 | | 239.526 | 229.32 | 18.1716 | 7.96598 | 240.158 | 229.953 | 244.433 | 234.227 | 238.356 | 228.15 | 239.597 | 229.391 | | 238.771 | 228.561 | 17.4166 | 7.20705 | 239.403 | 229.194 | 243.677 | 233.468 | 237.601 | 227.391 | 238.842 | 228.632 | | 238.016 | 227.801 | 16.6618 | 6.44729 | 238.648 | 228.434 | 242.923 | 232.708 | 236.846 | 226.632 | 238.087 | 227.873 | | 237.261 | 227.041 | 15.9069 | 5.68654 | 237.894 | 227.673 | 242.168 | 231.947 | 236.091 | 225.871 | 237.332 | 227.112 | | 236.506 | 226.279 | 15.152 | 4.92464 | 237.139 | 226.911 | 241.413 | 231.186 | 235.336 | 225.109 | 236.577 | 226.35 | | 235.751 | 225.516 | 14.3967 | 4.16143 | 236.383 | 226.148 | 240.658 | 230.422 | 234.581 | 224.346 | 235.822 | 225.587 | | 234.995 | 224.751 | 13.641 | 3.39674 | 235.628 | 225.383 | 239.902 | 229.658 | 233.825 | 223.581 | 235.066 | 224.822 | | 234.239 | 223.984 | 12.8847 | 2.63042 | 234.871 | 224.617 | 239.146 | 228.891 | 233.069 | 222.815 | 234.31 | 224.056 | | 233.482 | 223.216 | 12.1275 | 1.8623 | 234.114 | 223.849 | 238.388 | 228.123 | 232.312 | 222.047 | 233.553 | 223.288 | | 232.724 | 222.446 | 11.3695 | 1.09222 | 233.356 | 223.079 | 237.63 | 227.353 | 231.554 | 221.276 | 232.795 | 222.518 | | 231.964 | 221.674 | 10.6102 | 0.320015 | 232.597 | 222.307 | 236.871 | 226.581 | 230.794 | 220.504 | 232.036 | 221.745 | | 231.204 | 220.9 | 9.84975 | 359.546 | 231.836 | 221.532 | 236.111 | 225.806 | 230.034 | 219.73 | 231.275 | 220.971 | | 230.442 | 220.123 | 9.0878 | 358.769 | 231.074 | 220.755 | 235.349 | 225.029 | 229.272 | 218.953 | 230.513 | 220.194 | | 229.678 | 219.343 | 8.32423 | 357.989 | 230.311 | 219.976 | 234.585 | 224.25 | 228.508 | 218.173 | 229.75 | 219.415 | | 228.913 | 218.561 | 7.55888 | 357.207 | 229.546 | 219.193 | 233.82 | 223.468 | 227.743 | 217.391 | 228.984 | 218.632 | | 228.146 | 217.776 | 6.79159 | 356.422 | 228.778 | 218.408 | 233.052 | 222.682 | 226.976 | 216.606 | 228.217 | 217.847 | | 227.376 | 216.987 | 6.02218 | 355.633 | 228.009 | 217.62 | 232.283 | 221.894 | 226.206 | 215.817 | 227.448 | 217.059 | | 226.605 | 216.196 | 5.25048 | 354.842 | 227.237 | 216.828 | 231.511 | 221.103 | 225.435 | 215.026 | 226.676 | 216.267 | | 225.83 | 215.401 | 4.47633 | 354.047 | 226.463 | 216.033 | 230.737 | 220.308 | 224.661 | 214.231 | 225.902 | 215.472 | | 225.054 | 214.602 | 3.69957 | 353.248 | 225.686 | 215.235 | 229.96 | 219.509 | 223.884 | 213.432 | 225.125 | 214.673 | | 224.274 | 213.8 | 2.92001 | 352.446 | 224.907 | 214.432 | 229.181 | 218.707 | 223.104 | 212.63 | 224.345 | 213.871 | | 223.492 | 212.994 | 2.1375 | 351.639 | 224.124 | 213.626 | 228.398 | 217.9 | 222.322 | 211.824 | 223.563 | 213.065 | | 222.706 | 212.183 | 1.35187 | 350.829 | 223.339 | 212.816 | 227.613 | 217.09 | 221.536 | 211.013 | 222.777 | 212.255 | | 221.917 | 211.369 | 0.562933 | 350.015 | 222.55 | 212.001 | 226.824 | 216.276 | 220.747 | 210.199 | 221.988 | 211.44 | | 221.125 | 210.55 | 359.771 | 349.196 | 221.757 | 211.182 | 226.031 | 215.457 | 219.955 | 209.38 | 221.196 | 210.621 | | 220.329 | 209.726 | 358.974 | 348.372 | 220.961 | 210.359 | 225.235 | 214.633 | 219.159 | 208.556 | 220.4 | 209.798 | | 219.529 | 208.898 | 358.175 | 347.544 | 220.161 | 209.531 | 224.436 | 213.805 | 218.359 | 207.728 | 219.6 | 208.969 | | 218.725 | 208.065 | 357.371 | 346.711 | 219.358 | 208.698 | 223.632 | 212.972 | 217.555 | 206.895 | 218.796 | 208.136 | | 217.917 | 207.227 | 356.563 | 345.873 | 218.55 | 207.86 | 222.824 | 212.134 | 216.747 | 206.057 | 217.988 | 207.298 | | 217.105 | 206.384 | 355.751 | 345.03 | 217.737 | 207.016 | 222.011 | 211.29 | 215.935 | 205.214 | 217.176 | 206.455 | | 216.288 | 205.535 | 354.934 | 344.181 | 216.92 | 206.168 | 221.195 | 210.442 | 215.118 | 204.365 | 216.359 | 205.606 | | 215.466 | 204.681 | 354.112 | 343.327 | 216.099 | 205.313 | 220.373 | 209.588 | 214.297 | 203.511 | 215.538 | 204.752 | | 214.64 | 203.821 | 353.286 | 342.467 | 215.273 | 204.454 | 219.547 | 208.728 | 213.47 | 202.651 | 214.712 | 203.892 | | 213.809 | 202.955 | 352.455 | 341.601 | 214.441 | 203.588 | 218.716 | 207.862 | 212.639 | 201.786 | 213.88 | 203.027 | | 212.972 | 202.084 | 351.618 | 340.73 | 213.605 | 202.716 | 217.879 | 206.991 | 211.803 | 200.914 | 213.044 | 202.155 | | 212.131 | 201.206 | 350.777 | 339.852 | 212.763 | 201.839 | 217.037 | 206.113 | 210.961 | 200.036 | 212.202 | 201.277 | | 211.283 | 200.322 | 349.929 | 338.968 | 211.916 | 200.955 | 216.19 | 205.229 | 210.113 | 199.152 | 211.355 | 200.393 | | 210.43 | 199.432 | 349.076 | 338.078 | 211.063 | 200.064 | 215.337 | 204.338 | 209.26 | 198.262 | 210.502 | 199.503 | | 209.572 | 198.535 | 348.217 | 337.181 | 210.204 | 199.167 | 214.478 | 203.441 | 208.402 | 197.365 | 209.643 | 198.606 | | 208.707 | 197.631 | 347.353 | 336.277 | 209.339 | 198.264 | 213.613 | 202.538 | 207.537 | 196.461 | 208.778 | 197.702 | | 207.836 | 196.72 | 346.482 | 335.366 | 208.468 | 197.353 | 212.742 | 201.627 | 206.666 | 195.551 | 207.907 | 196.792 | | 206.958 | 195.803 | 345.604 | 334.449 | 207.591 | 196.436 | 211.865 | 200.71 | 205.789 | 194.633 | 207.03 | 195.874 | | 206.075 | 194.878 | 344.72 | 333.524 | 206.707 | 195.511 | 210.981 | 199.785 | 204.905 | 193.709 | 206.146 | 194.95 | | 205.184 | 193.947 | 343.83 | 332.592 | 205.817 | 194.579 | 210.091 | 198.853 | 204.014 | 192.777 | 205.255 | 194.018 | | 204.287 | 193.007 | 342.933 | 331.653 | 204.919 | 193.64 | 209.194 | 197.914 | 203.117 | 191.838 | 204.358 | 193.079 | | 203.383 | 192.061 | 342.029 | 330.707 | 204.015 | 192.693 | 208.289 | 196.968 | 202.213 | 190.891 | 203.454 | 192.132 | | 202.471 | 191.107 | 341.117 | 329.753 | 203.104 | 191.739 | 207.378 | 196.013 | 201.301 | 189.937 | 202.543 | 191.178 | | 201.553 | 190.145 | 340.199 | 328.791 | 202.185 | 190.777 | 206.46 | 195.051 | 200.383 | 188.975 | 201.624 | 190.216 | | 200.627 | 189.175 | 339.273 | 327.821 | 201.259 | 189.808 | 205.534 | 194.082 | 199.457 | 188.005 | 200.698 | 189.246 | | 199.693 | 188.198 | 338.339 | 326.843 | 200.326 | 188.83 | 204.6 | 193.104 | 198.524 | 187.028 | 199.765 | 188.269 | | 198.752 | 187.212 | 337.398 | 325.858 | 199.385 | 187.845 | 203.659 | 192.119 | 197.582 | 186.042 | 198.824 | 187.283 | | 197.803 | 186.219 | 336.449 | 324.864 | 198.436 | 186.851 | 202.71 | 191.125 | 196.634 | 185.049 | 197.875 | 186.29 | | 196.847 | 185.217 | 335.493 | 323.863 | 197.479 | 185.85 | 201.754 | 190.124 | 195.677 | 184.047 | 196.918 | 185.288 | | 195.882 | 184.207 | 334.528 | 322.853 | 196.515 | 184.84 | 200.789 | 189.114 | 194.712 | 183.037 | 195.953 | 184.278 | | 194.909 | 183.189 | 333.555 | 321.835 | 195.542 | 183.822 | 199.816 | 188.096 | 193.739 | 182.019 | 194.981 | 183.26 | | 193.928 | 182.163 | 332.574 | 320.809 | 194.561 | 182.796 | 198.835 | 187.07 | 192.758 | 180.993 | 194 | 182.234 | | 192.939 | 181.128 | 331.585 | 319.774 | 193.572 | 181.761 | 197.846 | 186.035 | 191.769 | 179.959 | 193.01 | 181.2 | | 191.941 | 180.086 | 330.587 | 318.731 | 192.574 | 180.718 | 196.848 | 184.992 | 190.772 | 178.916 | 192.013 | 180.157 | | 190.935 | 179.034 | 329.581 | 317.68 | 191.568 | 179.667 | 195.842 | 183.941 | 189.766 | 177.865 | 191.007 | 179.106 | | 189.921 | 177.975 | 328.567 | 316.621 | 190.553 | 178.608 | 194.828 | 182.882 | 188.751 | 176.805 | 189.992 | 178.046 | | 188.898 | 176.907 | 327.544 | 315.553 | 189.53 | 177.54 | 193.805 | 181.814 | 187.728 | 175.737 | 188.969 | 176.979 | | 187.866 | 175.831 | 326.512 | 314.477 | 188.499 | 176.464 | 192.773 | 180.738 | 186.696 | 174.661 | 187.937 | 175.903 | | 186.826 | 174.747 | 325.472 | 313.393 | 187.459 | 175.38 | 191.733 | 179.654 | 185.656 | 173.577 | 186.897 | 174.818 | | 185.777 | 173.655 | 324.423 | 312.301 | 186.41 | 174.287 | 190.684 | 178.562 | 184.607 | 172.485 | 185.848 | 173.726 | | 184.72 | 172.554 | 323.365 | 311.2 | 185.352 | 173.187 | 189.626 | 177.461 | 183.55 | 171.384 | 184.791 | 172.626 | | 183.653 | 171.446 | 322.299 | 310.092 | 184.286 | 172.078 | 188.56 | 176.353 | 182.484 | 170.276 | 183.725 | 171.517 | | 182.579 | 170.33 | 321.225 | 308.975 | 183.211 | 170.962 | 187.486 | 175.236 | 181.409 | 169.16 | 182.65 | 170.401 | | 181.496 | 169.205 | 320.142 | 307.851 | 182.128 | 169.838 | 186.402 | 174.112 | 180.326 | 168.036 | 181.567 | 169.277 | | 180.404 | 168.074 | 319.05 | 306.72 | 181.037 | 168.706 | 185.311 | 172.98 | 179.234 | 166.904 | 180.475 | 168.145 | | 179.304 | 166.934 | 317.95 | 305.58 | 179.937 | 167.567 | 184.211 | 171.841 | 178.134 | 165.765 | 179.375 | 167.006 | | 178.196 | 165.788 | 316.841 | 304.434 | 178.828 | 166.42 | 183.102 | 170.695 | 177.026 | 164.618 | 178.267 | 165.859 | | 177.079 | 164.634 | 315.725 | 303.28 | 177.712 | 165.267 | 181.986 | 169.541 | 175.909 | 163.464 | 177.15 | 164.705 | | 175.954 | 163.473 | 314.6 | 302.119 | 176.587 | 164.106 | 180.861 | 168.38 | 174.784 | 162.303 | 176.026 | 163.545 | | 174.822 | 162.306 | 313.468 | 300.952 | 175.454 | 162.939 | 179.728 | 167.213 | 173.652 | 161.136 | 174.893 | 162.377 | | 173.681 | 161.132 | 312.327 | 299.778 | 174.314 | 161.765 | 178.588 | 166.039 | 172.511 | 159.962 | 173.752 | 161.203 | | 172.533 | 159.952 | 311.179 | 298.598 | 173.166 | 160.584 | 177.44 | 164.859 | 171.363 | 158.782 | 172.604 | 160.023 | | 171.377 | 158.766 | 310.023 | 297.412 | 172.01 | 159.398 | 176.284 | 163.672 | 170.208 | 157.596 | 171.449 | 158.837 | | 170.215 | 157.574 | 308.861 | 296.22 | 170.847 | 158.206 | 175.121 | 162.481 | 169.045 | 156.404 | 170.286 | 157.645 | | 169.045 | 156.377 | 307.691 | 295.022 | 169.678 | 157.009 | 173.952 | 161.283 | 167.875 | 155.207 | 169.116 | 156.448 | | 167.868 | 155.174 | 306.514 | 293.82 | 168.501 | 155.807 | 172.775 | 160.081 | 166.698 | 154.004 | 167.94 | 155.246 | | 166.685 | 153.967 | 305.331 | 292.613 | 167.318 | 154.6 | 171.592 | 158.874 | 165.515 | 152.797 | 166.757 | 154.038 | | 165.496 | 152.756 | 304.142 | 291.401 | 166.129 | 153.388 | 170.403 | 157.662 | 164.326 | 151.586 | 165.567 | 152.827 | | 164.301 | 151.54 | 302.947 | 290.186 | 164.933 | 152.173 | 169.208 | 156.447 | 163.131 | 150.37 | 164.372 | 151.611 | | 163.1 | 150.321 | 301.746 | 288.967 | 163.733 | 150.953 | 168.007 | 155.227 | 161.93 | 149.151 | 163.171 | 150.392 | | 161.894 | 149.098 | 300.54 | 287.744 | 162.526 | 149.731 | 166.801 | 154.005 | 160.724 | 147.928 | 161.965 | 149.169 | | 160.683 | 147.873 | 299.329 | 286.518 | 161.315 | 148.505 | 165.589 | 152.779 | 159.513 | 146.703 | 160.754 | 147.944 | | 159.467 | 146.644 | 298.113 | 285.29 | 160.1 | 147.277 | 164.374 | 151.551 | 158.297 | 145.475 | 159.538 | 146.716 | | 158.247 | 145.414 | 296.893 | 284.06 | 158.88 | 146.047 | 163.154 | 150.321 | 157.077 | 144.244 | 158.318 | 145.486 | | 157.023 | 144.182 | 295.669 | 282.828 | 157.656 | 144.815 | 161.93 | 149.089 | 155.853 | 143.013 | 157.095 | 144.254 | | 155.796 | 142.949 | 294.442 | 281.595 | 156.429 | 143.582 | 160.703 | 147.856 | 154.626 | 141.779 | 155.867 | 143.021 | | 154.566 | 141.715 | 293.212 | 280.361 | 155.198 | 142.348 | 159.473 | 146.622 | 153.396 | 140.545 | 154.637 | 141.787 | | 153.333 | 140.481 | 291.979 | 279.127 | 153.965 | 141.113 | 158.24 | 145.388 | 152.163 | 139.311 | 153.404 | 140.552 | | 152.098 | 139.246 | 290.744 | 277.892 | 152.73 | 139.879 | 157.004 | 144.153 | 150.928 | 138.076 | 152.169 | 139.318 | | 150.861 | 138.012 | 289.507 | 276.658 | 151.493 | 138.645 | 155.768 | 142.919 | 149.691 | 136.842 | 150.932 | 138.084 | | 149.622 | 136.779 | 288.268 | 275.425 | 150.255 | 137.412 | 154.529 | 141.686 | 148.453 | 135.609 | 149.694 | 136.851 | | 148.383 | 135.547 | 287.029 | 274.193 | 149.016 | 136.18 | 153.29 | 140.454 | 147.213 | 134.377 | 148.455 | 135.619 | | 147.143 | 134.317 | 285.789 | 272.963 | 147.776 | 134.95 | 152.05 | 139.224 | 145.974 | 133.147 | 147.215 | 134.389 | | 145.904 | 133.089 | 284.55 | 271.735 | 146.536 | 133.722 | 150.811 | 137.996 | 144.734 | 131.919 | 145.975 | 133.161 | | 144.664 | 131.864 | 283.31 | 270.51 | 145.297 | 132.496 | 149.571 | 136.771 | 143.495 | 130.694 | 144.736 | 131.935 | | 143.426 | 130.641 | 282.072 | 269.287 | 144.059 | 131.274 | 148.333 | 135.548 | 142.256 | 129.472 | 143.497 | 130.713 | | 142.189 | 129.422 | 280.835 | 268.068 | 142.821 | 130.055 | 147.095 | 134.329 | 141.019 | 128.253 | 142.26 | 129.494 | | 140.953 | 128.207 | 279.599 | 266.853 | 141.586 | 128.84 | 145.86 | 133.114 | 139.783 | 127.037 | 141.025 | 128.278 | | 139.72 | 126.996 | 278.366 | 265.642 | 140.352 | 127.629 | 144.627 | 131.903 | 138.55 | 125.826 | 139.791 | 127.067 | | 138.489 | 125.789 | 277.135 | 264.435 | 139.122 | 126.422 | 143.396 | 130.696 | 137.319 | 124.619 | 138.56 | 125.861 | | 137.261 | 124.588 | 275.907 | 263.233 | 137.894 | 125.22 | 142.168 | 129.494 | 136.091 | 123.418 | 137.333 | 124.659 | | 136.037 | 123.391 | 274.683 | 262.037 | 136.669 | 124.024 | 140.944 | 128.298 | 134.867 | 122.221 | 136.108 | 123.462 | | 134.816 | 122.2 | 273.462 | 260.846 | 135.449 | 122.833 | 139.723 | 127.107 | 133.646 | 121.03 | 134.887 | 122.271 | | 133.599 | 121.015 | 272.245 | 259.661 | 134.232 | 121.647 | 138.506 | 125.922 | 132.43 | 119.845 | 133.671 | 121.086 | | 132.387 | 119.836 | 271.033 | 258.482 | 133.02 | 120.468 | 137.294 | 124.742 | 131.218 | 118.666 | 132.459 | 119.907 | | 131.18 | 118.663 | 269.826 | 257.309 | 131.813 | 119.296 | 136.087 | 123.57 | 130.01 | 117.493 | 131.252 | 118.734 | | 129.978 | 117.497 | 268.624 | 256.143 | 130.611 | 118.13 | 134.885 | 122.404 | 128.808 | 116.327 | 130.05 | 117.568 | | 128.782 | 116.338 | 267.428 | 254.984 | 129.414 | 116.971 | 133.689 | 121.245 | 127.612 | 115.168 | 128.853 | 116.409 | | 127.591 | 115.186 | 266.237 | 253.832 | 128.224 | 115.819 | 132.498 | 120.093 | 126.421 | 114.016 | 127.663 | 115.257 | | 126.407 | 114.041 | 265.053 | 252.687 | 127.039 | 114.674 | 131.314 | 118.948 | 125.237 | 112.872 | 126.478 | 114.113 | | 125.229 | 112.904 | 263.875 | 251.55 | 125.861 | 113.537 | 130.136 | 117.811 | 124.059 | 111.735 | 125.3 | 112.976 | | 124.057 | 111.775 | 262.703 | 250.421 | 124.69 | 112.408 | 128.964 | 116.682 | 122.887 | 110.605 | 124.129 | 111.846 | | 122.893 | 110.654 | 261.539 | 249.299 | 123.525 | 111.286 | 127.8 | 115.56 | 121.723 | 109.484 | 122.964 | 110.725 | | 121.735 | 109.54 | 260.381 | 248.186 | 122.368 | 110.173 | 126.642 | 114.447 | 120.565 | 108.37 | 121.807 | 109.611 | | 120.585 | 108.435 | 259.231 | 247.081 | 121.218 | 109.067 | 125.492 | 113.341 | 119.415 | 107.265 | 120.657 | 108.506 | | 119.443 | 107.337 | 258.089 | 245.983 | 120.075 | 107.97 | 124.349 | 112.244 | 118.273 | 106.167 | 119.514 | 107.409 | | 118.308 | 106.248 | 256.954 | 244.894 | 118.94 | 106.881 | 123.214 | 111.155 | 117.138 | 105.079 | 118.379 | 106.32 | | 117.18 | 105.168 | 255.826 | 243.814 | 117.813 | 105.8 | 122.087 | 110.074 | 116.011 | 103.998 | 117.252 | 105.239 | | 116.061 | 104.095 | 254.707 | 242.741 | 116.694 | 104.728 | 120.968 | 109.002 | 114.891 | 102.926 | 116.133 | 104.167 | | 114.95 | 103.031 | 253.596 | 241.677 | 115.583 | 103.664 | 119.857 | 107.938 | 113.78 | 101.862 | 115.021 | 103.103 | | 113.847 | 101.976 | 252.493 | 240.622 | 114.479 | 102.609 | 118.754 | 106.883 | 112.677 | 100.806 | 113.918 | 102.047 | | 112.752 | 100.929 | 251.398 | 239.575 | 113.384 | 101.561 | 117.659 | 105.836 | 111.582 | 99.759 | 112.823 | 101 | | 111.665 | 99.8901 | 250.311 | 238.536 | 112.298 | 100.523 | 116.572 | 104.797 | 110.495 | 98.7202 | 111.736 | 99.9614 | | 110.587 | 98.8596 | 249.233 | 237.506 | 111.219 | 99.4923 | 115.493 | 103.766 | 109.417 | 97.6898 | 110.658 | 98.931 | | 109.517 | 97.8375 | 248.162 | 236.483 | 110.149 | 98.4702 | 114.423 | 102.744 | 108.347 | 96.6677 | 109.588 | 97.9089 | | 108.455 | 96.8237 | 247.101 | 235.47 | 109.087 | 97.4563 | 113.362 | 101.73 | 107.285 | 95.6538 | 108.526 | 96.895 | | 107.401 | 95.818 | 246.047 | 234.464 | 108.034 | 96.4506 | 112.308 | 100.725 | 106.231 | 94.6481 | 107.473 | 95.8893 | | 106.356 | 94.8203 | 245.002 | 233.466 | 106.989 | 95.453 | 111.263 | 99.7271 | 105.186 | 93.6505 | 106.427 | 94.8917 | | 105.319 | 93.8307 | 243.965 | 232.477 | 105.952 | 94.4633 | 110.226 | 98.7375 | 104.149 | 92.6609 | 105.39 | 93.9021 | | 104.29 | 92.849 | 242.936 | 231.495 | 104.923 | 93.4816 | 109.197 | 97.7558 | 103.121 | 91.6791 | 104.362 | 92.9203 | | 103.27 | 91.875 | 241.916 | 230.521 | 103.902 | 92.5077 | 108.177 | 96.7818 | 102.1 | 90.7052 | 103.341 | 91.9464 | | 102.257 | 90.9087 | 240.903 | 229.555 | 102.89 | 91.5414 | 107.164 | 95.8155 | 101.088 | 89.7389 | 102.329 | 90.9801 | | 101.253 | 89.95 | 239.899 | 228.596 | 101.886 | 90.5826 | 106.16 | 94.8568 | 100.083 | 88.7801 | 101.324 | 90.0213 | | 100.257 | 88.9986 | 238.902 | 227.645 | 100.889 | 89.6313 | 105.163 | 93.9054 | 99.0867 | 87.8288 | 100.328 | 89.07 | | 99.2679 | 88.0545 | 237.914 | 226.7 | 99.9005 | 88.6872 | 104.175 | 92.9614 | 98.098 | 86.8847 | 99.3392 | 88.1259 | | 98.287 | 87.1176 | 236.933 | 225.763 | 98.9196 | 87.7502 | 103.194 | 92.0244 | 97.1171 | 85.9477 | 98.3583 | 87.1889 | | 97.3137 | 86.1876 | 235.96 | 224.833 | 97.9463 | 86.8202 | 102.22 | 91.0944 | 96.1438 | 85.0177 | 97.385 | 86.2589 | | 96.3479 | 85.2644 | 234.994 | 223.91 | 96.9805 | 85.897 | 101.255 | 90.1712 | 95.1781 | 84.0945 | 96.4193 | 85.3357 | | 95.3895 | 84.3478 | 234.035 | 222.994 | 96.0222 | 84.9804 | 100.296 | 89.2546 | 94.2197 | 83.178 | 95.4609 | 84.4192 | | 94.4384 | 83.4377 | 233.084 | 222.084 | 95.071 | 84.0704 | 99.3452 | 88.3445 | 93.2686 | 82.2679 | 94.5098 | 83.5091 | | 93.4944 | 82.534 | 232.14 | 221.18 | 94.127 | 83.1666 | 98.4012 | 87.4408 | 92.3246 | 81.3641 | 93.5658 | 82.6053 | | 92.5574 | 81.6363 | 231.203 | 220.282 | 93.19 | 82.269 | 97.4642 | 86.5432 | 91.3875 | 80.4665 | 92.6287 | 81.7077 | | 91.6272 | 80.7447 | 230.273 | 219.391 | 92.2598 | 81.3773 | 96.534 | 85.6515 | 90.4573 | 79.5748 | 91.6986 | 80.816 | | 90.7037 | 79.8588 | 229.35 | 218.505 | 91.3363 | 80.4914 | 95.6105 | 84.7656 | 89.5338 | 78.689 | 90.775 | 79.9302 | | 89.7867 | 78.9786 | 228.433 | 217.624 | 90.4193 | 79.6112 | 94.6935 | 83.8854 | 88.6168 | 77.8087 | 89.8581 | 79.0499 | | 88.8761 | 78.1037 | 227.522 | 216.75 | 89.5087 | 78.7364 | 93.7829 | 83.0105 | 87.7062 | 76.9339 | 88.9474 | 78.1751 | | 87.9717 | 77.2342 | 226.618 | 215.88 | 88.6043 | 77.8668 | 92.8785 | 82.141 | 86.8018 | 76.0643 | 88.043 | 77.3055 | | 87.0733 | 76.3696 | 225.719 | 215.016 | 87.7059 | 77.0023 | 91.9801 | 81.2764 | 85.9034 | 75.1998 | 87.1446 | 76.441 | | 86.1808 | 75.51 | 224.827 | 214.156 | 86.8134 | 76.1426 | 91.0876 | 80.4168 | 85.0109 | 74.3401 | 86.2522 | 75.5813 | | 85.294 | 74.655 | 223.94 | 213.301 | 85.9266 | 75.2876 | 90.2008 | 79.5618 | 84.1242 | 73.4852 | 85.3654 | 74.7264 | | 84.4127 | 73.8046 | 223.059 | 212.45 | 85.0454 | 74.4372 | 89.3195 | 78.7114 | 83.2429 | 72.6347 | 84.4841 | 73.8759 | | 83.5368 | 72.9584 | 222.183 | 211.604 | 84.1695 | 73.591 | 88.4436 | 77.8652 | 82.367 | 71.7886 | 83.6082 | 73.0298 | | 82.6661 | 72.1164 | 221.312 | 210.762 | 83.2987 | 72.749 | 87.5729 | 77.0232 | 81.4963 | 70.9465 | 82.7375 | 72.1877 | | 81.8004 | 71.2783 | 220.446 | 209.924 | 82.433 | 71.9109 | 86.7072 | 76.1851 | 80.6305 | 70.1084 | 81.8718 | 71.3496 | | 80.9395 | 70.4439 | 219.585 | 209.09 | 81.5721 | 71.0766 | 85.8463 | 75.3507 | 79.7697 | 69.2741 | 81.0109 | 70.5153 | | 80.0833 | 69.6131 | 218.729 | 208.259 | 80.7159 | 70.2458 | 84.9901 | 74.5199 | 78.9134 | 68.4433 | 80.1546 | 69.6845 | | 79.2315 | 68.7857 | 217.877 | 207.432 | 79.8641 | 69.4183 | 84.1383 | 73.6925 | 78.0617 | 67.6159 | 79.3029 | 68.8571 | | 78.3841 | 67.9615 | 217.03 | 206.607 | 79.0167 | 68.5941 | 83.2909 | 72.8683 | 77.2142 | 66.7916 | 78.4554 | 68.0328 | | 77.5407 | 67.1402 | 216.187 | 205.786 | 78.1733 | 67.7728 | 82.4475 | 72.047 | 76.3708 | 65.9704 | 77.612 | 67.2116 | | 76.7013 | 66.3217 | 215.347 | 204.968 | 77.3339 | 66.9544 | 81.6081 | 71.2286 | 75.5314 | 65.1519 | 76.7726 | 66.3931 | | 75.8656 | 65.5059 | 214.512 | 204.152 | 76.4982 | 66.1385 | 80.7724 | 70.4127 | 74.6957 | 64.3361 | 75.9369 | 65.5773 | | 75.0335 | 64.6925 | 213.679 | 203.338 | 75.6661 | 65.3251 | 79.9403 | 69.5993 | 73.8636 | 63.5226 | 75.1048 | 64.7638 | | 74.2047 | 63.8813 | 212.851 | 202.527 | 74.8374 | 64.5139 | 79.1115 | 68.7881 | 73.0349 | 62.7114 | 74.2761 | 63.9526 | | 73.3792 | 63.0721 | 212.025 | 201.718 | 74.0118 | 63.7048 | 78.286 | 67.9789 | 72.2093 | 61.9023 | 73.4505 | 63.1435 | | 72.5567 | 62.2649 | 211.203 | 200.911 | 73.1893 | 62.8975 | 77.4635 | 67.1717 | 71.3868 | 61.095 | 72.628 | 62.3362 | | 71.737 | 61.4592 | 210.383 | 200.105 | 72.3696 | 62.0919 | 76.6438 | 66.366 | 70.5671 | 60.2894 | 71.8083 | 61.5306 | | 70.9199 | 60.6551 | 209.566 | 199.301 | 71.5525 | 61.2877 | 75.8267 | 65.5619 | 69.7501 | 59.4853 | 70.9913 | 60.7265 | | 70.1053 | 59.8523 | 208.751 | 198.498 | 70.738 | 60.4849 | 75.0121 | 64.7591 | 68.9355 | 58.6824 | 70.1767 | 59.9236 | | 69.293 | 59.0505 | 207.939 | 197.696 | 69.9257 | 59.6832 | 74.1998 | 63.9574 | 68.1232 | 57.8807 | 69.3644 | 59.1219 | | 68.4828 | 58.2497 | 207.129 | 196.896 | 69.1155 | 58.8824 | 73.3896 | 63.1565 | 67.313 | 57.0799 | 68.5542 | 58.3211 | | 67.6745 | 57.4497 | 206.32 | 196.096 | 68.3072 | 58.0823 | 72.5813 | 62.3565 | 66.5047 | 56.2798 | 67.7459 | 57.521 | | 66.868 | 56.6502 | 205.514 | 195.296 | 67.5006 | 57.2828 | 71.7748 | 61.557 | 65.6981 | 55.4803 | 66.9393 | 56.7215 | | 66.0629 | 55.851 | 204.709 | 194.497 | 66.6956 | 56.4836 | 70.9697 | 60.7578 | 64.8931 | 54.6812 | 66.1343 | 55.9224 | | 65.2593 | 55.0521 | 203.905 | 193.698 | 65.8919 | 55.6847 | 70.1661 | 59.9589 | 64.0894 | 53.8822 | 65.3306 | 55.1234 | | 64.4568 | 54.2531 | 203.103 | 192.899 | 65.0894 | 54.8857 | 69.3636 | 59.1599 | 63.2869 | 53.0832 | 64.5281 | 54.3244 | | 63.6553 | 53.4539 | 202.301 | 192.1 | 64.2879 | 54.0866 | 68.5621 | 58.3607 | 62.4854 | 52.2841 | 63.7266 | 53.5253 | | 62.8545 | 52.6544 | 201.5 | 191.3 | 63.4872 | 53.287 | 67.7614 | 57.5612 | 61.6847 | 51.4846 | 62.9259 | 52.7258 | | 62.0545 | 51.8543 | 200.7 | 190.5 | 62.6871 | 52.4869 | 66.9613 | 56.7611 | 60.8846 | 50.6845 | 62.1258 | 51.9257 | | 61.2548 | 51.0535 | 199.901 | 189.699 | 61.8874 | 51.6861 | 66.1616 | 55.9603 | 60.085 | 49.8836 | 61.3262 | 51.1248 | | 60.4554 | 50.2517 | 199.101 | 188.898 | 61.088 | 50.8843 | 65.3622 | 55.1585 | 59.2856 | 49.0819 | 60.5268 | 50.3231 | | 59.6561 | 49.4488 | 198.302 | 188.095 | 60.2887 | 50.0815 | 64.5629 | 54.3556 | 58.4862 | 48.279 | 59.7274 | 49.5202 | | 58.6813 | 48.8199 | 197.327 | 187.466 | 59.314 | 49.4525 | 63.5881 | 53.7267 | 57.5115 | 47.6501 | 58.7527 | 48.8913 | | 57.4945 | 48.4013 | 196.14 | 187.047 | 58.1271 | 49.034 | 62.4013 | 53.3081 | 56.3246 | 47.2315 | 57.5658 | 48.4727 | | 56.3074 | 47.9809 | 194.953 | 186.627 | 56.94 | 48.6135 | 61.2142 | 52.8877 | 55.1375 | 46.811 | 56.3787 | 48.0522 | | 55.1197 | 47.5584 | 193.766 | 186.204 | 55.7523 | 48.191 | 60.0265 | 52.4652 | 53.9498 | 46.3886 | 55.191 | 47.6298 | [ ... Additional output not shown ... ]
Example plots from GTVT
By default, a plot showing 6 panels (one for each instrument, the FGS, and the observatory V3PA) will be displayed by GTVT on the screen or sent to a named output file. The y-axis of each plot shows valid aperture PAs for each instrument as a function of time. These values can be entered into the relevant APT special requirements as needed for a given science case.
Figure 1. The default 6-panel GTVT output plot
Click on the figure for a larger view.
Note that over time, a large range of potential position angles are available for this target, which is at an ecliptic latitude of ~24.3°, and the pattern repeats closely from one year to the next.
This summary plot may not be that useful when saved as a file. But in interactive mode, icons at the lower left of the plot window allow you to pan and zoom within each panel for a closer look at the figures. After panning and zooming in the interactive plot, the right-most icon provides another way to save the current view of the interactive plot.
Alternatively, for viewing a single instrument, use the --instrument argument to specify a particular instrument; this produces a display with a single panel plot for that instrument. Also, the time range on the default plot covers the entire current period with a preliminary orbital ephemeris. You can also use the --start_date and --end_date arguments to shorten the time range that is plotted. Figure 2 shows an example made with the following command:
jwst_gtvt --ra=325.678 --dec=43.586 --target_name "SS Cyg" --instrument nirspec --start_date 2022-07-01 --end_date 2023-01-31
Figure 2. A GTVT plot for a single instrument and a restricted time range
This target is at an ecliptic latitude of ~24.3° and has a single, long visibility period between the chosen dates. A wide range of position angles are available for such a target. The vertical bar denotes a change around the 0° boundary.
Additional information on JWST’s pointing restrictions, and how they affect target visibility and available position angles, is included in the article JWST Position Angles, Ranges, and Offsets.