1-arc_file 2Specify an arc file to be plotted against the background stars. Each 3line in the file must have the following syntax: 4 5dec1 ra1 dec2 ra2 6 7where declination is in degrees and right ascension is in hours. This 8option has no effect if -projection is specified. 9 10-arc_spacing spacing 11When drawing an arc, draw line segments that are spacing degrees 12apart. The default is 0.1 degrees. Line segments shorter than 13spacing will not be drawn. 14 15-arc_thickness thickness 16Specify the thickness of arcs. The default is 1 pixel. When drawing 17arcs on a planet using the arc_file option in the configuration file, 18use the arc_thickness option there too. 19 20-background background_file 21Use background_file as the background image, with the planet to be 22superimposed upon it. A color may also be supplied (e.g. -background 23"navy blue" or -background 0xff00ff). 24 25-base_magnitude magnitude 26A star of the specified magnitude will have a pixel brightness of 1. 27The default value is 10. Stars will be drawn more brightly if this 28number is larger. 29 30-body body 31Render an image of the specified planet or satellite. Valid values 32for body are sun, mercury, venus, earth, moon, mars, phobos, deimos, 33jupiter, io, europa, ganymede, callisto, saturn, mimas, enceladus, 34tethys, dione, rhea, titan, hyperion, iapetus, phoebe, uranus, 35miranda, ariel, umbriel, titania, oberon, neptune, triton, nereid, 36pluto, charon, random, and major. 37 38The field of view can also be centered on a satellite location using 39"naif" or "norad", along with the satellite id. For example, "-body 40naif-82" will center the field of view on NAIF ID -82, which is the 41Cassini orbiter. Xplanet must be compiled with SPICE support and the 42required kernels must be present. See the README in the spice 43subdirectory for more details. Using "-body norad20580" will center 44the field of view on NORAD ID 20580, which is the Hubble Space 45Telescope. The appropriate TLE files must be present in this case. 46See the README in the satellites subdirectory for more information. 47 48Using "path" will center the field of view on the direction of motion 49of the origin. This direction is relative to the direction of motion 50of the body specified by -path_relative_to. 51 52Earth is the default body. This option is the same as -target. 53 54-center +x+y 55Place the center of the rendered body at pixel coordinates (x, y). 56The upper left corner of the screen is at (0,0). Either x or y may be 57negative. The default value is the center of the screen. 58 59-color color 60Set the color for the label. The default is "red". Any color in the 61rgb.txt file may be used. Colors may also be specified by RGB hex 62values; for example -color 0xff and -color blue mean the same thing, 63as do -color 0xff0000 and -color red. 64 65-config config_file 66Use the configuration file config_file. The format of config_file is 67described in README.config. See the description of -searchdir to see 68where xplanet looks in order to find the configuration file. 69 70-create_scattering_tables scattering_file 71Create lookup tables for Rayleigh scattering. See the README in the 72scattering directory for more information. 73 74-date YYYYMMDD.HHMMSS 75Use the date specified instead of the current local time. The date is 76assumed to be GMT. 77 78-date_format string 79Specify the format for the date/time label. This format string is 80passed to strftime(3). The default is "%c %Z", which shows the date, 81time, and time zone in the locale's appropriate date and time 82representation. 83 84-dynamic_origin file 85Specify an observer location. The location is relative to the body 86specified with -origin (by default, this is the Sun). The last line 87of the file must be of the form 88YYYYMMDD.HHMMSS range lat lon localtime 89For example, 9019951207.120000 10.328 -3.018 97.709 9.595 91The specified time is ignored and the current time is used. The range 92is in planetary radii, and lat and lon are in degrees. Localtime (in 93hours) is optional, but if present, it will be used in place of the 94longitude. Only the last line of the file is used. This file may be 95updated between renderings using a script executed with the 96-prev_command or -post_command options. 97 98-ephemeris_file filename 99Specify a JPL digital ephemeris file (DE200, DE405, or DE406) to use 100for computing planetary positions. Xplanet uses Bill Gray's code 101(http://www.projectpluto.com/jpl_eph.htm), which reads both big and 102little endian binary files. The ephemeris files found at 103ftp://ssd.jpl.nasa.gov/pub/eph/export/unix are big endian files, but 104you do not need to do any additional byte-swapping to use them. See 105the description of -searchdir to see where xplanet looks in order to 106find the ephemeris file. 107 108-font fontname 109Set the font for the label. Only TrueType fonts are supported. If 110the -pango option is used, fontname is taken to be the font family 111name (e.g. "Arial"). 112 113-fontsize size 114Specify the point size. The default is 12. 115 116-fork 117Detach from the controlling terminal. This is useful on MS Windows to 118run xplanet from a batch file without having to keep a DOS window 119open. Be careful when using this option; it's easy to have multiple 120processes running at the same time without knowing it - check the Task 121Manager. On unix systems this is pretty much the same as running 122xplanet in the background. 123 124-fov 125Specify the field of view, in degrees. This option and the -radius 126option are mutually exclusive. This option has no effect if the 127-projection option is used. 128 129-geometry string 130Specify the image geometry using the standard X window geometry 131syntax, [<width>{xX}<height>][{+-}<xoffset>{+-}<yoffset>] 132(e.g. 256x256-10+10 puts a window 256x256 pixels in size 10 pixels 133away from the right side and 10 pixels below the top of the root 134window). The root window outside of the image will be black. This 135option may be used with -window or -output. 136 137-glare radius 138Draw a glare around the sun with with a radius of the specified value 139larger than the sun. The default value is 28. 140 141-gmtlabel 142Same as the -label option, but show GMT instead of local time. 143 144-grs_longitude lon 145The longitude of Jupiter's Great Red Spot (GRS). A typical value is 14694 degrees. If this option is specified, longitudes on Jupiter will 147be calculated in System II coordinates. By default, longitudes are 148calculated in System III coordinates. When using this option, use an 149image map for Jupiter where the center of the GRS is at the pixel 0 150column, or the left side of the image. 151 152-hibernate seconds 153After the screen has been idle for the specified number of seconds, 154xplanet will sleep. This option requires xplanet to have been 155compiled with the X Screensaver extension. 156 157-idlewait seconds 158Don't run Xplanet unless the screen has been idle for the specified 159number of seconds. This option requires xplanet to have been compiled 160with the X Screensaver extension. 161 162-interpolate_origin_file 163This option is only useful in conjunction with -origin_file. It 164computes the observer position at the current time by interpolating 165between values specified in the origin file. This is useful if you 166have spacecraft positions tabulated in an origin file, but want a real 167time view. 168 169-jdate Julian date 170Use the specified Julian date instead of the current local time. 171 172-label 173Display a label in the upper right corner. 174 175-labelpos 176Specify the location of the label using the standard X window geometry 177syntax. The default position is "-15+15", or 15 pixels to the left 178and below the top right corner of the display. This option implies 179-label. 180 181-label_altitude 182Display the altitude above the surface instead of distance from the 183body center in the label. 184 185-label_body body 186Use the specified body to calculate the sub-observer, sub-solar, and 187illumination values in the label. This is useful with the -separation 188option. 189 190-label_string 191Specify the text of the first line of the label. By default, it says 192something like "Looking at Earth". Any instances of %t will be 193replaced by the target name, and any instances of %o will be replaced 194by the origin name. 195 196-latitude latitude 197Render the target body as seen from above the specified latitude (in 198degrees). The default value is 0. 199 200-light_time 201Account for the time it takes for light to travel from the target body 202to the observer. The default is to ignore the effects of light time. 203 204-localtime localtime 205Place the observer above the longitude where the local time is the 206specified value. 0 is midnight and 12 is noon. 207 208-log_magstep step 209Increase the brightness of a star by 10^step for each integer decrease 210in magnitude. The default value is 0.4. This means that a star of 211magnitude 2 is 10^0.4 (about 2.5) times brighter than a star of 212magnitude 3. A larger number makes stars brighter. 213 214-longitude longitude 215Place the observer above the specified longitude (in degrees). 216Longitude is positive going east, negative going west (for the earth 217and moon), so for example Los Angeles is at -118 or 242. The default 218value is 0. 219 220-make_cloud_maps 221If there is an entry in the config file for cloud_map, xplanet will 222output a day and night image with clouds overlaid and then exit. The 223images will be created in the directory specified by -tmpdir, or in 224the current directory if -tmpdir is not used. The names of the output 225images default to day_clouds.jpg and night_clouds.jpg, but may be 226changed by the -output option. If "-output filename.extension" is 227specified, the output images will be named "day_filename.extension" 228and "night_filename.extension". The dimensions of the output images 229are the same as the day image. 230 231-marker_file 232Specify a file containing user defined marker data to display against 233the background stars. The format of each line is generally 234declination, right ascension, string, as in the example below: 235 236-16.7161 6.7525 "Sirius" 237 238For additional options which may be specified, see the marker_file 239entry in README.config. This option has no effect if -projection is 240specified. This option is not meant for city markers; for that use 241the marker_file option in the configuration file. 242 243-markerbounds filename 244Write coordinates of the bounding box for each marker to filename. 245This might be useful if you're using xplanet to make imagemaps for web 246pages. Each line looks like: 247 248204,312 277,324 Los Angeles 249 250where the coordinates are for the upper left and lower right corners 251of the box. This file gets rewritten every time xplanet renders its 252image. 253 254-north north_type 255This option rotates the image so that the top points to north_type. 256Valid values for north_type are: 257 258body: body's north pole 259galactic: galactic north pole 260orbit: body's orbital north pole (perpendicular to the orbit plane) 261path: origin's velocity vector (also see -path_relative_to option) 262separation: perpendicular to the line of sight and the 263 target-separation target line (see -separation option) 264 265The default value is "body". 266 267-num_times num_times 268Run num_times before exiting. The default is to run indefinitely. 269 270-origin body 271Place the observer at the center of the specified body. Valid values 272are the same as for -target. In addition, "above", "below", or 273"system" may be specified. Using "above" or "below" centers the view 274on the body's primary and the field of view is large enough to show 275the body's orbit. Using "system" places the observer at the center of 276a random body in the same system as the target body. Two bodies are 277in the same system if one of the following is true: 278 279 1) target and origin have same primary 280 2) target is origin's primary 281 3) origin is target's primary 282 283If the body name is preceded by a dash, the observer is placed on the 284opposite side of the target from the specified body at a distance 285equal to the distance between the target and body. For example, 286-target earth -origin sun places the observer at the center of the 287sun. If -target earth -origin -sun is used, the observer is placed on 288a line connecting the centers of the earth and sun at a distance of 1 289AU farther from the sun than the earth. 290 291-origin_file origin_file 292Specify a list of observer positions in origin_file. The positions 293are relative to the body specified with -origin (by default, this is 294the Sun). Each line should be of the form 295YYYYMMDD.HHMMSS range lat lon localtime 296For example, 29719951207.120000 10.328 -3.018 97.709 9.595 298Range is in planetary radii, and lat and lon are in degrees. The date 299is the only required value. If the localtime (in hours) is supplied, 300it will be used in place of the longitude. For each line in the 301origin file, the observer is placed at the specified position, 302relative to the body specified with -origin. This option is useful 303for showing spacecraft flybys or orbiting around a planet. Any line 304with a # in the first column is ignored. 305 306-output filename 307Output to a file instead of rendering to a window. The file format is 308taken from the extension. Currently .gif, .jpg, .ppm, .png, and .tiff 309images can be created, if xplanet has been compiled with the 310appropriate libraries. The image size defaults to 512 by 512 pixels 311but this may be changed by the -geometry flag. If used with the 312-num_times option, each output file will be numbered sequentially. 313 314-output_map filename 315Output the intermediate rectangular map that is created in the process 316of rendering the final image. It will have the same dimensions as the 317default day map. 318 319-output_start_index index 320Start numbering output files at index. The default is 0. 321 322-pango 323Use the Pango (http://www.pango.org) library for rendering 324internationalized text. Pango uses Unicode for all of its encoding, 325and will eventually support output in all the worlds major languages. 326If xplanet has not been compiled with this library this option will be 327ignored. There appear to be memory leaks in the pango library, so I 328don't recommend letting xplanet run indefinitely with this option. 329 330-path_relative_to body 331Only used with -north path or -target path. The origin's velocity 332vector is calculated relative to the specified body. By default, this 333is the Sun. 334 335-post_command command 336-prev_command command 337Run command either before or after each time xplanet renders an image. 338On MS Windows, you may need to use unix-style paths. For example: 339xplanet.exe -prev_command ./prev.bat 340 341-print_ephemeris 342Print the heliocentric rectangular equatorial coordinates (J2000) for 343each body xplanet knows about, and then exit. 344 345-projection projection_type 346The projection type may be one of ancient, azimuthal, bonne, 347equal_area, gnomonic, hemisphere, icosagnomonic, lambert, mercator, 348mollweide, orthographic, peters, polyconic, rectangular, or tsc. The 349default is no projection. Multiple bodies will not be shown if this 350option is specified, although shadows will still be drawn. 351 352-proj_param value 353Pass additional parameters for some projections. The only projections 354that use this option at present are the Bonne, Gnomonic, and Mercator 355projections. The Bonne projection is conformal at the specified 356latitude. Higher values lead to a thinner heart shape. The default 357is 50 degrees. The Gnomonic and Mercator projections use the 358specified latitude as the boundaries of the projection. The defaults 359are 45 and 80 degrees, respectively. This option may be used more 360than once for future projections that require additional parameters. 361Only the first value is used at present. 362 363-quality quality 364This option is only used when creating JPEG images. The quality can 365range from 0 to 100. The default value is 80. 366 367-radius radius 368Specify the radius of the globe as a percent of the screen height. 369The default value is 45% of the screen height. When drawing Saturn, 370the radius value applies to the radius of the outer ring. 371 372-random 373Place the observer above a random latitude and longitude. 374 375-range range 376Render the globe as seen from a distance of range from the planet's 377center, in units of the planetary radius. The default value is 1000. 378Note that if you use very close ranges the field of view of the screen 379can be greater than 180 degrees! If you want an "up close" image use 380the -radius option. 381 382-rotate angle 383Rotate the globe by angle degrees counterclockwise so that north (as 384defined by the -north argument) isn't at the top. The default value 385is 0. My friends in the Southern Hemisphere can use -rotate 180 to 386make the earth look like it should! For non-orthographic projections, 387the globe is rotated and then projected, if that helps you visualize 388what to expect. 389 390-save_desktop_file 391On Microsoft Windows and Mac OS X, xplanet creates an intermediate 392image file which is used to set the desktop. This file will be 393created in the -tmpdir directory. By default, this image is removed 394after the desktop has been set. Specifying this option will leave the 395file in place. 396 397-searchdir directory 398Any files used by xplanet should be placed in one of the following 399directories depending on its type: "arcs", "config", "ephemeris", 400"fonts", "images", "markers", "origin", "satellites", or "stars". By 401default, xplanet will look for a file in the following order: 402The current directory 403searchdir 404subdirectories of searchdir 405subdirectories of xplanet (if it exists in the current directory) 406subdirectories of ${HOME}/.xplanet on X11 407subdirectories of ${HOME}/Library/Xplanet on Mac OS X 408subdirectories of DATADIR/xplanet 409DATADIR is set at compile time and defaults to /usr/local/share. 410 411-separation body:dist 412Place the observer at a location where the target body and the 413separation body are dist degrees apart. For example "-target earth 414-separation moon:-3" means place the observer at a location where the 415moon appears 3 degrees to the left of the earth. 416 417-spice_ephemeris index 418Use SPICE kernels to compute the position of the named body. The 419index is the naif ID code (e.g. 599 for Jupiter). The -spice_file 420option must be used to supply the names of the kernel files. This 421option may be used more than once for different bodies. 422 423-spice_file spice_file 424Specify a file containing a list of objects to display. A file 425containing a list of SPICE kernels to read named spice_file.krn must exist 426along with spice_file. See the README in the "spice" subdirectory for 427more information. 428 429-starfreq frequency 430Fraction of background pixels that will be colored white. The default 431value is 0.001. This option is only meaningful with the azimuthal, 432mollweide, orthographic, and peters projections. 433 434-starmap starmap 435Use starmap to draw the background stars. This file should be a text 436file where each line has the following format: 437Declination, Right Ascension, Magnitude 438where Declination is in decimal degrees and Right Ascension is in 439decimal hours. For example, the entry for Sirius is 440-16.7161 6.7525 -1.46 441See the description of -searchdir to see where xplanet looks in order 442to find the star map. 443 444-target target 445Same as -body. 446 447-tt 448Use terrestrial time instead of universal time. The two differ 449slightly due to the non-uniform rotation of the earth. The default is 450to use universal time. 451 452-timewarp 453As in xearth, scale the apparent rate at which time progresses by 454factor. The default is 1. 455 456-tmpdir tmpdir 457Specify a directory that xplanet will use to place images created 458using -make_cloud_maps. On Microsoft Windows, xplanet will write 459a bitmap file called xplanet.bmp to the specified directory. The 460default is the result of the GetWindowsDirectory call (C:\WINDOWS on 461Win95). On Mac OS X, xplanet will create an intermediate PNG file in 462order to set the background. The default value is /tmp. On Windows 463and Mac OS X, the intermediate file will be removed unless the 464-save_desktop_file option is specified. 465 466-transparency 467Update the background pixmap for transparent Eterms and aterms. This 468option only works under X11. 469 470-transpng filename 471Same as the -output option, except set the background to be 472transparent when writing a PNG file. 473 474-utclabel 475Same as -gmtlabel. 476 477-verbosity level 478level output 479< 0 only fatal error messages 4800 non-fatal warning messages 4811 basic information 4822 basic diagnostics 4833 more detailed diagnostics 4844 very detailed diagnostics 485The default value is 0. 486 487-version 488Display current version information, along with a list of compile-time 489options that xplanet supports. 490 491-vroot 492Render the image to the virtual root window. Some window managers use 493one big window that sits over the real root window as their background 494window. Xscreensaver uses a virtual root window to cover the screen 495as well. 496 497-wait wait 498Update every wait seconds. 499 500-window 501Render the image to its own X window. The size defaults to 512 by 512 502pixels but this may be set by the -geometry flag. 503 504-window-id ID 505When using the X11 windowing system, draw to the window with the 506specified ID. 507 508-window_title title 509Set the window's title to title. This option implies -window. 510 511-XID ID 512Same as -window-id. 513 514-xscreensaver 515Same as -vroot. 516
