Ephemerides plug-in
Attachment:
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INSTALLATION (lua_plugins only):
- Remove all previous version of ephemerides if any.
- Unzip the pack inside the main Celestia's root. A new folder named "ephemerides" will be created under the "..celestia/extras/" folder containing all the files. Such folder can be moved also like subfolder of "../extras/lua_plugins/" path without affects its functionality. For the insertion within the lua_plugins see the "readme.txt".
INTERFACE:
The ephemerides bar, which caption moves on screen, shows four buttons. These buttons will be active as long as the observer is within a range of ten time the Earth's radius, otherwise all buttons will be deactivated. Ephemerides infos are thought to be shown only when the observer is near the Earth and not far away, being all infos now referred to Earth and no longer to the observer everywhere he is within the Solar System like was in the previous version. Each button, aside the button 4), performs a synchronous operation for the Earth and the observer. This synchronous Earth operation will not affect the reference frame for other objects whether the observer decides to fly elsewhere, being the plugin inactive beyond such Earth's radii distance, showing just the greyed-out buttons. However, one can always press the "f" key (follow) if he wish; but in such case the infos can varying as long as the Earth is rotating about its axis.
USAGE:
In the order, from left to right:
(button 1): a "goto home" button. Such button moves the observer perpendicular on an user-defined location at the default Celestia distance of 5 * earth's radius. The location's name and its coordinates are customizable through "ephemCfg.lua" file. The name of the location can be whatever, and will be displayed close to the pointer, even though the locaton is not set like .SSC location. This button is like an "utility" to aid the user in find its "return to home" operation after having played with ephemerides for other locations on Earth. The distance and the return delay are customizables too. Note that for distance > 10 the plugin will be inactive. Default distance = 5.0; default delay = 5.0, the default Celestia's distance and gotolonglat smooth moving. Click/unclick = move to home/hide the pointer.
button 2) Physical ephemerides button. It will show several physical ephemerides for all Celestia's objects. For deepsky objects and fictionals (diffuse), just their subEarth points will be displayed. Click/unclick = show/hide infos and pointer.
button 3) Visual ephemerides and rise/set times for all Celestia's object, deepsky, fictionals and spacecrafts objects too.
The rise/set times are referred to the ground perpendicular to the observer's orbit and to stay in orbit or at ground is the same for what concern the rise/set azimuths. The only difference is that at the ground will be displayed also the real time azimuths and altitudes measurements of the selected objects. Click/unclick = show/hide infos and pointer.
button 4) Color roulette button. It change the ephemerides color for text and pointer in pseudo-random manner. All colors will be randomized but the color-sequence will be same all the time. Useful for visual purposes. The random color can be printable on a txt file for helping to find a favorite main color settable through "ephemCfg.lua" file. The main color is now set like the default Celestia's HUD color. Random colors and main color are independent. Note that if the print option is active, while the click operation write on disc the random color, the unclick operation write on disc also the main color.
Click/unclick = random color/main color.
For distant planets and their moons always check the physical ephemeris against the LT, light travel, delay ("_" underscore tap).
CREDITS:
To Marco Klunder, who have shared with me the knowledge of its ObjectsRiseSet plugin, and for having solved an "interpolation issue" for fast Sun-orbiting planets (mainly Mercury and comets). The visual ephemerides in the part of the rise/set times is basically due to him. My credits with Marco are shown like comments also in the code for the Moon rise/set, being its work with the fundamental arguments (Van Flandern & Pulkkinen, 1979) and their LUA port from SKY AND TELESCOPE BASIC Sun/Moon code, originally extended thereafter to all planets including Pluto, and in which the trigonometric series were compiled until the last(!) argument prior to be bypassed under the suggestion of using the Celestia's CELX/LUA scripting for get RA, Dec. I've left its work for the Moon like a legacy of its rigorous and time-consuming task.
To Joël (Jogad) for finding a manageable solution for the ephemerides' bar behaviour in windowed mode;
its code has been seamlessly nested within the "ephemerisBox.lua", bringing the plugin to a next step in enhancement.
Ephemerides 2.5Note: this version is the latest version of this plugin and it is intended to be the start version for CM. Respect to the 2.4 version now removed from Shatters.net it add:
- Constellations for Sol; constellations are now set up upon the true path of the Sun and no longer zodiacal based. Added "pede serpentarii" to the constellations and thereafter your sign no longer will be what you think;
- Length of the day;
- seconds to the equinoxes/solstices times;
- Updated EN, FR, NL, IT languages for new features;
- minor display fixes.