SOLAR SYSTEM 3D plotting script for GNUPLOT 4.4 or higher N-Body data are from DE405 ephemerides 
documentation

http://iau-comm4.jpl.nasa.gov/de405iom/

and locally integrated with a high-precision Bulirsh-Stoer integration scheme. The x-y-z and 
vx-vy-vz data are stored in si_xyz.out and si_xyz.out, respectively. Currently, the velocities 
are not used. However, both data sets may be used as initial conditions set for own N-body 
calculations.

List of files:

README.txt              This file

---- Sourcecodes ----
Makefile                Makefile for sidate and cleaning
sidate.f                Picks data from si_xyz, times.out and sie.aux for given time
date_routines.f         Calendar calculation (e.g. Julian day to calendar date conversion)
polint.f                Polynomial interpolation routine
n2char.f                Conversion of integer to string (10-character)
sol3d.gp                Gnuplot main script
skyglobe4sol3d.gp       Sky globe plot
3dcharts4sol3d.gp       3D space plot
2dplots4sol3d.gp        Additional 2-D plots (loaded from sol3d)
styles.gp               Linestyles and colors (loaded from sol3d)
nightstyles.gp          Same, but for black background option
anglefuncs_deg.gp       Some auxiliary scripts...
anglefuncs_rad.gp
rotfuncs.gp
columns.gp
psizes.gp
globegrid.gp
window4sol3d.gp
divfuncs.gp
rgbstring4sol3d.gp

---- Pre-calculated data ----
su_date.out             Timetable
si_xyz.out              Center-of-mass coordinates of the 11 bodies from 1900-2200.
solxyz2000-2600d100.asc 100-day resolution, 600 years coordinates for orbit plotting
solxyz2000-2060d010.asc 10 day resolution, 60 years (best for planets up to Uranus)
solxyz1000day.asc       1 day resolution, 1000 days (best for inner planets)
solxyz100.0day.asc      0.1 day resolution, 100 days (best for inner planets and moon)
sid.par                 Auxiliary data (axis unit verctors etc.)

---- Data from the web ----
near50sol3d.asc         Nearby stars within 15 parsecs (http://www.atlasoftheuniverse.com/)

---- Input files ----
sidate.inp              Date and time selection

Other files are created by sidate (sidate.xyz, .uvw, .tab, .aux) and sol3d (npole.dat).

**** GETTING STARTED ****

First, make sure that gnuplot 4.4 or higher, and gfortran is installed. Furthermore, X11 must be 
available for full usage. On systems without X11, no mouse scrolling may be available.

Then, to create the date picker program SIDATE (Solar System Integrator Datepicker), type

make sidate

Enter the target date as year month day in sidate.inp and the local time as hour minute second, 
as well as the difference to UTC (i.e. timezone plus optional DST). Additionaly, you may choose 
whether interpolation of the tabulated motion data is desired. If between 2 and 10 the number is 
equivalent to the degree of the interpolation polynomial (4 is recommended). If switched off, the 
time can be adjusted in sol3d ad well.

In sol3d, you may enter the latitude, the local time of the day and offset indepentendly; this 
will overrun the time settings in sidate.inp (and should therefore not be the regular method). 
All times appear as decimal numbers (except for some label output), i.e. 22:45 appears as 22.75. 
You may also adjust the zoom scale and the central body (Earth is 3, Sun is 11), and the window 
size (in the set term command line, in pixels), and the actual plotting command (at the lower 
end).

Now, start gnuplot and type

load 'sol3d.gp'

The 3D window gives an external view of the selected solar system volume for the given date. The 
radial grid plane is the tangential plane of Earth's surface at your location. The rectangular 
grid plane indicates the Ecliptic. Both can be enabled and disabled by the flgsurf and flggrid 
params (1 for coarse, 2 for fine grid). The rotation flag enables the aligment of the rect. grid 
to the Ecpliptic (or any other manually specifief plane); if <=0 then it is in the x-y-plane.

Instead of the full 3D view sometimes a "globe" view is preferred. The last splot command 
collapses al radii to the same unit. Now, all bodies appear on the "sky" (which is still observed 
from outside). In addition, also a rectangular and polar azimuth-altitude plot is available 
(uncomment the according plot commands). This is loaded from an external file named '2dplots.gp'.

Two other external files define the plotting styles. 'styles.gp' is for the standard white 
background. If you prefer a black background, then choose 'nightstyles.gp' and start gnuplot with 
a background color option:

gnuplot -background black -xrm 'gnuplot*borderColor:#00aaff'

The other colors are defined in the  styles files (there is a bug in the released version 4.42
that prevents the key text color in splot from being set. It is fixed in the development
version.) For details on gnuplot see the gnuplot documentations.

As a first example, set the system time flag (the fourth number in the first line) in sidate.inp
to zero, then run sidate.x and then sol3d.gp on gnuplot. Make sure that the longitude and
latitude in sol3d.gp are set to Marxzell-Burbach (one of the pre-defined lines, toggled via a
leading comment character, '#'). Now you'll see the Sun and the Moon at the same position on
the sky globe. That's because the default date is near the maximum of the 1999 solar ecplise!
Now set the date line to any date between 1900 and 2200, or set the system time flag to 3 again
(i.e. automatic date, time and timezone), and set your preferred location in sol3d.gp (close
to the other location lines, after deactivating them by commenting them out with the '#').

Enjoy!
