USER MANUAL
- Sizes are proportional to each other and the distances are proportional to each other. But It is not possible to display with both minor planet sizes and distances in scale.
- 3D rotations : click on the scene + drag and drop
- click on a minor planet to select it and see his orbit
- Zoom / unzoom : with the mouse wheel.
- Run the animation : Green Button "PLAY / PAUSE" on the top left.
- Step of the animation : list box "STEP" : Select the unit of time (hours, days, weeks,...)
- For the current position of celestial objects : Button "NOW"
- To select a target : on the top right choose the celestial object type that you want : planets, minor planets, ...
NB: If target is not checked, no object will be selected
- "Visibility" : choose wich type of celestial objects must appear on the screen, with his label or not, with his orbit or not
- in "Visibility" you can also activate filters :
... for example, show only minor planets with estimated diameter > 400 km and major axis < 4 UA (= absmag max < 5, major axis max < 4)
- Dans "Others++", you can change the focal of the 3D scene, the objects or labels sizes, etc
- Printscreeen : Button with the camera (format between A4 until A2)
REFERENCES
- spacecraft trajectory : http://ssd.jpl.nasa.gov/horizons.cgi#top
- the minor planets data come from http://www.minorplanetcenter.net/iau/MPCORB
- Celestial objects positions (minor planets, asteroids, comets) are computed with Keplers law (two-body problem). Kepler's equation M = E - e * sin E
- Algorithms are described on http://www.stjarnhimlen.se/ - See also the book ASTRONOMICAL ALGORITHMS, J. MEEUS.
- Algorithm to compute approximate planetary positions (valid for the time-interval 3000 BC - 3000 AD): see on http://ssd.jpl.nasa.gov/?planet_pos
- The accuracy requirements for a visualisation at the scale of the solar system are modest (approximation of about one million kilometers)