Eisinga's Digital Planetarium

Date: Speed: Positions according to: Color scheme: Special days:

Day count since 1781-02-21:0 ... of which are leap days:0

Explanatory notes

This planetarium is a simple simulation of the planetarium in Franeker. The celestial bodies are from center to outer ring: the Sun, Mercury, Venus, Earth, Mars, Jupiter and Saturn.

The rotational speeds are as Eisinga approximates them, calibrated at the planet's positions in 1781. As those are not sufficiently precise to appromiximate nowaday's planet positions, it is possible to choose De Lalande's rotational speeds, that remain to be sufficiently accurate.

Sources

Rotational speeds

Planetarium-boek Eise Eisinga, 1928-08-27
- E. Havinga
- W. E. van Wijk
- J. F. M. G. d'Aumerie

Calibrated planet positions

NASA Horizon

Credits

Source code and editing: René van den Berg
Graphic design source material: Rijksmuseum