Program Mercury.java does the following:
1) The simulation shows only the sun and Mercury. A pole points
out from
Mercury's equator pointing at the sun at start time time. The pole
shows
that Mercury's day is twice as long as its year.
2) The Sun is yellow. Mercury has an orange daylight portion and
a grey
dark portion. A white pole protrudes from Mercury's equator
so that
the rotation of Mercury can be followed.
3) The orbital distances and sizes of Mercury and the Sun are not
to scale.
4) The program's "Earth Days " shows elapsed time on the earth.
The
program displays the number of years and solar days on Mercury.
5) The program updates the positions once per simulated day.
The once per
day integration uses mean values. The actual orbit of Mercury
speeds up
and slows down due to the eliptical nature of Mercury's orbit.
6) Values used in this simulation:
Sidereal year for Mercury - 87.969
earth days or 4.0923 deg.
heliocentric longitude / day.
Sidereal axial rotation for Mercury
- 58.65 earth days or 6.1381 deg.
rotation / earth day.
Version: May 2, 2000 by Victor McAllister