Kidney shaped orbit of 3753 Cruithne
In the previous integration we observed
Cruithne in an elliptical 1:1 resonant
orbit with Earth. Here we see it again but rotating coordinates are
being used so that Earth is constantly in the same direction relative
to the Sun.
Observe the pattern of movement to see how Cruithne travels round
its orbit. Now switch off the orbit lines using the
orbit control and see the asteroid's
'kidney' shaped path relative to Earth. Each year the 'kidney' is
drawn a little further away from Earth until it approaches from the
other side after about 290 years. At this point it reverses direction
and the 'kidney' starts moving back in the opposite direction. This is
in effect another form of Horseshoe orbit.
This integration includes Asteroid 3753 Cruithne and all the main
bodies of the Solar System. Earth and 2002 AA29 are shown in their
normal colours while the others are shown faintly. Rotating
coordinates are used to keep the Earth approximately static although
it does wiggle a bit due to its slightly elliptical orbit.
Note: Longer term integrations have shown that Cruithne is
inconsistent as to when it reverses direction in Horseshoe mode.
Sometimes the reversal happens when the close approach is near
Cruithne's ascending node and sometimes when the approach is near its
descending node. |
