Viewing angles. Three angles are defined to specify
the viewpoint. The first two angles determine the position of the Earth's
rotation axis with respect to the screen, whilst the third produces motion
about the Earth's rotation axis, as illustrated in the figure below.
Viewing angles for 3D-visualisation
The different rotations are executed in the same order as described here.
The starting position puts the Earth's rotation axis vertical and the
Greenwich meridian pointing towards the viewer (top left figure).
First, the 3D-image is rotated about a horizontal axis in the
plane defined by the screen. A positive angle tilts the north pole towards
the viewer and the south pole away from the viewer (top right figure,
Then, the 3D-image is rotated about an axis perpendicular to the
screen. A positive angle tilts the Earth's rotation axis to the left (i.e.
counterclockwise, bottom left figure, 10°).
Finally, a rotation about the Earth rotation axis is
executed. A positive angle rotates the Earth in a clockwise direction, such
that, if the north pole is positioned in the upper part of the drawing, the
meridian with the specified longitude will be pointing towards the viewer
(bottom right figure, -60°).
A plot showing the orbit in three dimensions with respect to the
GEO coordinate system.
This representation requires a VRML plug-in for the browser that is used.