The Space Oblique Mercator (SOM) projection is a modified cylindrical projection with the map surface defined by a satellite orbit. The SOM is an extremely complicated projection. We urge you to refer to "Map Projections a Working Manual" by Snyder for a detailed explanation.
The SOM projection was designed especially for continuous mapping of satellite imagery.
The "SpaceObliqueMercator" Projection has the following Parameters:
|
Parameter Name |
Parameter String |
Units |
|
Longitude of the Center of the Projection |
central_meridian |
|
|
Geodetic longitude of the ascending node at time t=0 |
satellite_lon0 |
|
|
Length of Earth's rotation with respect to the precessed ascending node |
satellite_p1 |
Double |
|
Time required for revolution of the satellite |
satellite_p2 |
Double |
|
Semi-major Axis of the Satellite Orbit |
satellite_a |
|
|
Eccentricity of the Satellite Orbit |
satellite_e |
Double |
|
Inclination of the Satellite Orbit |
satellite_incl |
|
|
Longitude of the perigee relative to the ascending node |
satellite_gamma |
Double |
NOTE: The ellipsoidal form with a non-circular satellite orbit is the current implementation.