Card 6t - ORBDEF6 Full or Partial Orbit Parameters
This optional card defines the full or partial orbit parameters.
| Parameter | Value | Description |
|---|---|---|
ORBDEF6 |
ORBDEF6 or 46 | mnemonic |
ID |
Integer | ID number |
SEGTYPE |
FULL | Full orbit |
| PARTIAL | Partial orbit | |
STARTPOS |
AN | S/C starting position is defined w/rt ascending node |
| DN | S/C starting position is defined w/rt descending node | |
| LN | S/C starting position is defined w/rt local noon | |
| LM | S/C starting position is defined w/rt local midnight | |
| PE | S/C starting position is defined w/rt perigee | |
| AP | S/C starting position is defined w/rt apogee | |
STARTANGLE |
Real | S/C starting angle w/rt the starting position |
TIMEI |
Real | Initial computational time |
ENDANGLE |
Real | S/C end angle w/rt starting position |
NINT |
Integer | Number of orbital position or negative of table number value |
SEGTYPE
SEGTYPE is the flag specifying whether the orbit is full or partial.
STARTPOS
STARTPOS is the flag specifying the position from which the start angle (and end angle for a partial orbit) is referenced.
Refer to the diagram in Card 6l – Additional Orbital Parameters ORBADD Card – Optional for the illustration of the PE option.
For ORBDEF4 Card GEO option, only the LN and LM options are valid.
STARTANGLE
STARTANGLE is the angle in degrees of the start position from the reference point defined in STARTPOS. The angle is measured in the orbit plane and is positive in the direction of motion of the spacecraft.
TIMEI
TIMEI is the analysis time associated with the start angle of partial orbits. For full orbits it should be 0.
ENDANGLE
ENDANGLE is the angle in degrees of the end position from the reference point defined in STARTPOS for partial orbits. The angle is measured in the orbit plane and is positive in the direction of motion of the spacecraft. For full orbits it should be 0.
NINT
NINT is the number of equal angular intervals at which the orbital fluxes will be calculated.
If the angle positions are specified in a table, then:
- NINT must be < 0, and then the abs(NINT) is a table number defined in Card 9 TABTYPE and TABDATA Cards containing the angular positions.
- On the TABTYPE Card, the dependent variable must be ROTAT, and the independent variable must be TIME. On the TABDATA Cards the dependent variable must be an angle in degrees, while the value of the independent variable is ignored (it does not have to be time).