Computes the geomagnetic field and
various parameters associated with the geomagnetic field. Valid for
vehicles whose central body is earth.
| Name |
Dimension |
Type |
Description |
| Time |
DateFormat |
Real Number |
Time. |
| Total intensity
F |
MagneticFieldUnit |
Real Number |
The magnitude of the magnetic field at the
vehicle's location. |
| North intensity
X |
MagneticFieldUnit |
Real Number |
The North component of the magnetic field vector,
at the vehicle's location. |
| East intensity Y |
MagneticFieldUnit |
Real Number |
The East component of the magnetic field vector, at
the vehicle's location. |
| Vertical
intensity Z |
MagneticFieldUnit |
Real Number |
The vertical component of the magnetic field
vector, at the vehicle's location. Vertical is measured positive
toward the earth along the detic nadir direction. |
| Horizontal
intensity H |
MagneticFieldUnit |
Real Number |
The horizontal component of the magnetic field
vector, at the vehicle's location. This is the square root of X^2 +
Y^2. |
| Magnetic
declination D |
AngleUnit |
Real Number |
The angle between the horizontal projection of the
magnetic field vector and the direction to north, at the vehicle's
location. The value is the arctan(Y/X). Also called magnetic
variation. |
| Magnetic
inclination I |
AngleUnit |
Real Number |
The angle between vertical projection of the
magnetic field vector and the north-east plane, at the vehicle's
location. The value is the arcsin(Z/F). |
| Dipole
L-shell parameter |
Unitless |
Real Number |
The L value for the field line passing through the
vehicle's location computed using the dipole approximation to the
magnetic field. For a dipole field line, the L value corresponds to
the distance, measured in earth mean radii, at the point on the
field line at the magnetic equator. (For a dipole field, this point
is also the furthest extent of the field line from the earth.) |
| McIlwain L-shell parameter |
Unitless |
Real Number or Text |
A measure that indicates a particle's drift shell
in the magnetic field at the vehicle's location, as defined by Carl
McIlwain (J. Geophys. Res. 1961). The value is computed as a
function of several magnetic invariants along a field line and thus
its computation requires field line tracing. It is not strictly a
constant over the entire field line. In cases where the field line
is close to the dipole field line (i.e., the field line traced
using only the dipole component of the magnetic field model), the
value will be close to the dipole L-shell parameter. |
| McIlwain Abs(L-shell)
parameter |
Unitless |
Real Number or Text |
The absolute value of the McIlwain L-shell
parameter |
| B/Beq |
Unitless |
Real Number or Text |
The ratio of the magnetic intensity at the
vehicle's location to the minimum magnetic intensity along the
field line through the vehicle's location. |
| Beq |
MagneticFieldUnit |
Real Number or Text |
The minimum magnetic intensity along the field line
through the vehicle's location. The minimum value occurs at the
magnetic equator, at the furthest extent of the field line from the
earth. |
| B Field - ECF x |
MagneticFieldUnit |
Real Number |
The x-component of the magnetic field vector at the
vehicle's location, expressed in Earth Fixed axes. |
| B Field - ECF y |
MagneticFieldUnit |
Real Number |
The y-component of the magnetic field vector at the
vehicle's location, expressed in Earth Fixed axes. |
| B Field - ECF z |
MagneticFieldUnit |
Real Number |
The z-component of the magnetic field vector at the
vehicle's location, expressed in Earth Fixed axes. |
| B Field - ECI x |
MagneticFieldUnit |
Real Number |
The x-component of the magnetic field vector at the
vehicle's location, expressed in Earth ICRF axes. |
| B Field - ECI y |
MagneticFieldUnit |
Real Number |
The y-component of the magnetic field vector at the
vehicle's location, expressed in Earth ICRF axes. |
| B Field - ECI z |
MagneticFieldUnit |
Real Number |
The z-component of the magnetic field vector at the
vehicle's location, expressed in Earth ICRF axes. |
| B Field - Body x |
MagneticFieldUnit |
Real Number |
The x-component of the magnetic field vector at the
vehicle's location, expressed in the vehicle's body axes. |
| B Field - Body y |
MagneticFieldUnit |
Real Number |
The y-component of the magnetic field vector at the
vehicle's location, expressed in the vehicle's body axes. |
| B Field - Body z |
MagneticFieldUnit |
Real Number |
The z-component of the magnetic field vector at the
vehicle's location, expressed in the vehicle's body axes. |