----+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
POLDYN 880901 0. 0. 3. 3.
----+----0----+----0----+----0----+----0----+----0----+----0----+----0----+----0
COLUMNS FORMAT DESCRIPTION DEFAULT VALUE & UNITS
1-6 A6 POLDYN - Requests application of
dynamic polar motion.
15-20 I6 Start time for application of drift Epoch time on
rates in YYMMDD format. EPOCH card
25-44 D20.8 X pole value corresponding to the 0. MAS
six year average true of date axis
at the epoch specified in columns
15-20
45-59 D15.3 Y pole value corresponding to the 0. MAS
six year average true of date axis
at the epoch specified in columns
15-20
60-72 D12.8 X drift rate for the six year average 0. MAS/Yr.
axis specified in columns 25-44.
73-80 D8.3 Y drift rate for the six year average 0. MAS/Yr.
axis specified in columns 45-59.
NOTES:
See POLKF option for setting the figure axis scale factor that
is used with the dynamic polar motion model.
See the following page for the dynamic polar motion formulation.
UNITS: KM =Kilometers; M =Meters ; S =Seconds ; M/S=Meters per second
MAS=Milliarc seconds
IF CARD OMITTED: Dynamic polar motion will not be applied.
MAR 1989
8901.0
GLOBAL SET
POLDYN (cont)
The Dynamic Polar Motion formulation is given below:
_ _ _
C(2,1) = C(2,1) + Kf * (Xp(t) - (Xp(t0)+Xpdot*(t-t0)))*C(2,0)*SQRT(3)
_ _ _
S(2,1) = S(2,1) - Kf * (Yp(t) - (Yp(t0)+Ypdot*(t-t0)))*C(2,0)*SQRT(3)
t0 - Date for the six year average polar motion axis. Start
time for application of polar motion drift rates.
Xp(t0),Yp(t0) - Pole values corresponding to the six year average
true of date axis at the epoch t0.
Xp(t) ,Yp(t) - Pole values at time t.
Xpdot,Ypdot - Drift rates for the six year average pole values.
_ _
C(2,0),C(2,1) - Normalized geopotential C coefficients
_
S(2,1) - Normalized geopotential S coefficient.
Kf - Figure axis scale factor. To change the Figure Axis
scale factor Kf see the POLKF option.
SQRT(3) - Required because the geopotential coefficients are
normalized.
JUNE 1991
9106.0
GLOBAL SET