KPL/PCK
The mkspk application needs the data in this kernel to produce
type 10 SPK segments based upon the two-line element sets available
from NORAD/SPACETRACK. The data applies ONLY to the Two Line Element
sets and only to the Spacetrack 3 SGP/SDP implementations included
in the SPICE library [1]. Mkspk copies this data to the constants
partition of the type 10 segment, so the user has no need for the kernel
after creation of the corresponding SPK.
Bill Taber (JPL)
Ed Wright (JPL)
All values take from the Spacetrack #3 report.
The first 3 numbers are the gravitational harmonics for
the earth. These numbers are dimensionless.
\begindata
BODY399_J2 = 1.082616D-3
BODY399_J3 = -2.53881D-6
BODY399_J4 = -1.65597D-6
\begintext
The next item is the square root of GM for the earth given
in units of earth-radii**1.5/Minute
\begindata
BODY399_KE = 7.43669161D-2
\begintext
The next two items give the top and bottom of the atmospheric
drag model used by the type 10 ephemeris type.
\begindata
BODY399_QO = 120.0D0
BODY399_SO = 78.0D0
\begintext
Tthe equatorial radius of the earth in kilometers as used by NORAD.
\begindata
BODY399_ER = 6378.135D0
\begintext
The value of AE is the number of distance units per earth
radii used by the NORAD state propagation software. Don't
change this value.
\begindata
BODY399_AE = 1.0D0
\begintext
References:
[1] Hoots, F. R., and Roehrich, R., l. 1980. "Spacetrack Report #3, Models
for Propagation of the NORAD Element Sets." U.S. Air Force, CO.