Orbit Retrieval Subroutines

Description

This data set, provided by the principal investigator, consists of Magsat user subroutines on EBCDIC magnetic tape created on an IBM 360 computer. These subroutines were prepared to permit retrieval of orbit data from orbit records on Magsat chronicle tapes. The spacecraft position in Cartesian (X, Y, and Z in km), geographic (latitude and longitude), and geomagnetic coordinates can be obtained by calling subroutine FLDORB, specifying time as modified Julian day (MJD) and milliseconds of day. Subroutine FLDORB also provides magnetic local time, dip latitude, and a magnetic field value from a field model. An additional subroutine converts from MJD to calendar date and vice versa. Additional information can be obtained from the prologues in the source code listing.