Revision D of predicted GDC Ephemerides -- official ephemerides and prototype ephemerides used in Shim et al (2025) paper

"RevDEphemsOfficial.zip": a ZIP archive containing eighteen ASCII / CSV data files containing full predicted ephemerides for the prime GDC mission, Reivision D (latest as of September 15, 2025). The file timestamps are in UTC, and each of the six spacecraft (G1 through G6) ephemerides are in a separate file, with further separation by mission phase (Phase1, Phase2, Phase3). The header contains the column data identifiers and units: Time (UTCG) (time in coordinated universal time, in DD Mon YYY HH:MM:SS.MMM format X-J2K(km), Y-J2K (km), Z-J2K (km): J2000 (earth-centered inertial) cartesian coordinates with the satellite position from Earth center, in km Vx-J2K (km/sec), Vy-J2K (km/sec), Vz-J2K (km/sec): J2000 (earth-centered inertial) cartesian velocity components in km/sec LAT (deg), LON (deg): geodetic latitude and longitude of the subsatellite footpoint in degrees ALT (km): altitude above the WGS84 geoid -- note, in these simulations, orbital drag is not accounted for, so othe altitude varies only with latitude, and not with time (at a given latitude)Xsun-J2K, Ysun-J2K, Zsun-J2K: x,y,z components of cartesian unit vector from earth center to Sun, in J2000 coordinates Xpm-J2K, Ypm-J2K, Zpm-J2k: x,y,z components of cartesian unit vector from earth center to the point on the earth's surface where the equator and prime meridian intersect ------- "GDC_RevD_primemission_orbit_visualization.mov.zip": ZIP archive containing a QuickTime movie showing the evolution of the constellation ephemerides for an arbitrary launch day and launch local time. ------ "Shim_et_al_2025_magnetic_cd_ephems.zip" prototype (non-official) ephemeris files for GDC, in centered-dipole magnetic coordinates, courtesy of Dr. Denny Oliveira (UMBC). These are based on a prototype earlier version of the Rev D ephemeris (superseded by the "official" files listed above. The file format has column headers year, month, day, hours, minute, second, geographic latitude, geographic longitude, satellite altitude, solar local time, magnetic latitude, magnetic longitude, magnetic local time. These are the magnetic coordinates used in the OSSE studies of Shim et al (2025)