DESCRIPTION OF IDE ARCHIVAL PRINTOUT-

original authored by Bill Cooke

DESCRIPTION OF IDE ARCHIVAL DATA FILE

The archival file consists of 16 columns of information. A description of each column, along with a suggested variable name and the format of the column (in FORTRAN notation) is given below:

Column 1, Variable: DAD, Format: F9.4
This is the time of the event, in days from LDEF deploy (1984 April 7 14:15:25 0.35, or, in terms of days from the beginning of 1984, 98.594034 0.000004).
Column 2, Variable: DOY, Format: F9.4
This is the UT time of the event in days from the beginning of 1984.
Column 3, Variable: IDE, Format: I8
This column gives the IDE clock time of the event, in IDE ticks (13.10164 seconds per tick).
Column 4, Variable: TRAY, Format: A1 This column identifies the IDE tray struck. There are six possible single-letter identifiers (N, S, E, W, U,and D):
- E - East tray, or leading edge, which faced approximately in the direction of LDEF ram.
- W - West tray, or trailing edge, which faced roughly in the direction of LDEF wake (anti-parallel to the velocity).
- N - North tray, which faced approximately in the direction of the LDEF orbit's north pole.
- S - South tray, which faced approximately in the direction of the south pole of the LDEF orbit.
- U - Space tray (Up), which faced radially outward along the LDEF distance vector, towards space.
- D - Earth tray (Down), which faced radially inward along the LDEF distance vector, towards the center of the Earth.
Column 5, Variable: N4, Format: I3
This column gives the number of impacts recorded on the 0.4 micron (high sensitivity) detectors mounted on the tray indicated by column 3 during this IDE clock tick.
Column 6, Variable: N10, Format: I3
This column gives the number of impacts recorded on the 1.0 micron (low sensitivity) detectors mounted on the tray indicated by column 3 during this IDE clock tick. Column 7, Variable: RAL, Format: F6.1
This column gives the geocentric right ascension, in degrees, of LDEF at the time of the event. The coordinates are referred to the 1950.0 equatorial system.
Column 8, Variable: DCL, Format: F6.1
This column gives the geocentric declination, in degrees, of LDEF at the time of the event. The coordinates are referred to the 1950.0 equatorial system.
Column 9, Variable: ELNG, Format: F7.1
This column indicates the sub-LDEF longitude at the time of the event, i.e., the longitude of the point on the Earth directly below LDEF when it was struck. Measured in degrees, the longitude is positive east of the Greenwich meridian and negative west of Greenwich.
Column 10, Variable: ECL, Format: F6.1
This column gives the difference between the ecliptic longitude of LDEF and that of the sun, in degrees, at the time of the event.
Column 11, Variable: BETA, Format: F6.1
This column gives the ecliptic latitude of LDEF, in degrees, at the time of the event.
Column 12, Variable: SEL, Format: F6.1
This column indicates the geocentric angle (in degrees) between the directions to the sun and LDEF at the time of the event.
Column 13, Variable: RAN, Format: F6.1
This column gives the geocentric right ascension, in degrees, of the direction of normal vector to the impacted tray. The coordinate system is once again the 1950 equatorial system.
Column 14, Variable: DCN, Format: F6.1
This column gives the geocentric declination, in degrees, of the direction of normal vector to the impacted tray. The coordinate system is once again the 1950 equatorial system.
Column 15, Variable: SN, Format: F6.1
This column gives the angle (in degrees) between the solar direction and the impacted tray normal at the time of the event.
Column 16, Variable: THETA, Format: F6.1
This column indicates the true ecliptic longitude of the Sun, in degrees, at the time of the event.

FORTRAN READ STATEMENT:

The following FORTRAN statement will read each line of the data file, storing the appropriate values into the variables defined above:

       READ (3, 300) DAD,DOY,IDE,TRAY,N4,N10,RAL,DCL,ELNG,
     &                         ECL,BETA,SEL,RAN,DCN,SN,THETA
300  FORMAT (2F9.4,I8,1X,A1,2I3,2F6.1,F7.1,7F6.1)

IDE database home page

Klaus G. Paul, 6-24-1994