This file contains the history of the aperture pointing.
The APPH file contains a primary header with the fields described in Table D.6. In this example non-mandatory fields are filled with example values.
| Keyword | Value | Description |
| SIMPLE = | T | / |
| BITPIX = | 8 | / |
| NAXIS = | 0 | / |
| EXTEND = | T | / |
| ORIGIN = | 'ESA ' | / European Space Agency |
| TELESCOP = | 'ISO ' | / Infrared Space Observatory |
| COMMENT | Attributes of instantiated Observations | |
| FILENAME = | 'APPH ' | / File name in ISO archive |
| DATE = | '09/07/95' | / Creation date |
| FILEVERS = | '0298 ' | / Version ID in ISO archive |
| OLPVERS = | 'OLP_21 ' | / SOC OLP system version |
| CALGVERS = | 'CALG_31 ' | / SOC OLP CAL-G files version |
| USERNAME = | 'PIPELINE' | / |
| TSTART = | '96117194942' | / Start time of interval covered (YYDDDHHMMSS) |
| TSTOP = | '96118194608' | / End time of interval covered (YYDDDHHMMSS) |
| GENTIM = | '96118164552' | / Time of generation of this file (YYDDDHHMMSS) |
| REVNUM = | 162 | / Revolution number |
| APHVERS = | 1 | / APH version number |
The APPH file contains records described in Table D.7.
| Keyword | Number | Format | Description |
| SLEWSTA | 2 | I4 | Start time of slew to target as seconds since |
| 1989.0 (UTC) followed by remaining fraction of second | |||
| SLEWEND | 2 | I4 | End time of slew to target, as above |
| RA | 1 | R8 | RA of intended view direction in degrees |
| DEC | 1 | R8 | DEC of intended view direction in degrees |
| OTFTHRES | 1 | R4 | On-target flag threshold in arcsec |
| INSTID | 1 | A1 | Instrument ID (C,L,P,S or Z for QSS) |
| REQTYPE | 1 | A1 | Type of request: 'P'ointing, 'R'aster or 'T'racking |
| APERTID | 1 | I2 | Aperture identification: from 0 to 4 |
| NGRID | 1 | I2 | Number of grid points on a
scan, from 1 to 32 |
| NRASTER | 1 | I2 | Number of lines in the raster,
from 1 to 32 |
| TSLEW1 | 1 | I2 | Time to slew and dwell on 1st
point |
| TSLEW2 | 1 | I2 | Ditto for a point on the current
line |
| TSLEW3 | 1 | I2 | Ditto for 1st point on next
line |
| SCANDIST | 1 | I2 | Distance between points on a scanline. Units are usually |
| arcseconds but if REQTYPE=`T' then SCANDIST is | |||
| defined in units of 0.01
arcseconds |
|||
| LINEDIST | 1 | I2 | Distance between scan lines in
arcsec |
| ORIENT | 1 | I1 | Orientation raster flag |
| 0=Raster at an angle ROTATE to North | |||
| 1=Raster starts parallel to the S/C y-axis | |||
| SPARE | 5 | I1 | Spare |
| ROTATE | 1 | R4 | Rotation of raster pattern,
in degrees. 0  ROTATE 360 |
| QSSQUAT | 4 | R8 | QSS quaternion for the intended viewing direction. |
| Refers to raster centre if REQTYPE is R or T | |||
| MISQUAT | 4 | R8 | QSS/Star-Tracker misalignment quaternion |
| STARVEC | 3 | R8 | Guide star unit vector |
| REFSTAR | 1 | R4 | Guide star reference number in catalogue |
| SOLASPCT | 1 | R4 | Solar aspect angle, in degrees |
| RPEAMP | 1 | R4 | RPE amplitude, in arcsecs |
| ATTCONT | 1 | I1 | Attitude continuation flag |
| 1=different aperture but same instrument and target | |||
| as previous record | |||
| 0=otherwise | |||
| CONTINGE | 1 | I1 | Contingency flag |
| 0=no contingency | |||
| 1=target attitude not acquired | |||
| 2=no QSS/STR misalignment available | |||
| SPARE2 | 2 | I1 | Spare |