A number of very bright astronomical targets that are observable with ISO cannot be observed with the P1 detector because of the risk of possible damage to the cold read-out electronics. The flux of these sources is far above the saturation limits given in Table 6. To guard the instrument safety, all P1 observations will be rejected by the ISO scheduling system in case they point too close to the sources listed in Table 7. For Jupiter, observations with PHT-S are prohibited, too.
Observations are rejected in case the distance to the targets presented in Table 7 is less than 6 arcmin in fine pointing mode and less than 7.5 arcmin in chopped mode. For PHT03 observations using the raster option the distance of the map center to the sources of Table 7 has to fulfill the following requirement:
where m is the number of raster legs, n is the number of raster points and
m and n are the raster step sizes in m and n directions.
The raster option is not available for PHT04, PHT05, PHT17, PHT18, and PHT19.
