Most celestial objects fall into the category of normal targets. For ISO every object with fixed celestial coordinates is a normal target. The coordinate information has to be given with an accuracy of 1 arcsec in Declination and 0.1s in Right Ascension. This is also the required accuracy at least for the smaller entrance apertures of ISO. IRAS positions are thus generally not precise enough for ISO.
In order to avoid incorrect pointing, proper motion has to be given for objects such as nearby stars. The proper motion has to be given in arcsecyr . Note that the given coordinates should correspond to an epoch which is the same as the epoch used for the coordinate system.