APPENDIX F

THE IRIS DATA

This appendix presents the IRIS data set itself. All on-planet spectra with a range of less than 400,000 km are listed, with 5 tables covering each spacecraft encounter with each icy satellite.
First I give the FDS count, then the spacecraft range, in kilometers, from the planet center, and the subspacecraft latitude and longitude. Longitudes are given using the pre-Voyager system, with zero at the sub-Jupiter point. Then follows postitional information for the center of the IRIS field of view (corrected values in the case of Voyager 2 Ganymede (see Chapter 3)). I give, in order, the latitude and longitude, local time in degrees (`LTim'), solar incidence angle (i), emission angle (e), minimum separation of the field of view from the limb, in degrees (`LSp': negative values indicate dark-sky contamination, see Chapter 4), and solar phase angle (`Phs'). Then, for most Ganymede spectra, `f_Dk' and `f<sub>Ct</sub>' give the percentage of the field of view occupied by dark cratered terrain and bright crater materials respectively (Chapter 3).
Finally I list the spectrum shape and temperature information. T<sub>1</sub>, T<sub>E</sub>, \dt, and \ep\ are the fitted warm-component temperature, effective temperature, temperature contrast, and emissivity, as defined in Chapter 4. T<sub>1</sub> is redundant but it, and thus T<sub>2</sub>, cannot be derived analytically from T<sub>E</sub>, \dt, and \ep, so it is given for convenience. `Slp' is the standardized slope of the fitted spectrum: the difference in brightness temperature between 500 and 250 cm^-1. A few spectra (usually those with dark-sky contamination) could not be fitted: for these only the `raw' 22 microns brightness temperature is listed, in the T_E column.