This session will include solicited, contributed and poster papers with the focus on observations from the earth and spacecraft, together with papers on theoretical interpretations, results of modelling and pertinent laboratory measurements. Neutral atmospheres and their relationship to surface, interior and magnetospheres of the outer planetary systems will be emphasized. Presentations on new results from the Cassini-Huygens and Galileo missions and from the New Horizon's Jupiter flyby, as well as from earth-based observations will receive special consideration.

Objects discussed in the session are the giant planets, Titan, Triton, Enceladus, Galilean satellites with atmospheres and Pluto. Comparative planetology approach is encouraged, where applicable.

Abstracts on rings and icy satellites without atmosphere should be sent to Session PS3.2.