1 Table of Contents: “...Planet Earth -- Oman during Precambrian -- Oman during Palaeozoic -- Oman during Mesozoic -- Oman...”

2 Table of Contents: “... into the Atmosphere of Terrestrial Planets -- Interaction of Comets With the Interplanetary Medium -- Chemical...”

3 Table of Contents: “... -- Nature and Origin of Organic Molecules in Comets -- Liquid Water on a Planet over Cosmic Periods...”

4 “.... Previous colloquia had emphasized the Giant Planets (1974) 1, Early Life during the Precambrian (1975)2...”