In memoriam:  James B. Pollack (1938-1994).
Toon
B
B
NASA/Ames Research Center, USA.
Cuzzi
J
J
Sagan
C
C
D001256:Astronomy / Q000266:history*; D018559:Exobiology / Q000266:history; D005118:Extraterrestrial Environment; D049673:History, 20th Century; D016083:Planets; D014481:United States; D018557:United States National Aeronautics and Space Administration