It may well be argued that NASA has become the world's premier agent for exploration, carrying on in "the new ocean" of outer space a long tradition of expanding the physical and mental boundaries of humanity.
The year 2008 will be a year of 50th anniversaries for space exploration. Following in the wake of Sputnik I and Sputnik II, on January 31, 1958 the United States launched Explorer 1.
A recent conference on the moons of Mars reminded me of the wonders that await us even in our own solar system.
Galileo represented a new phase in the study of the outer planets. Pioneer and Voyagers 1 and 2 together completed the preliminary reconnaissance of those gas giants, but Galileo undertook a much more systematic, in-depth and holistic analysis of the entire Jupiter system.
Originally planned to explore the gas giant planets and their satellites, the Voyager spacecraft have continued their journeys and are now the most distant human objects in the cosmos.