Abstract :
From the outset, proponents of space exploration have argued that it is justified because of its enhancement of national security, contribution to basic scientific knowledge, and potential for economic gain. Without reconnaisance satellites, they say, international tensions would mount. Scientists point to multitudes of discoveries about the universe, the solar system, the moon, the earth, and the human body that have resulted from space programs. But outside of communications, little economic gain has been realized directly from the first 25 years of space activity.