Since leaving NASA fifteen years earlier, Dr. Paine had been a vocal spokesman for an expansive future of Space exploration. The National Commission on Space took most of a year to prepare its report, conducting public hearings throughout the United States. The Commission report, "Pioneering the Space Frontier", was published in May 1986. It espoused "a pioneering mission for 21st-century America... to lead the exploration and development of the space frontier, advancing science, technology, and enterprise, and building institutions and systems that make accessible vast new resources and support human settlements beyond Earth orbit, from the highlands of the Moon to the plains of Mars." The report also contained a "Declaration for Space" that included a rationale for exploring and settling the solar system and outlined a long-range space program for the United States.