Destination Mankind (1972)

[n2doc]

By David S. F. Portree

In May 1972, Krafft Ehricke, Executive Advisor in the Space Division of North American Rockwell Corporation, proposed that Apollo 17, scheduled for the end of 1972, be postponed until the U.S. Bicentennial in 1976 and dispatched to a new destination: a geosynchronous orbit (GSO) 22,300 miles above the Earth. An object in a GSO requires one day to complete one revolution of the Earth. Since Earth revolves in one day, an object in equatorial GSO appears to hang over one spot on the equator.

“The mission into geosynchronous orbit,” Ehricke wrote, would provide “additional return on America’s investment in Apollo” by dramatizing “the usefulness of manned orbital activities.” He added that his proposal, which he dubbed Destination Mankind, “would inspire many, as did the lunar missions before it, but in a different, perhaps more direct manner, because of its greater relevance to some of the most pressing problems of our time.”

Ehricke described a representative 12-day Destination Mankind mission. Reaching GSO would require about as much energy as reaching lunar orbit. The three-stage Destination Mankind Apollo Saturn V rocket would lift off from Launch Complex 39 at Kennedy Space Center, Florida, at about 8:30 p.m. local time. Following first and second stage operation, the S-IVB third stage would fire briefly to place itself, the Apollo Command and Service Module (CSM), and a Payload Module (PM) into 100-nautical-mile parking orbit. One orbital revolution (about 90 minutes) later, the S-IVB would ignite again for Transynchronous Injection (TSI). After S-IVB shutdown, the astronauts would separate the CSM and turn it 180° to dock with the PM, which would be attached to the top of the S-IVB in place of the Apollo Lunar Module (LM). They would then extract the PM, maneuver away from the S-IVB, and settle in for the 5.2-hour coast to GSO.

The Destination Mankind CSM would ignite its Service Propulsion System (SPS) engine to enter a GSO at 31° east longitude. This would place it over the equatorial nation of Uganda – if the CSM entered an equatorial GSO. The mission’s GSO would, however, be inclined 28.5° relative to Earth’s equator, so the CSM would oscillate between 28.5° south latitude (over South Africa’s east coast) and 28.5° north latitude (southwest of Cairo) and back every 24 hours. The CSM would reach its southern limit at 10 a.m. local time and its northern limit at 10 p.m. local time. This 57°-long stretch of the 31° east longitude line would constitute Destination Mankind’s “Afro-Eurasian Station.” (The Meteosat-2 image at the top of this post approximates the view from Destination Mankind’s Afro-Eurasian Station)


more http://www.wired.com/wiredscience/2012/03/destination-mankind-1972/