was extraordinarily time-sensitive, the designers of the system could not use the film-canister dropping system that had been pioneered by the Discoverer/Corona/SAMOS series of reconnaissance satellites. In that system, the cameras aboard the satellites used photographic film capsules that physically re-entered the atmosphere before being retrieved mid-air by a military airplane. The MIDAS satellites would instead have to transmit their warning signals earthward via radio waves. Actual infrared images would not be transmitted due to the limited RF channel capacity that was available then. Instead, the satellite would simply send radio messages that it had detected a suspected missile launch as well as the time and location of the launch. Multiple MIDAS satellites would be needed to provide round-the-clock coverage of the huge landmass of the Soviet Union. A booster rocket capable of sending a satellite into geostationary orbit had not yet been developed, and one or a few of these might not be able to cover all the possible ICBM launch sites within Russia, especially in the far north near the Arctic Circle. Satellites in polar orbits would be needed to detect launches from across the Soviet Union but due to the nature of the polar orbit, each would have only a brief period of time above the Soviet Union. As the planned capabilities of the satellite changed during the design process, so did the plans for their deployment. A plan completed in January 1959 recommended a constellation of twenty MIDAS satellites orbiting at an altitude of 1,000 miles while a revised plan, produced later that year, envisioned a constellation of twelve spacecraft at 2,000-mile altitudes. Implementing a complete system, estimated in 1959, was put at between $200 million and $600 million (equivalent to $ and $ in ). Because of this enormous cost and the fact that several "unanswered questions" remained, the scientific advisory council in charge of advising President Dwight D. Eisenhower on Early Warning systems recommended that a program of research be conducted but that final word on implementing a complete system be delayed for at least a year. In FY1959, ARPA spent $22.8 million (equivalent to $ in ) on MIDAS, and in FY1960, ARPA and the Air Force spent a combined sum of $94.9 million (equivalent to $ in ). Program summary and launch history The MIDAS program commenced on February 26, 1960 when MIDAS 1 lifted off on an Atlas-Agena A booster from