Signal Communication by Orbiting Relay Equipment; first communications satellite; transmitted taped messages for 13 days.

In August 1955 the Stewart Committee, having taken on the Pentagon's desire for the IGY effort not to affect either the Air Force Atlas ICBM or Army Jupiter IRBM programs, selected the Navy's Vanguard as the booster for America's first satellite.

Convair, however, saw a bright future for their Atlas rocket as a space launch vehicle. They made an unsolicited proposal before the Stewart Committee decision to the Air Force to use the three-engined Atlas C as an Orbital Research and Test Vehicle. This would boost a 230 kg satellite into orbit without the need for an upper stage. Nothing came of this proposal immediately.

On 1 February 1957 Air Force headquarters asked Schriever to provide a plan to fly a back-up scientific satellite for during the International Geophysical Year, in case Vanguard failed. The reply came a week later. $91 million would be required. But Atlas development was such that no launchings could be guaranteed before mid-1959. It was however possible, best case, that one or two launchings could be managed before the end of the IGY in 1958. The Air Force declined to spend the money.

The Soviet launch of Sputnik 1 in October 1957 had a political impact far beyond the loss of a few months in the Atlas operational date. Vanguard did indeed fail, and another Vanguard competitor, the Army's Redstone, managed to orbit a tiny satellite in January 1958. The Soviets launched the massive 1327-kg Sputnik 3 in May 1957, again humbling the Americans. The Convair Orbital Research and Test Vehicle concept was resurrected as Project Score, and Schriever was given funds to launch a satellite using an Atlas as soon as possible. A three-engined Atlas B launched the Score satellite into orbit in December 1958, doing something to restore US prestige. It remained attached to the Atlas, allowing the Americans to claim they had orbited a 4 metric ton satellite, although all but 70 kg of that was the Atlas itself.

Typical orbit: 185 km x 1484 km at 32 degrees inclination. Mass: 70 kg (154 lb).

• 1958 December 18 - Score - Launch Site: Cape Canaveral. Launch Complex: LC11. Launch Vehicle: Atlas. Mass: 70 kg (154 lb). Perigee: 185 km (114 mi). Apogee: 1,484 km (922 mi). Inclination: 32.30 deg. Period: 101.50 min.
  Signal Communication by Orbiting Relay Equipment; first commsat; transmitted taped messages for 13 days.