Explorer S-55 (satellite)

Explorer S-55 was an American satellite launched by NASA on 30 June 1961, as part of the Explorer program. Explorer S-55, was launched using a Scout X-1 launch vehicle from the Wallops Flight Facility (WFF). Its mission was to evaluate the launch vehicle and investigate micrometeoroid impact and penetration. The mission failed because the third stage failed to ignite and the spacecraft did not achieve orbit.

Explorer S-55

Explorer S-55 satellite
Names	Explorer S-55 NASA S-55
Mission type	Micrometeoroid research
Operator	NASA
Mission duration	Failed to orbit
Spacecraft properties
Spacecraft	Explorer S-55
Spacecraft type	Science Explorer
Bus	S-55
Manufacturer	Goddard Space Flight Center
Launch mass	86 kg (190 lb)
Dimensions	1.93 × 0.61 m (6 ft 4 in × 2 ft 0 in) cylinder
Power	Solar cells and nickel-cadmium batteries
Start of mission
Launch date	30 June 1961, 17:09 GMT
Rocket	Scout X-1 (ST-5)
Launch site	Wallops Flight Facility, LA-3
Contractor	Vought
End of mission
Destroyed	Failed to orbit
Orbital parameters
Reference system	Geocentric orbit (planned)
Regime	Low Earth orbit
Instruments
Instruments Cadmium Sulfide Cell Micrometeorite Detector Copper Wire Micrometeroite Detector Pressurized Cell Micrometeorite Detector Impact Detection Grid Detectors
Explorer program

Mission

The objectives of the flight were to test vehicle performance and guidance and to investigate the nature and effects of micrometeoroids on the spacecraft systems. The scientific instrumentation consisted of cadmium sulfide-cell, wire-grid, piezoelectric, pressurized-cell and foil-type micrometeoroid detectors.

Spacecraft

The spacecraft was a 1.93 m × 0.61 m (6 ft 4 in × 2 ft 0 in) cylinder. Weighing 86 kg (190 lb), including its fourth stage and transition section, its objective was to test the performance of a Scout launch vehicle and its guidance system and to investigate the nature and effects of space flight on micrometeoroids. Its payload was a 1.93 × 0.61 m (6 ft 4 in × 2 ft 0 in) cylinder, almost covered by five types of micometeoroid impact detectors, two transmitters, solar cells and nickel-cadmium batteries.

Launch

Explorer S-55 was launched on 30 June 1961, at 17:09 GMT, in using a Scout X-1 launch vehicle. The mission failed because the third stage failed to ignite and the spacecraft did not achieve orbit.

See also

Explorer 13