- Ranger 2
Ranger 2 was a flight test of the Ranger spacecraft system of the
NASA Ranger programdesigned for future lunar and interplanetary missions. Ranger 2 was designed to test various systems for future explorationand to conduct scientific observations of cosmic rays, magnetic fields, radiation, dust particles, and a possible hydrogen gas "tail" trailing the Earth.
Ranger 2 was of the Ranger Block 1 design and was almost identical to
Ranger 1. The spacecraft consisted of a hexagonalbase 1.5 m across upon which was mounted a cone-shaped 4 m high tower of aluminum struts and braces. Two solar panel wings measuring 5.2 m from tip to tip extended from the base. A high-gain directional dish antennawas attached to the bottom of the base. Spacecraft experiments and other equipment were mounted on the base and tower. Instruments aboard the spacecraft included a Lyman-alpha telescope, a rubidium-vapor magnetometer, electrostaticanalyzers, medium-energy-range particle detectors, two triple coincidence telescopes, a cosmic-ray integrating ionization chamber, cosmic dustdetectors, and scintillation counters.
communications systemincluded the high gain antenna and an omni-directional medium gain antenna and two transmitters at approximately 960 MHz, one with 0.25 W power output and the other with 3 W power output. Power was to be furnished by 8680 solar cellson the two panels, a 53.5 kg silver-zinc battery, and smaller batteries on some of the experiments. Attitude control was provided by a solid state timing controller, Sunand Earthsensors, gyroscopes, and pitch and roll jets. The temperature was controlled passively by gold plating, white paint, and polished aluminumsurfaces.
The spacecraft was launched into a low Earth
parking orbit, but an inoperative roll gyro prevented Agena restart. The spacecraft could not be put into its planned deep space trajectory, resulting in Ranger 2 being stranded in low earth orbit upon separation from the Agena stage. The orbit decayed and the spacecraft reentered Earth's atmosphere on November 20, 1961.
* [http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19780007206_1978007206.pdf Lunar impact: A history of Project Ranger (PDF) 1977]
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