The Block II of Ranger’s seismic packages represented scientists’ earliest attempts to measure the seismic properties of the Moon. Rangers 3, 4, and 5 hoisted a seismometer within a balsawood impact-limiter at their apex, a device designed at the California Institute of Technology. During Ranger’s flight, the lunar seismometer was programmed to separate from the main capsule, with the seismometer breaking free from the rocket as it approached close enough to the Moon to be pulled in by gravity. The balsawood case would strike the surface at 150 MPH, at which point the seismometer could begin its measurements. The device floated in an oil film within the balsawood shield and was meant to transmit data for 30 days. Though it was designed to withstand a 200 MPH impact, all three attempts to crash on the Moon with a functioning seismic device failed. Rangers 3 and 5 missed the Moon due a guidance systems and electrical failure, respectively; Ranger 4 successfully hit the Moon but the computer-timer failed, thus preventing any data collection.
NASA's Marshall Space Flight Center transferred this to the Museum in 1972.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.
United States of America
SPACECRAFT-Uncrewed-Guidance & Control
NASA Marshall Space Flight Center
Storage: 45.72 x 187.96 x 44.45cm (1ft 6in. x 6ft 2in. x 1ft 5 1/2in.)
HAZMAT: Cadmium Plating, Magnesium
Aluminum, Steel, Stainless Steel, Rubber (silicone), Gold Plating, Plastic, Nylon, Silver, Epoxy
A19731641000
Transferred from NASA Marshall Space Flight Center
National Air and Space Museum
Usage conditions apply
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