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the first U.S. attempt to obtain close-up images of the lunar surface
The Ranger spacecraft were designed to fly straight down towards the Moon and send images back until the moment of impact, to rough-land a seismometer capsule on the Moon, to collect gamma-ray data in flight, and to study radar reflectivity of the Lunar surface. All this was being done in order to "scout" locations for a planned manned landing on the Moon.
A total of nine Rangers were launched, beginning on August 23, 1961, five of which were successful. The last one was launched on March 24, 1965.
The basic spacecraft was 3.1 m high and consisted of a lunar capsule 65 cm in diameter, a mono-propellant mid-course motor, a 5,080-pound thrust retrorocket, and a gold- and chrome-plated hexagonal base 1.5 m in diameter. A large high-gain dish antenna was attached to the base. Two wing-like solar panels, each 5.2 m across, were attached to the base and deployed early in the flight. Power was generated by 8,680 solar cells.
Each Ranger spacecraft had 6 cameras on board, each of which provided better resolution than was available from Earth-based views by a factor of 1000. Other apparatus carried by the spacecraft were a gamma-ray spectrometer, a radar altimeter, and a seismometer to be rough-landed on the Lunar surface.
The first image below was taken by Ranger 7 about 17 minutes before impact; the second was taken immediately before impact.
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This page was last updated on 09/18/2018.