Ranger 4

Ranger 4
Ranger 4
Mission typeLunar impactor
OperatorNASA
Harvard designation1962 Mu 1
COSPAR ID1962-012A Edit this at Wikidata
SATCAT no.280
Mission duration10 hours (operational)
64 hours (to impact)
Spacecraft properties
ManufacturerJet Propulsion Laboratory
Launch mass331.1 kg (730 lb)
Dimensions1.52 m × 2.51 m (5.0 ft × 8.2 ft)
Power135 W
Start of mission
Launch dateApril 23, 1962, 20:50:00 (1962-04-23UTC20:50Z) UTC
RocketAtlas LV-3 Agena-B
Launch siteCape Canaveral LC-12
Lunar impactor
Impact dateApril 26, 1962, 12:49:53 (1962-04-26UTC12:49:54Z) UTC
Failed before impact
Impact site15°30′S 130°42′W / 15.5°S 130.7°W / -15.5; -130.7

Ranger 4 was a spacecraft of the Ranger program, launched in 1962. It was designed to transmit pictures of the lunar surface to Earth stations during a period of 10 minutes of flight prior to crashing upon the Moon, to rough-land a seismometer capsule on the Moon, to collect gamma-ray data in flight, to study radar reflectivity of the lunar surface, and to continue testing of the Ranger program for development of lunar and interplanetary spacecraft.

An onboard computer failure caused failure of the deployment of the solar panels and navigation systems; as a result the spacecraft crashed on the far side of the Moon without returning any scientific data. It was the first spacecraft of the United States to reach another celestial body[2][3][4] and the first of any nation to reach the surface of the far side of the Moon.

  1. ^ NASA, Goddard Space Flight Center. "Experiments on Ranger 4". NSSDC Master Catalog. Retrieved December 3, 2022.
  2. ^ "National Space Science Data Center - Ranger 4". National Air and Space Administration. Retrieved 19 June 2012.
  3. ^ "Ranger 4 crashes on Moon". Lewiston Morning Tribune. (Idaho). Associated Press. April 27, 1962. p. 1.
  4. ^ "Ranger-4 hits moon in new space triumph". Bend Bulletin. (Oregon). UPI. April 26, 1962. p. 1.