Ranger 4 crash lands on the moon, April 26, 1962
The Ranger 4 spacecraft was designed to crash-land on the moon after capturing a series of images of the lunar surface on its approach. The mission also included rough-landing a seismometer capsule, collecting gamma-ray data in flight, and studying radar reflectivity of the lunar surface.
However, an onboard computer failure caused the spacecraft to crash on the far side of the moon without returning any scientific data. Scientists confirmed it reached the moon by tracking the battery-powered 50 mW transmitter in the lunar landing capsule. Ranger 4 impacted the far side of the moon at 9600 km/hr at 12:49:53 UT on April 26, after 64 hours of flight.
The Ranger 4 mission may have failed, but it marked the first time the Atlas-Agena launch system and Ranger spacecraft performed together without fault.
The Ranger 3 previously attempted the same mission but missed the moon by 22,000 miles after a series of malfunctions. NASA finally succeeded in getting close images of the lunar surface from the Ranger 7. In total, the Ranger program launched nine spacecraft to explore the moon, costing $170 million in research, development, and support.
- Luna 2 reaches the moon, September 14, 1959
- Ranger 9 launches for lunar impact, March 21, 1965
- Apollo 11 makes 1st manned landing on the moon, July 20, 1969
- Project Diana bounces radio waves off moon, January 10, 1946
- Computers on the moon
- Slideshow: NASA says “Hands off our stuff on the moon!”
- NASA: Revealing the unknown to benefit all humankind
For more moments in tech history, see this blog. EDN strives to be historically accurate with these postings. Should you see an error, please notify us.
Editor's note: This article was originally posted on April 25, 2013 and edited on April 26, 2017.