Mission type Lunar lander COSPAR ID 1967-068A Launch site Cape Canaveral LC-36A Launch date 14 July 1967 Manufacturer Hughes Aircraft Company | Operator NASA SATCAT no. 02875 Dry mass 282 kg Rocket Atlas-Centaur | |
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Mission duration 65 hours
Failed to land Similar Surveyor 5, Surveyor 6, Surveyor 7, Surveyor 2, Surveyor 3 | ||
Surveyor 4 was the fourth lunar lander in the American unmanned Surveyor program sent to explore the surface of the Moon. This spacecraft crashed after an otherwise flawless mission; telemetry contact was lost 2.5 minutes before touchdown. The planned landing target was Sinus Medii (Central Bay) at 0.4° north latitude and 1.33° west longitude.
Equipment
This spacecraft was the fourth in a series designed to achieve a soft landing on the Moon and to return photography of the lunar surface for determining characteristics of the lunar terrain for Apollo lunar landing missions. Equipment on board included a television camera and auxiliary mirrors, a soil mechanics surface sampler, strain gauges on the spacecraft landing legs, and numerous engineering sensors. Like Surveyor 3, Surveyor 4 was also equipped with a surface claw (with a magnet in the claw) to detect and measure ferrous elements in the lunar surface.
After a flawless flight to the Moon, radio signals from the spacecraft ceased during the terminal-descent phase at 02:03 UT on 17 July 1967, approximately 2.5 minutes before touchdown. Contact with the spacecraft was never reestablished, and the mission was unsuccessful. The solid-fuel retrorocket may have exploded near the end of its scheduled burn.