Luna 5

From Wikipedia, the free encyclopedia

Orbital elements
Luna 5

Organization	Soviet Union
Major contractors	OKB-1
Mission type	Planetary Science Lunar landing
Launch	May 9, 1965 at 07:55:00 UTC
Launch vehicle	Molniya 8K78M (4-Stage R-7 / SS-6)
Mission highlight	Lunar impact (see below)
Mission duration	3 days
Mass	1,474 kg
NSSDC ID	1965-036A
Webpage	NASA NSSDC Master Catalog
Satellite of	Moon
Orbits	none
Lunar Landing	Lunar impact May 12, 1965, 19:10 UTC
Landing coordinates	31° S 8° W
Instruments
Close-Up Lunar Surface Photography

Luna 5 (E-6 series) was an unmanned space mission of the Luna program, also called Lunik 5. It was designed to continue investigations of a lunar soft landing. The retrorocket system failed, and the spacecraft impacted the lunar surface at the Sea of Clouds.

In May 1965, Luna 5 became the first Soviet probe to head for the Moon in two years. Between it and the previous Luna 4, there were three launch failures (Luna 1964A on March 21, 1964; Luna 1964B on April 20, 1964; and Zond 1964A on April 10, 1965) and one partial failure (Cosmos 60, launched on March 12, 1965, which reached Earth orbit but failed to leave for the Moon).

Following the midcourse correction on May 10, the spacecraft began spinning around its main axis due to a problem in a flotation gyroscope in the I-100 guidance system unit. A subsequent attempt to fire the main engine failed because of ground control error, and the engine never fired. After loss of control as a result of the gyroscope problem, Luna 5 crashed. Landing coordinates were 31° south latitude and 8° west longitude. It was the second Soviet spacecraft to "land" on the Moon (following Luna 2 in 1959).