Luna E-6 No.5, sometimes identified by NASA as Luna 1964B, was a Soviet spacecraft which was lost in a launch failure in 1964. It was a 1,422-kilogram (3,135 lb) Luna E-6 spacecraft, the fifth of twelve to be launched, It was intended to be the first spacecraft to perform a soft landing on the Moon, a goal which would eventually be accomplished by the final E-6 spacecraft, Luna 9.
Luna E-6 No.5 was launched at 08:08:28 UTC on 20 April 1964, atop a Molniya-M 8K78M carrier rocket, flying from Site 1/5 at the Baikonur Cosmodrome. The power system on the upper stage malfunctioned 340 seconds into the flight, causing the engine to cut off before reaching orbit. The upper stage and spacecraft disintegrated upon reentry into the atmosphere shortly afterwards. Prior to the release of information about its mission, NASA correctly identified that it had been an attempt to land a spacecraft on the Moon.
Payloads are separated by bullets ( · ), launches by pipes ( | ). Manned flights are indicated in bold text. Uncatalogued launch failures are listed in italics. Payloads deployed from other spacecraft are denoted in brackets.