Luna 9 (E-6 series, N.13) was an unmanned space mission of the Soviet Union's Luna program. On February 3, 1966 the Luna 9 spacecraft was the first spacecraft to achieve a soft landing on the Moon, or any planetary body other than Earth, and to transmit photographic data to Earth.

The automatic lunar station that achieved the landing weighed 99 kilograms (220 lb). It used a landing bag to survive the impact speed of 22 kilometres per hour (14 mph). It was a hermetically sealed container with radio equipment, a program timing device, heat control systems, scientific apparatus, power sources, and a television system. The Luna 9 payload was carried to Earth orbit by a 3-stage Molniya SL-6/A-2-e rocket, and then sent toward the Moon by the fourth stage.

The fourth stage separated from the payload on January 31st. The spacecraft then spun itself up to 0.67 rpm using nitrogen jets. On February 1st at 19:29 UT (22:29 Moscow time) a mid-course correction took place involving a 48 second burn and resulting in a delta-V of 71.2 metre per second (234 ft/s).

At an altitude of 8,300 kilometres (5,200 mi) from the moon, the spacecraft was oriented for the firing of its retrorockets and its spin was stopped in preparation for landing. At 25 kilometres (16 mi) above the lunar surface, the radar altimeter triggered the jettison of the side modules, the inflation of the air bags and the firing of the retro rockets. At 250 metres (820 ft) from the surface the main retrorocket was turned off and the four outrigger engines were used to slow the craft. Approximately 5 metres (16 ft) above the lunar surface, a contact sensor touched the ground triggering the engines to be shut down and the landing capsule to be ejected. The craft landed at 22 kilometres per hour (14 mph)

The spacecraft bounced several times before coming to rest in Oceanus Procellarum west of Reiner and Marius craters at approximately 7.08 N, 64.37 W on February 3, 1966 at 18:45:30 UT (21:45:30 Moscow time).

Approximately 250 seconds after landing in the Oceanus Procellarum on February 3, the four petals which covered the top half of the spacecraft opened outward and stabilized it on the lunar surface. Spring-controlled antennas assumed operating positions, and the television camera rotating mirror system, which operated by revolving and tilting, began a photographic survey of the lunar environment. Seven radio sessions, totaling 8 hours and 5 minutes, were transmitted, as were three series of TV pictures.

When assembled, the photographs provided a panoramic view of the nearby lunar surface. The pictures included views of nearby rocks and of the horizon, 1.4 kilometres (0.87 mi) away.

The pictures from Luna 9 were not released immediately by the Soviet authorities. Instead, the Jodrell Bank Observatory in England, which was monitoring the craft, noticed that the signal format used was identical to the internationally-agreed system used by newspapers for transmitting pictures. The Daily Express rushed a suitable receiver to the Observatory and the pictures from Luna 9 were decoded and published worldwide. The BBC News speculated that the spacecraft's designers deliberately fitted the probe with equipment conforming to the standard, to enable reception of the pictures by Jodrell Bank.

With this mission, the Soviets accomplished a first in the Space Race: the first survivable landing of a man-made object on another celestial body. Luna 9 was the twelfth attempt at a soft-landing by the Soviets; it was also the first deep space probe built by the Lavochkin design bureau, which ultimately would design and build almost all Soviet (later Russian) lunar and interplanetary spacecraft. All operations prior to landing occurred without fault, and the 58 centimetres (23 in) spheroid ALS capsule landed on the Moon at 18:45:30 UT on February 3, 1966 west of the craters Reiner and Marius in the Ocean of Storms (at 7°8' north latitude and 64°22' west longitude). Approximately five minutes after touchdown, Luna 9 began transmitting data to Earth, but it was seven hours (after the Sun had climbed to 7° elevation) before the probe began sending the first of nine images (including five panoramas) of the surface of the Moon. These were the first images sent from the surface of another planetary body.

The radiation detector, the only scientific instrument on board, measured a dosage of 30 millirads (0.3 milligrays) per day. Perhaps the most important discovery of the mission was determining that a foreign object would not simply sink into the lunar dust, that is, that the ground could support a heavy lander. Last contact with the spacecraft was at 22:55 UT on February 6, 1966.

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