Luna 9

{{short description|1966 uncrewed space mission of the Soviet Union's Luna programme}}

{{Infobox spaceflight

| name = Luna 9

| image = Luna 9 Musee du Bourget P1010505.JPG

| image_caption = A replica of Luna 9 on display in the Museum of Air and Space Paris, Le Bourget.

| mission_type = Lunar lander

| operator = Soviet space program

| COSPAR_ID = 1966-006A

| SATCAT = 01954

| mission_duration = 6 days, 11 hours, 10 minutes

| spacecraft_type = Ye-6

| manufacturer = GSMZ Lavochkin

| dry_mass =

| launch_mass = 1583.7 kg{{sfn|Siddiqi|2018|p=55}}

| landing_mass = 99 kg

| dimensions =

| power =

| launch_date = 31 January 1966, 11:41:37 UTC{{sfn|Siddiqi|2018|p=55}}

| launch_rocket = Molniya-M 8K78M s/n 103-32

| launch_site = Baikonur, Site 31/6

| last_contact = 6 February 1966, 22:55 GMT

| orbit_epoch = 31 January 1966

| orbit_reference = Geocentric

| orbit_regime = Highly elliptical

| orbit_periapsis = 220 km

| orbit_apoapsis = 500000 km

| orbit_inclination = 51.8°

| orbit_period = 14.96 days

| apsis = gee

|interplanetary =

{{Infobox spaceflight/IP

|type = lander

|object = Lunar

|arrival_date = 3 February 1966, 18:45:30 GMT

|location = {{Lunar coords and quad cat|7.08|N|64.37|W}} or {{Lunar coords and quad cat|7.13|N|64.37|W}}{{Cite web|url=https://nssdc.gsfc.nasa.gov/planetary/lunar/lunar_artifact_impacts.html|title = Table of Anthropogenic Impacts and Spacecraft on the Moon}}

}}

| programme = Luna programme

| previous_mission = Luna 8

| next_mission = Kosmos 111

}}

Luna 9 (Луна-9), internal designation Ye-6 No.13, was an uncrewed space mission of the Soviet Union's Luna programme. On 3 February 1966, the Luna 9 spacecraft became the first spacecraft to achieve a soft landing on the Moon and return imagery from its surface.{{cite book |last1=Reichl |first1=Eugen |title=The Soviet Space Program The Lunar Years: 1959-1976 |date=2019 |isbn=978-0-7643-5675-9 |pages=86-87 |url=https://www.amazon.com.au/dp/0764356755 |access-date=27 September 2024}}

Spacecraft

The spacecraft carrying on top the lander capsule, weighed together 1538 kg and was 2.7 meters tall. It commenced the main descent, shortly before its controlled impact it ejected the lander capsule.

The lander had a mass of {{convert|99|kg|lb}} and consisted of a spheroid Automatic Lunar Station (ALS) capsule measuring {{convert|58|cm|in}}.{{cite web | title=NSSDCA – Spacecraft – Details | website=NASA | date=2023-10-18 | url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1966-006A | access-date=2023-10-19}} It used a landing bag to survive the impact speed of over {{convert|54|km/h|mph}}.{{cite web|url=http://www.astronautix.com/craft/lunae6.htm|title=Luna E-6|website=astronautix.com|access-date=25 November 2020|url-status=dead|archive-url=https://web.archive.org/web/20160315130827/http://www.astronautix.com/craft/lunae6.htm|archive-date=15 March 2016}} 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 spacecraft was developed in the design bureau then known as OKB-1, under Chief Designer Sergei Korolev (who had died before the launch). The first 11 Luna missions were unsuccessful for a variety of reasons. At that time the project was transferred to Lavochkin design bureau since OKB-1 was busy with a human expedition to the Moon. Luna 9 was the twelfth attempt at a soft-landing by the Soviet Union; it was also the first successful deep space probe built by the Lavochkin design bureau, which ultimately would design and build almost all Soviet (later Russian) lunar and interplanetary spacecraft. {{cite book|url=https://www.nasa.gov/sites/default/files/atoms/files/beyond-earth-tagged.pdf |archive-url=https://web.archive.org/web/20190424211923/https://www.nasa.gov/sites/default/files/atoms/files/beyond-earth-tagged.pdf |archive-date=2019-04-24 |url-status=live|title=Beyond Earth: A Chronicle of Deep Space Exploration, 1958–2016|pages=1–2|last1=Siddiqi|first1=Asif A.|lccn=2017059404|isbn=9781626830424|publisher=NASA History Program Office|edition=second |year=2018|id=SP2018-4041|series=The NASA history series|location=Washington, D.C.}}

Launch and translunar coast

Luna 9 was launched by a Molniya-M rocket, serial number 103-32, flying from Site 31/6 at the Baikonur Cosmodrome in the Kazakh Soviet Socialist Republic. Liftoff took place at 11:41:37 GMT on 31 January 1966. The first three stages of the four-stage carrier rocket injected the payload and fourth stage into low Earth orbit, at an altitude of {{convert|168|by|219|km|mi}} and an inclination of 51.8°.{{cite web|url=http://planet4589.org/space/log/satcat.txt|title=Satellite Catalog|first=Jonathan |last=McDowell|work=Jonathan's Space Page|access-date=14 August 2013}} The fourth stage, a Blok-L, then fired to raise the perigee of the orbit to a new apogee approximately {{convert|500000|km}}, before deploying Luna 9 into a highly elliptical geocentric orbit.

For thermal control, the spacecraft then spun itself up to 0.67 rpm using nitrogen jets. On 1 February at 19:29 GMT, a mid-course correction took place involving a 48-second burn and resulting in a delta-v of {{convert|71.2|m/s|ft/s}}.{{cite web|url=https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1966-006A|title=NASA-NSSDC-Spacecraft-Details|publisher=NASA|access-date=4 April 2013}}

Descent and landing

{{overlay

|image = Luna 8 and 9 locations Planitia Descensus 3214 med.jpg

|float = left

|width = 300

|height = 205

|legend1title = Oblique LO3 view of Planitia Descensus

|legend1start = 8

|overlay8 = Luna 8 (Crashed)

|overlay8top = 57

|overlay8left = 234

|overlay8link = Luna 8

|overlay8tip = Luna 8 (Crash Site)

|overlay8colour = yellow

|overlay9 = Luna 9

|overlay9top = 133

|overlay9left = 52

|overlay9link = Luna 9

|overlay9tip = Luna 9 (Landing Site)

|overlay9colour = yellow

}}

At an altitude of {{convert|8300|km|mi}} from the Moon, the spacecraft was oriented for the firing of its retrorockets and its spin was stopped in preparation for landing. From this moment the orientation of the spacecraft was supported by measurements of directions to the Sun and the Earth using an optomechanical system. At {{convert|75|km|mi}} above the lunar surface, the radar altimeter triggered the jettison of the side modules, the inflation of the airbags and the firing of the retro rockets. At {{convert|250|m|ft}} from the surface, the main retrorocket was turned off by the integrator of an acceleration having reached the planned velocity of the braking manoeuver. The four outrigger engines were used to slow the craft. About {{convert|5|m|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 and its landing airbag being inflated. The capsule landed at {{convert|22|km/h|mph m/s}}.

The capsule bounced several times before coming to rest in Oceanus Procellarum west of Reiner and Marius craters at approximately 7.08 N, 64.37 W (other sources indicate {{Lunar coords and quad cat|7.13|N|64.37|W}}{{Cite web|url=https://nssdc.gsfc.nasa.gov/planetary/lunar/lunar_artifact_impacts.html|title = Table of Anthropogenic Impacts and Spacecraft on the Moon}}) on 3 February 1966 at 18:45:30 GMT.

Surface operations

file:Luna-9 model.jpg

file:First Photo from the Surface of the Moon.jpg

Approximately 250 seconds after landing in the Oceanus Procellarum, four petals that covered the top half of the spacecraft opened outward for increased stability. Seven hours after (to allow for the Sun to climb to 7° elevation) the probe began sending the first of nine images (including five panoramas) of the surface of the Moon. Seven radio sessions with a total of 8 hours and 5 minutes were transmitted, as well as a series of three TV pictures. After assembly the photographs gave a panoramic view of the immediate lunar surface, comprising views of nearby rocks and of the horizon, {{convert|1.4|km|mi}} away.

The pictures from Luna 9 were not released immediately by the Soviet authorities, but scientists at Jodrell Bank Observatory in England, which was monitoring the craft, noticed that the signal format used was identical to the internationally agreed Radiofax 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.Daily Express [http://proftimobrien.com/wp-content/uploads/2013/12/Luna9-DailyExpress.jpg front page Saturday February 5 1966] The BBC 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 Observatory.[http://news.bbc.co.uk/onthisday/hi/dates/stories/february/3/newsid_4063000/4063471.stm BBC On This Day | 3 | 1966: Soviets land probe on Moon]

The radiation detector, the only dedicated scientific instrument on board, measured dosage of 30 millirads (0.3 milligrays) per day.[https://nssdc.gsfc.nasa.gov/nmc/experiment/display.action?id=1966-006A-02 NSSDCA ID: 1966-006A-02] The mission also determined that a spacecraft would not sink into the lunar dust; that the ground could support a lander. The last contact with the spacecraft was at 22:55 GMT on 6 February 1966.

Models and displays

Detailed Luna 9 models are on display at the Memorial Museum of Cosmonautics, Tsiolkovsky State Museum of the History of Cosmonautics, Museum of Cosmonautics and Rocket Technology, Museum of Air and Space Paris and other locations.

File:Luna-9 (Memorial Museum of Astronautics).JPG|Luna 9 mockup (1:1) at the Memorial Museum of Cosmonautics.

File:FP2A3144 (23497692808).jpg|Luna-9 descent capsule at the Memorial Museum of Cosmonautics.

File:Luna 9 Space Probe.jpg|Luna 9 on display at the Tsiolkovsky State Museum of the History of Cosmonautics.

File:Luna-9 Space Probe Descent Capsule.jpg|Luna-9 descent capsule at the Tsiolkovsky State Museum of the History of Cosmonautics.

File:Onboard container of the Luna-9 automatic control system 1.jpg| Onboard container of the automatic control system "Luna-9", Museum of the History of Cosmonautics.

File:Модель автоматической станции Луна-9 с посадочной ступенью 1.jpg|Luna 9 model at the Museum of Cosmonautics and Rocket Technology.

Stamps

The successful Luna 9 landing was commemorated on stamps.

File:The Soviet Union 1966 CPA 3314 stamp (2851 Overprinted in Silver 'Luna 9 - on the Moon! 3.2. 1966').png|USSR stamp "Luna 9"–on the Moon! 3.2. 1966.

File:The Soviet Union 1966 CPA 3315 stamp (Luna 9 Flight Scheme (Start 01.31, Soft Landing 02.03)).jpg|USSR stamp "Luna 9" Flight Scheme (Start 01.31, Soft Landing 02.03)

File:The Soviet Union 1966 CPA 3316 stamp (Arms of USSR and Pennant Sent to Moon by Luna 9).png|USSR stamp Arms of USSR and Pennant Sent to Moon by "Luna 9".

File:The Soviet Union 1966 CPA 3317 stamp (Luna 9 on Moon's Surface and 1st Television Program of Moon Pictures on February 4).jpg|USSR stamp "Luna 9" on Moon's Surface and 1st Television Program of Moon Pictures on 4 February

File:1966 CPA 3415.jpg|Stamp of the Soviet Union, 1966

File:Stamps of Germany (DDR) 1966, MiNr 1168.jpg|GDR stamp, 1966