The Soviet Luna Program and Russia's Luna 25

Between 1958 and 1976, the Soviet Union launched a total of 44 unmanned Luna spacecraft to the Moon, including impactors, fly-bys, soft landers, orbiters, rovers, and sample return missions. Of these, fifteen were considered successes. Only partial or complete successes were given the “Luna” designation, with launch failures usually unacknowledged and failures in Earth orbit receiving a catch-all “Kosmos” number. Luna spacecraft achieved a number of “firsts” including the first spacecraft to enter a heliocentric orbit, first lunar impact, first photos of the far side of the Moon, first soft landing on the Moon, first robotic sample return from the Moon (but after the Apollo 11 manned landing and return), and first robotic rover on the Moon (but after Apollo 15–17’s manned rovers).

The last Soviet Moon flight was Luna 24 in 1976. Forty-seven years later, Russia has launched Luna 25 to a crater near the lunar south pole. This probe has no common heritage with the Soviet Luna spacecraft, and represents the beginning of a new Russian lunar exploration project.

At this writing (2023-08-17), Luna 25 is expected to land on 2023-08-21.


Perhaps the moon will look a lot like Kiev.


Overall success rates: 34% (Luna) vs. 60% (Apollo)

I’ve searched for references for the likely costs of the Luna program unsuccessfully. I’m curious if any cost comparisons are out there. A CIA report from 1970s includes this chart, which ballparks 1960-1970 costs to around $40B 1968 dollars. But that would likely include Luna + all the other programs the USSR had under the space “umbrella”

In comparison, Apollo + Mercury + Gemini is supposed to have cost only $28B (source)

Luna 25 has entered orbit around the Moon and on 2023-08-17 returned its first image of the lunar surface from orbit. The above image, posted on Telegram, shows far side crater Zeeman, located at 75° south latitude.

Here is the Roscosmos announcement accompanying the photo, translated from Russian by Google Translate.

An automatic station flying in a circular orbit of an artificial satellite of the Moon took pictures of the lunar surface with television cameras of the STS-L complex.

The picture shows the south polar crater Zeeman on the far side of the Moon. The coordinates of the center of the crater correspond to 75 degrees south latitude and 135 degrees west longitude.

Invisible from Earth, the Zeeman crater is a unique object on the lunar surface and is of great interest to researchers — the height of the shaft surrounding it reaches 8 kilometers above the surface of a relatively flat bottom.

The resulting images significantly complement the currently available information about this crater. The world’s first image of the far side of the moon was obtained in October 1959 by the Soviet automatic station “Luna-3”.

“Luna-25” carried out observations with the help of ADRON-LR and PmL, ARIES-L instruments. Fluxes of gamma rays and neutrons from the lunar surface are measured, and the parameters of the circumlunar space plasma and gas and dust exosphere in the circumlunar orbit are also obtained.

Here is a synthetic view of Zeeman crater from Fourmilab’s Earth and Moon Viewer, using NASA Lunar Reconnaissance Orbiter imagery.


This image shows the horizon-to-horizon view from a spacecraft 500 km above the lunar surface. Zeeman is the crater at the centre, with the features that appear near the top centre of the Luna 25 image toward the 7 o’clock position along the crater wall. The terminator (day/night division) has been suppressed in this image.


In a 1990 interview with the British Interplanetary Society’s Spaceflight magazine, Vasily Mishin, chief of the Soviet lunar program, who took charge after the death of Sergei Korolev in 1966, estimated the total expenditure on the Soviet manned lunar project (N1/L3/L1) at US$ 4.5 billion, compared to his estimate of U.S. expenditures on Apollo of US$ 24 billion, and attributed its failure to under-investment which, in particular, precluded the extensive ground testing of components which NASA performed in development of the Saturn V and Apollo spacecraft.

This is consistent with the view of historian Asif A. Siddiqi in his NASA history publication, Challenge to Apollo, adding that the Soviets started late in getting serious about manned lunar landing and wasted scarce funds on competitive duplicate projects and squabbles among design bureaux.

Soviet rocket engineer Boris Chertok’s insider account of the Soviet lunar program in Rockets and People, Vol. 4, originally published in Russian in 1991, then in an annotated English translation by NASA in 2011, confirms this view and documents in detail how the Soviet program operated on shoestring budgets and cut corners trying to meet propaganda goals set by politicians and bureaucrats. While Apollo was an exemplar of government central planning in an at-any-cost crash program, the Soviet program was nothing of the kind (as I wrote in my review) “full of the kind of squabbling, turf wars, and duplicative competitive efforts which Marxists decry as flaws of the free market.” Further, “the Soviets were acutely aware of this in 1968. In chapter 9, Chertok recounts a Central Committee meeting in which Minister of Defence Dmitriy Ustinov remarked:”

…the Americans have borrowed our basic method of operation—plan-based management and networked schedules. They have passed us in management and planning methods—they announce a launch preparation schedule in advance and strictly adhere to it. In essence, they have put into effect the principle of democratic centralism—free discussion followed by the strictest discipline during implementation.


Thank you for the valuable pointers. Chertok had a very adventurous long life.


MOSCOW, August 19. /TASS/. After a command was issued to the probe Luna-25 for entering the pre-landing orbit an abnormal situation occurred, the space corporation Roscosmos told the media.

“Today, in accordance with the flight program of the Luna-25 probe, at 2:10 p.m. Moscow time, a command was issued to the probe to enter the pre-landing orbit. During the operation an emergency occurred on the space probe that did not allow it to perform the maneuver in accordance with the required parameters,” Roscosmos said.

At present specialists of the command and control team are analyzing the situation.


On 2023-08-20 at 08:47 UTC, Roscosmos posted the following to their Telegram account.


Here is Google Translate’s English rendering.

On August 19, in accordance with the flight program of the Luna-25 spacecraft, an impulse was provided for the formation of its pre-landing elliptical orbit.

At about 14:57 Moscow time, communication with the Luna-25 spacecraft was interrupted.

The measures taken on August 19 and 20 to search for the device and get into contact with it did not produce any results.

According to the results of a preliminary analysis, due to the deviation of the actual parameters of the impulse from the calculated ones, the device switched to an off-design orbit and ceased to exist as a result of a collision with the lunar surface.

A specially formed interdepartmental commission will deal with the issues of clarifying the reasons for the loss of the Moon.

Unconfirmed back-channel information (check Anatoly Zak’s RussianSpaceWeb Luna-Glob mission page for updates) indicated “computational error led to the final engine firing to be 1.5 times longer than required and thus resulting in deorbiting and crash of the spacecraft on the Moon”.


Soviet cosmonaut Alexei Leonov’s notes about mankind’s first-ever spacewalk on March 18, 1965 aboard Voskhod-2 - provide some interesting insights about the interplay of cosmonauts, engineers and politicians via X, have not verified

"Russian cosmonautics – it’s a comedy of horrors. A cosmonaut, who for the first time in the history of mankind ventured into outer space, was unable to get back on board. He was floating on the end of a 5-meter cable above the planet, but when it was time to get back in - it turned out that the spacesuit swelled and did not fit through the airlock. In order to get in, he had to depressurize the spacesuit to 0.27 of Earth’s pressure - such pressure corresponds to about 3 kilometers above Everest.

Miraculously, he didn’t lose consciousness. But then he couldn’t fit through the second airlock. He managed to get into it only by flagrantly violating the instructions - head first, not feet first. He then collapsed next to his comrade.

After barely catching breath, the news came - the automated navigation system for returning back to Earth was broken. Again, for the first time in the history of mankind, the spaceship had to return to the planet manually.

The one window on the new Voskhod-2 spaceship looked out to the side. Only the stars could be seen through this window. If you started the engine facing the wrong way, instead of returning, you would fly far away and stay there forever. The cosmonauts desperately crawled around the cabin, looked through the ill-fated porthole from different angles, made out from memory where the Big Dipper was and where the Earth should be, and finally started the engine.

It probably sounds funny now, but again, for the first time in the history of mankind, they took their seats with the rocket engine running, the acceleration of which was about to turn them into pancakes. Where the spacecraft will take them remained a mystery. They don’t remember much of the descent. They woke up, got out. There were snowdrifts up to their waists. It was cold: -30°C (-22°F).

The spaceship had a lot of survival equipment - fishing hooks, shark repellent, a single TT pistol, and so on. But they didn’t think about the cold. The cosmonauts took off their spacesuits, each poured out 5 liters of sweat, built a fire while naked, wrapped themselves thoroughly and waited, periodically clicking the morse code - ‘S.O.S.’

They didn’t vary the message - what else was there to signal to the whole planet? We are Soviet cosmonauts, we are in the middle of nowhere, we are not well… The signal was being blocked by trees. The cosmonauts guessed, moved through the snowdrifts.

Eventually, the SOS signal was picked up in Bonn. The Germans immediately informed the Kremlin.
Our people refused to believe the Germans. And at that time - the only thing the Mission Control Center knew about the missing cosmonauts was that they had landed somewhere in Russia.
Hundreds of helicopters were in the air combing the area. At the same time, TV reported that the cosmonauts had landed safely and were resting in a sanatorium.

The pause between this message and the appearance of the cosmonauts themselves on the screen was clearly dragging on. Brezhnev couldn’t stand it any longer, so he called Korolev and asked what the hell was going on. Korolev angrily replied: ‘My business is to launch cosmonauts, yours – to announce. You should hurry up, not me.’

Finally, one of the helicopters detected a campfire and two unfortunate cosmonauts near it. But it was impossible to land there. A group of skiers went on foot to clear the path to the site with axes. And gifts rained from the sky - warm clothes and cases of cognac. All the clothes got stuck on the trees, and the cognac cases were shattering all around, the astronauts swore grimly as they dodged them.’


The experience of Voskhod 2’s far off-course landing in the Russian north, where the cosmonauts retreated to their landing capsule due to the risk of wolves and brown bears they feared would only be annoyed if shot by the Makarov 9 mm pistol in their survival kit led to the development of the TP-82 cosmonaut survival pistol, a three-barrelled design, two of whose barrels fired 12.5×70 mm shotgun shells and one the 5.45×39 mm round used by the AK-74 rifle.


This was standard equipment on Soyuz spacecraft until 2006, when it was replaced by a semi-automatic pistol. Thus, as I noted in my 1998 article, “Blazing Satellites: Guns in Space”:

Now recall that the International Space Station will use docked Soyuz spacecraft as the crew’s lifeboat. Imagine trying to persuade folks back in 1986, when Ronald Reagan first proposed “Space Station Freedom”, that when it was finally completed in the next millennium its crew complement would include Russians—with guns .


Russia’s Luna-25 moon lander crashed into the lunar surface on Sunday after it lost control and spun out of orbit. The spacecraft was the first of a series of missions that Russia planned to send to the moon in the coming years.

The Luna-25 was launched on July 22 from the Vostochny Cosmodrome in Russia’s far east. It entered lunar orbit on August 12 and was scheduled to land on the south pole of the moon on August 21.

However, on August 19, the spacecraft reported an “abnormal situation” and lost contact with ground control. Roscosmos, the Russian space agency, said that the Luna-25 had “ceased to exist” as a result of the collision.

“During the operation, an emergency situation occurred on board the automatic station, which did not allow the maneuver to be performed with the specified parameters,” Roscosmos shared in a Telegram post on Saturday.

The Luna-25 was part of a program of renewed Russian interest in the moon. Russia plans to send a series of missions to the moon in the coming years, including a robotic rover and a manned mission.

(Update: I moved this item from its own topic to the existing Luna 25 topic. @Fourmilab — 2023-08-20 19:03 UTC)



In an ironic turn of events, there is an urban dictionary entry for the term.

And in an even weirder turn of events, the Pet Shop Boys – yes, the 80s band – recorded an eponymous song on their Lost album issued in 2023 (source)

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MOSCOW, August 21. /TASS/. Researchers from the Russian Academy of Sciences’ Keldysh Institute of Applied Mathematics have simulated the trajectory of the Luna-25 mission, figuring out where and when it crashed into the moon’s surface, the institute said in a statement on Telegram.

“The mathematical modeling of the trajectory of the Luna-25 spacecraft, carried out by experts from the Ballistic Center of the Russian Academy of Sciences’ Keldysh Institute of Applied Mathematics, made it possible to determine the time and place of its collision with the moon,” the statement reads.

According to the institute, the spacecraft fell into the 42-kilometer Pontecoulant G crater in the southern hemisphere of the moon at 2:58 p.m. Moscow time on August 19.


Here is more on 91 km diameter Pontécoulant crater on the Moon, at 58.7° S 66.0° E. The predicted time of impact was 2023-08-19 at 11:58 UTC.


Before and after images of Luna 25 impact site

NASA’s Lunar Reconnaissance Orbiter has imaged the crater made by the Luna 25 impact on the Moon in the above before (2020-06-27) and after (2023-08-24) photos. The Sun angle is different, resulting in the change in shadows on surface features. For details, see the 2023-08-31 article, “NASA’s LRO Observes Crater Likely from Luna 25 Impact”.

Roscosmos, Russia’s space agency, published an estimate of the impact point on Aug. 21. The LROC (short for LRO Camera) team and the LRO Mission Operations team were able to design and send commands to the LRO spacecraft on Aug. 22 to capture images of the site. The sequence began on Aug. 24 at 2:15 p.m. EDT (18:15 UTC) and was completed about four hours later, at 6:12 p.m. EDT (22:12 UTC). The LROC team compared images taken prior to the impact time and the sequence taken after and found a small new crater.

The new crater is about 10 meters in diameter and is located at 57.865 degrees south latitude and 61.360 degrees east longitude at an elevation of about minus 360 meters. The impact point was on the steep (greater than 20-degree grade) inner rim of Pontécoulant G crater, about 400 kilometers short of Luna 25’s intended landing point at 69.545 degrees south, 43.544 degrees east.


Roscosmos has issued a statement on the cause of Luna 25’s crash into the Moon on 2023-08-19 in a post on Telegram (in Russian). Here is a Google Translate rendering into English.

“Luna-25”: preliminary results of work to determine the reasons for the abnormal functioning of the station

On August 19, when issuing a correction pulse to transfer the spacecraft from a circular lunar orbit to an elliptical pre-landing orbit, the Luna-25 propulsion system operated for 127 seconds instead of the planned 84 seconds. As a result, the station switched to an undesigned open orbit and collided with the lunar surface.

It was established that the most likely cause of the accident was the abnormal functioning of the on-board control complex, associated with the failure to turn on the accelerometer unit in the BIUS-L device (angular velocity measurement unit) due to the possible entry into one data array of commands with different priorities for their execution by the device. In this case, the distribution of commands in data arrays is random (probabilistic) in nature.

In this regard, the on-board control complex received zero signals from the accelerometers of the BIUS-L device. This did not allow, when issuing a corrective pulse, to record the moment the required speed was reached and to timely turn off the spacecraft propulsion system, as a result of which its shutdown occurred according to a temporary setting.

Recommendations for additional activities for subsequent lunar missions have been formed.

Apparently, due to the command to turn on the accelerometer’s having too low a priority on the spacecraft’s internal network, it was never switched on and thus never sent the signal to the engine to shut down when the commanded delta-v had been achieved. The engine continued to burn for 127 seconds instead of the intended 84, lowering the periapsis on the other side of the orbit below the lunar surface, resulting in unintended lithobraking when the orbiter arrived there.


The report reads like insufficient testing was part of the problem leading to the rapid terminal disassembly event. St Chat offered a slightly easier to read translation of the last two paragraphs. What’s not clear to me is how to interpret the statement about the “distribution of commands in the data arrays has a random (probabilistic) nature”?

Does it mean that turning on the accelerometer was pre-empted by too many other higher priority commands (priority starvation) or some other random/probabilistic event occured preempting the accelerometer turning on, perhaps related to actual space conditions vs test in a lab.

It was determined that the most likely cause of the accident was the abnormal functioning of the onboard control complex, related to the failure of the accelerometer block in the BIUS-L instrument (angular velocity measurement unit) due to the possible inclusion of commands with different priorities in a single data array and their execution by the instrument. The distribution of commands in the data arrays has a random (probabilistic) nature.

As a result, zero signals from the accelerometers of the BIUS-L instrument were received in the onboard control complex. This prevented the timely detection of the required velocity gain and the timely shutdown of the propulsion system of the spacecraft, resulting in its shutdown occurring based on a time setpoint.


Hah! Oh, that’s good. Who gets credit for that one?


Dunno. I first heard it from Scott Manley, but he may have been quoting a term from Kerbal Space Program player lore.