​Post-Soviet Russia has sent three interplanetary (beyond Earth orbit) probes in the past three decades, and all three failed: Mars-96 in 1996, Phobos-Grunt in 2011, and Luna-25 a few days ago. Luna-25 is the latest such failure: the probe, which was supposed to restart the lunar space exploration program, crashed on the lunar surface after a failed orbital maneuver before selenization was attempted.

First of all, I must say that Luna-25 has nothing to do with the former Lunar Exploration Program, which ended with the Luna-24 mission in 1976. The mission name was probably chosen to emphasize some continuity, but the engineers who worked in 1976 have either retired or are no longer with us, and Luna 25 used completely different technologies, from new engines to new onboard software (maybe too new, I’ll come back to that). So in the case of Luna-25, we cannot refer to the Soviet experience of lunar exploration, since the mission was to be the first in a series of increasingly ambitious lunar missions, with which today’s Russia would confirm its prestige.

After an eight-day flight and two successful orbit corrections, on Saturday, August 19, the Luna-25 probe was in lunar orbit, an orbit with an apogee of 113 km (that is, the highest point of the orbit) and a periapsis of 90 km. (that is, the lowest point of the orbit and closest to the surface of the Moon). Parenthetically, orbits are rarely circles, they are mostly ellipses, which means that the distance from the surface is not constant, having a maximum (apoapsis) and a minimum (periapsis). To selenize, the probe had to get even closer to the moon’s surface, so on Saturday it positioned its main engines in the direction of travel in lunar orbit and activated the engines to brake to descend to periapsis about 18 km.

From here, the lander could arrive these days on the surface, somewhere near the south pole of the Moon, according to the plan. But something went wrong on board the probe: we don’t know if it was a problem with the flight software or just a malfunction of the engines, but they apparently worked 50% more than they were programmed to, which means that the probe slowed down more, than needed The periapsis of the orbit became negative, which means that the trajectory of the probe will cross the surface of the Moon, which happened several dozen minutes later, when Luna-25 crashed into the Moon at a speed of more than 1.5 km/s.

Roscosmos reported the loss of contact with the probe in the afternoon of August 19. The Russian space agency does not usually report failures unless they are catastrophic and obvious. If there was still hope that the probe would be intact and communication with it would be restored, Roscosmos would not have made such an announcement. Since then, it has become clear that the probe has serious problems. A few hours later, Roscosmos confirmed that the probe crashed on the moon after a failed attempt to change its orbit.

As I said above, “Luna-25” was a new mission, so the failure is not surprising. Add to this the corruption in the Russian government system and the sanctions that have affected the Russian space program, and we can easily imagine the conditions that led to this failure. Typically, engineers learn from such mistakes and implement the lessons learned into new, more reliable missions. So did India, which, after the failure of Chandrayaan-2 in 2019, built the Chandrayaan-3 probe, which is now being prepared for selenization. This is being done by Israel, which, after the failure of the Beresheet probe (also from 2019), is preparing to launch the Beresheet-2 probe in 2025. What will happen in Russia after the failure of Luna-25? Given the special situation there, it is too early to say anything.

Formally, Luna-25 was part of the International Lunar Research Station (ILRS) lunar program initiated by China and Russia in 2021, which was later joined by Venezuela, Pakistan and the United Arab Emirates, through which these countries began a joint lunar exploration program , a copy of the Artemis Accords coordinated by the United States. This is even if the Luna-25 mission was discussed before 2000, later it was considered part of the ILRS. It remains to be seen what Russia’s role in ILRS will be under these conditions and whether China will become the de facto leader of this program (Chinese probes not only recently landed, but also brought soil samples from the moon).

Roscosmos planned to launch the Luna-26 probe in 2027. Since this launch does not include a lander, the mission complexity level is, at least theoretically, lower, so it would not be difficult to imagine that this launch could take place in 2027-2028, if the issues leading up to that time are resolved by the Luna 25 accident . The next lunar probe, Luna-27, was supposed to be launched in 2028 and land on the South Pole of the Moon, followed by Luna-28 no earlier than 2030, which aims to deliver lunar soil samples from the South Pole.

Of course, those missions will be delayed, now even more so, and it will be many years before Russia attempts another satellite landing of its own probe. As for manned missions to the moon, I don’t think we can seriously discuss them, maybe sometime after 2035-2040.

Meanwhile, we await the landing of India’s Chadrayaan-3 mission (scheduled for Wednesday, August 23) and look forward to the launch of Japan’s Smart Lander for the Exploration of the Moon (SLIM), scheduled for Saturday, August 26 aboard Japan’s H-IIB.

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