On August 20th, local time, the Russian state space corporation Roscosmos announced that, according to preliminary analysis, the lunar exploration spacecraft Luna-25 had deviated from its planned orbit and collided with the lunar surface. It no longer exists.
On August 11th, the Soyuz rocket carrying Luna-25 was launched from Russia’s Vostok Cosmodrome.
Luna-25 was Russia’s first lunar probe since the 1970s. It was launched by a rocket on the 11th of this month, entered lunar orbit on the 16th, and was originally scheduled to make a gentle landing on the Moon’s south pole on the 21st. Its primary mission, if successful, would have been a historic first for humanity.
Whether it’s government space programs or the lunar exploration ambitions of private companies, there’s a strong desire to reach the Moon’s south pole, as it’s believed to contain water ice that astronauts could use in the future.
Failure Stems from Poor Preparation and Human Error
The two riskiest and most tense moments of any moon mission are launch and landing. In the past four years, three lunar landing attempts by India’s space agency, the non-profit Israeli space organization SpaceIL, and Japan’s iSpace have all ended in failure during the final minutes of the landing phase.
Luna-25 couldn’t enter its intended orbit, and the direct cause was an abnormal engine ignition. Engine issues often stem from subpar manufacturing processes and incomplete testing procedures, which ultimately led to the mission’s failure.
Apart from the technical issues, human factors can also lead to significant mistakes, as was the case with NASA’s Mars Climate Orbiter in 1999:
The spacecraft’s flight system software used pounds for force calculations, while ground-based personnel entered adjustments and thrust commands using Newtons. This error caused the probe to enter Mars’ atmosphere at an incorrect altitude and ultimately burn up.
A view of the Zeeman volcano on the far side of the Moon captured by Luna-25.
Natan Eismont, a senior scientist at the Russian Academy of Sciences’ Space Research Institute and the director of Luna-25’s operations, said, “During the firing to adjust the probe’s course, the engine didn’t work as planned. Observers on the ground also noticed that the command parameters were different from the calculated values.”
“In reality, up to the last firing, the team’s various reactions were quite successful. Unfortunately, the final high-thrust firing was designed to bring Luna-25 into orbit before landing (within about 18 km), but it didn’t go as planned. It’s likely that the braking force was too strong or misaligned.”
Eismont advised that future lunar missions should dedicate more time to practical work.
The technical team directly involved in the mission had to make a decision: proceed with the landing attempt or remain in a circular orbit to address the issue further. They made their decision, and the management board will have to determine whether the assessment was correct.
It’s worth noting that Russian media reports on the Luna-25 mission have been relatively low-key, and their attitude towards the accident has been rather calm.
The broadcast on Russia’s first channel took only 40 seconds to report the early conclusion of the Luna-25 mission, with a positive comment: “Scientists have obtained valuable information about the moon’s surface.”
Equipment Not Built to Withstand Cold and Radiation
In recent decades, Russia’s space exploration activities have fallen far behind the Soviet era. The most recent fully successful exploration was nearly 35 years ago during the Soviet era.
In December 1984, Vega 1 and Vega 2 were launched six days apart. Six months later, the two spacecraft reached Venus and each released a lander that ultimately floated in Venus’ atmosphere. In March 1986, Vega 1 and 2 approached within about 8,000 km of Halley’s Comet using Venus’ gravitational assistance and sent back a large amount of images and data about Halley’s Comet and the dust and gas surrounding its nucleus.
Mars missions deployed by the Soviet Union in 1988 and by Russia in 1996 both ended in failure.
The Phobos-Soil mission in 2011 mentioned above was a major failure. The spacecraft was supposed to land on the larger of Mars’ two moons, Phobos, and return soil and rock samples to Earth, but it never left Earth’s orbit. Months later, Phobos-Soil burned up in Earth’s atmosphere.
Subsequent investigations revealed that Russia’s space agency was facing financial difficulties at the time and didn’t want to spend more on manufacturing and testing, using electronic equipment that hadn’t been proven to withstand space’s harsh environment.
Pressure Is Now on India
Luna-25 was originally intended to complete its mission in a year to study the Moon’s surface composition, verify the feasibility of technologies to be used in a series of lunar missions (Luna-26, 27, 28), and establish a foundation for Russia’s future lunar base, possibly in collaboration with China.
Russia’s lunar mission schedule has been delayed by several years, and with the Luna-25 mishap, further delays may be unavoidable. Roscosmos now faces a difficult choice:
Retry the Luna-25 mission or pause the soft landing technology testing to proceed with a more ambitious follow-up mission?
While NASA and the European Space Agency maintain cooperation with Russia on the International Space Station, all other joint space programs have been suspended since the outbreak of the Russia-Ukraine conflict. Regarding lunar landing missions, Russia has now lost critical components provided by Europe and will need to become more self-reliant. They have been working on developing next-generation space hardware, especially electronics capable of withstanding space’s harsh conditions.
Anatoly Zak, a longtime observer of Russia’s space activities, noted, “Without high-quality electronic equipment, you really can’t function in space for an extended period. Russia’s space program has, in reality, suffered due to equipment issues.”
On the other hand, India has an opportunity to land its first lunar probe near the Moon’s south pole. Its Chandrayaan-3 mission, launched in July, took a more looping but fuel-efficient trajectory to reach the Moon. According to the plan, Chandrayaan-3 will attempt a soft landing near the lunar south pole on the 23rd of this month.