On June 5th, ispace’s M2 lunar lander attempted to touchdown on the surface of the Moon. Unfortunately, the landing was unsuccessful, with the lander expected to have impacted the surface, being destroyed in the process.
During the official stream, we were shown live telemetry which gives us a hint into what happened to the vehicle and during which phase of its landing.
Landing Attempt
The live stream began, and not long after, the lander, named Resilience, started preparing for touchdown. Specifically, there are 6 main phases that occur within the final hour before a scheduled touchdown. The first that took place was the de-orbit insertion burn. It’s worth noting that during the first two phases, we weren’t provided live data. For that initial phase, it was a quick burn using all the lander’s engines with the purpose of decelerating and lowering its altitude. It only took around a minute and occurred when the lander was around 100km high, traveling close to 5800km/h.
The next phase was the coast descending phase. Here, the lander wasn’t firing any engines and instead remained inactive as its altitude decreased to around 20km. This phase lasted around 50 minutes, leading up to the final pre-landing activities.
From this point on, we began getting live data as the lander got closer to its scheduled landing. The next phase was the breaking burn phase. All engines fired with the goal of reducing as much horizontal velocity as possible. This mission milestone lasted around 10 minutes.
Toward the start of this phase, there wasn’t any data for the speed but its altitude was over 18000m. They cut away from the data and returned around 7 minutes later. At this point, we could see a speed of around 1800 km/h, and an altitude under 12,000m.
Skipping ahead a few minutes, the lander made it to its fourth phase, the pitch-up phase. Again, looking at the data, everything seemed to be going well at this point. For reference, at this point in the mission, based on estimates from the company beforehand, they noted that the lander should have lowered both its altitude to around 3000m and its speed to be in the 300s. When the pitch-up phase begins, telemetry shows just about exactly that, suggesting everything is going as planned with only a few minutes left before touchdown.
However, this is where things begin to take a turn. The fourth phase is a breaking burn and pitch-up phase. The goal here is to reduce velocity from around 380km/h to 120 and lower the altitude to just 1 km. Looking at the livestream, all engines are firing, and both the speed and altitude continue to reduce. That being said, the altitude is reducing much faster than it should be in theory. This phase of descent is only meant to last around 1 minute in total, meaning with it beginning at around 2 and a half minutes left before touchdown, it should have come to an end with 1:30 left.
In reality, only 30 seconds after the start of this phase, the data shows it already passing below 1km in altitude, something not supposed to happen for another 30 seconds or so. We can see all engines firing but seconds later while still at a speed of above 200 km/h, that altitude goes to 0, with the final number showing no speed and -223 m in altitude. Right as that happened, you could see the engines cut off and mission control call out “final approach started”. However, from that point on, no more data was provided, and instead, we just got views of nervous-looking faces within mission control.
Not only that, but during that sequence, if we are to believe the engine graphics, it shows all the engines firing but then stopping with the exception of the main engine, at a time when the vehicle would need to be slowing down more than ever. Either way, not long after, they ended the livestream without an official status update on the lander’s condition.
It’s important to point out that all of the livestream data should be taken with a grain of salt, as missions like these can usually show some inaccurate data. Even still, it does help paint a picture of what happened. With everything shown, at this point, it was believed that the lander ended up impacting the Moon much faster than planned, likely destroying itself on impact.
An hour or so after the live stream ended, the company tweeted saying, “At this moment, we have not yet been able to establish communication with RESILIENCE, but ispace engineers in our Mission Control Center are continuing to work to contact the lander.”
A few hours later, they released a statement and held a press conference. In the statement they say, “As of 8:00 a.m. on June 6, 2025, mission controllers have determined that it is unlikely that communication with the lander will be restored and therefore completing Success 9, is not achievable. It has been decided to conclude the mission.”
They go on to say, “Based on the currently available data, the Mission Control Center has been able to confirm the following: The laser rangefinder used to measure the distance to the lunar surface experienced delays in obtaining valid measurement values. As a result, the lander was unable to decelerate sufficiently to reach the required speed for the planned lunar landing. Based on these circumstances, it is currently assumed that the lander likely performed a hard landing on the lunar surface. After communication with the lander was lost, a command was sent to reboot the lander, but communication was unable to be re-established” they said.
During the press conference they were quoted saying, “There is a sensor to measure the altitude and there was a moment where the data was too slow. So actually it was descending lower than we thought. Also it was not slowing down enough, these are the facts. They are similar to mission 1, but there are different phenomena that we are observing, so we have to look at the root cause in more detail. So I cannot say at this point that it was because of the same factor. The issues seem to be different from mission one” he said.
For context, this actually is the second time ispace has attempted to land on the Moon. The first attempt was a few years ago in early 2023. On M1, the lander began the descent sequence from an altitude of approximately 100 kms above the lunar surface. At the end of the planned landing sequence, it approached the lunar surface at a speed of less than 1 m/s. The operation was confirmed to have been in accordance with expectations until about 1:43 a.m., which was the scheduled landing time.
During the period of descent, an unexpected behavior occurred with the lander’s altitude measurement. While the lander estimated its own altitude to be zero, or on the lunar surface, it was later determined to be at an altitude of approximately 5 kms above the lunar surface. After reaching the scheduled landing time, the lander continued to descend at a low speed until the propulsion system ran out of fuel. At that time, the controlled descent of the lander ceased, and it is believed to have free-fallen to the Moon’s surface.
They determined that the most likely reason for the lander’s incorrect altitude estimation was that the software did not perform as expected. Based on the review of the flight data, it was observed that, as the lander was navigating to the planned landing site, the altitude measured by the onboard sensors rose sharply when it passed over a large cliff approximately 3 kms in elevation on the lunar surface, which was determined to be the rim of a crater.
According to the analysis of the flight data, a larger-than-expected discrepancy occurred between the measured altitude value and the estimated altitude value set in advance. The onboard software determined in error that the cause of this discrepancy was an abnormal value reported by the sensor, and thereafter the altitude data measured by the sensor was intercepted. This filter function, designed to reject an altitude measurement having a large gap from the lander’s estimation, was included as a robust measure to maintain stable operation of the lander in the event of a hardware issue including an incorrect altitude measurement by the sensor.
One major contributing factor to this design issue was a decision to modify the landing site after critical design review completed in February 2021. This modification influenced the verification and validation plan despite numerous landing simulations carried out before the landing. It’ll be interesting to see over the next few weeks as ispace investigates the recent loss as to exactly what the cause was, and if it shared any similarity to the previous mission.
This lander adds to a growing list of lunar landers struggling to successfully land on the Moon, highlighting how difficult it is. Even still, the company has more lunar landings planned in the future.
Conclusion
Earlier today, ispace attempted to touch down on the Moon. Unfortunately, with only around 1 minute left until the expected landing time, telemetry was lost. It was later confirmed by the company that the lander had likely impacted the surface and was destroyed, marking the end of the M2 mission.