The Japanese company iSpace has published the results of the investigation into the accident of the apparatus “Hakuto-R”, which crashed during the moon landing. The cause of the failure was a bug in the probe’s software.

“Hakuto-R” was made by a team of engineers who once participated in the Google Lunar X PRIZE competition. The Japanese apparatus went into space on December 11, 2022. Together with him, the first Arab navigator “Rashid” flew to the moon. The 10-kilogram device was made by the Mohammed Bin Rashid Space Center (UAE).

In March 2023, “Hakuto-R” entered a permanent orbit around the moon, after which experts began to prepare it for landing. It took place on April 25 and initially took place in normal mode. However, just minutes before contact with the surface, communication with the device was lost. Later, the American probe LRO photographed the debris left after the Hakuto-R crash.

Cause of “Hakuto-R” crash

On May 26, iSpace released a report on the results of the Hakuto-R crash investigation. Engineers concluded that this was due to a software glitch. During the descent, the Japanese aircraft flew at high speed, which was part of the shaft of a large impact crater. The discrepancy between the measured altitude value and the calculated value turned out to be larger than planned, because the probe’s on-board computer mistakenly decided that the instrument’s altimeter was giving incorrect data, and then began to “filter” them.

This resulted in the system deciding that the Hakuto-R had already landed when it was 5km above the lunar surface. After that, the vehicle’s engines continued to operate in low-thrust mode until it ran out of fuel and crashed onto the Moon.

iSpace also cites that one of the indirect causes of the crash was a rather late decision to change the mission’s landing site. After that, iSpace experts performed a series of additional landing simulations, but did not take into account the changing terrain. As a result, a fatal error was made in the software.

According to the company’s statement, it will take into account the lessons learned from the Hakuto-R landing and make appropriate changes to the software and landing procedures of future Moon missions. Their implementation is planned for 2024-2025.