A lunar lander likely plummeted 3 miles before smashing into the lunar surface after a historic attempt to make a soft touchdown on the moon, the Japanese company Ispace revealed Friday.
The misstep can probably be traced to a software issue and an incorrect measurement of the spacecraft’s altitude as it attempted to find its footing on the moon, the company said.
“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 (1.9 miles) in elevation on the lunar surface, which was determined to be the rim of a crater,” according to a Friday news release from Ispace, which built the spacecraft.
The Hakuto-R lunar lander was aiming to make history in late April in its attempt to become the first spacecraft — developed by a private company rather than a government space agency — to make a controlled landing on the moon. The lander also carried a rover developed in the United Arab Emirates.
But shortly after Hakuto-R’s expected landing time, flight controllers on the ground revealed they were not immediately able to regain contact, prompting the company to presume the spacecraft was lost.
The spacecraft’s fate was confirmed this week when NASA announced that its Lunar Reconnaissance Orbiter captured 10 images of Hakuto-R’s landing site and found what appears to be at least four pieces of debris from the crash landing.
“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 (3.1 miles) above the lunar surface,” according to Ispace’s news release. “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.”
Landing attempt
The lander launched atop a SpaceX rocket from Cape Canaveral, Florida, on December 11. The spacecraft made a three-month trek to the moon, which lies about 239,000 miles (384,600 kilometers) from Earth. Hakuto-R then entered orbit around its target, using a low-energy trajectory. Overall, the journey took the lander about 870,000 miles (1.4 million kilometers) through space.
During a news conference Friday, Ispace CEO Takeshi Hakamada reiterated that the Hakuto-R spacecraft was able to transmit data right up until its failed landing attempt. The company received valuable data to fine-tune its lunar lander design for another attempt, Hakamada said.
The lunar lander was carrying the Rashid rover — the first Arab-built lunar spacecraft, which was developed by Mohammed bin Rashid Space Centre in Dubai, United Arab Emirates.
Only three countries have executed a controlled landing on the moon — the United States, the former Soviet Union and China. The US remains the only country to have put humans on the moon.
Japan’s Ispace had a different approach from earlier lunar missions, attempting to land its spacecraft on the moon as a for-profit business rather than under the banner of a single country.
Even before the failed landing attempt, Ispace had been bracing for mishaps. “Recognizing the possibility of an anomaly during the mission, the results will be weighed and evaluated against the criteria and incorporated into future missions already in development between now and 2025,” the company noted in a December 11 post.
Had the landing been successful, the 22-pound (10-kilogram) Rashid rover would have been expected to emerge from the Hakuto-R. Rashid would have spent “most of the 14-day lunar daytime exploring the Atlas Crater on the northeast of the Moon,” according to the European Space Agency, which helped design the rover’s wheels.
Ispace’s backstory
Japan’s Ispace is one of several companies that competed in the Google Lunar XPrize, which offered a $20 million reward to the firm that could put a robotic rover on the moon, travel a couple of thousand feet and transmit data back to Earth.
The Google-sponsored space race was scrapped in 2018 when no competitor was able to meet the deadline, but Ispace was among the companies that chose to continue pursuing the mission.
Israel-based company SpaceIL was the first XPrize contestant to attempt to put its lander on the moon after the program ended. The Israeli Beresheet spacecraft crashed in 2019 after ground teams lost contact with the lander as it approached the surface.
That same year, the Indian Space and Research Organisation lost contact with a lunar lander shortly before it was slated to touch down on the moon. Communication with the spacecraft was never regained, and images from NASA’s Lunar Reconnaissance Orbiter later revealed the crash site and final resting place of the mission.
A mission to retrieve lunar soil samples on behalf of NASA’s Artemis program, which intends to use commercial lunar landers to explore the moon’s surface, is part of Ispace’s future plans.