Private Athena lunar lander toppled over on the moon and was declared dead the next day

A Houston-based company, Intuitive Machines, designed the second robotic probe for lunar exploration, Athena, which ended up on its side shortly after touching down on the moon's south pole on March 6. Months after its unsuccessful landing attempt, the reason behind the toppling of the Athena lunar lander comes to light, as reported on Space.com

The lander's unfortunate orientation severely hampered its ability to collect solar energy through solar panels. Consequently, with its power source compromised, it was declared dead just a day later. Following a detailed autopsy analysis conducted over two months, Intuitive Machines has now identified three issues that collectively led to the lander's instability and eventual fall.

Firstly, the readings from Athena's laser altimeter — the device crucial for determining the lander's height from the lunar surface — was compromised by interference. According to Intuitive Machines' CEO, Steve Altemus, on May 13, "In the final phase of [Athena's] descent, we saw signal noise and distortion that did not allow for accurate altitude readings."

Furthermore, the challenging lighting conditions at Athena's landing site, located approximately 100 miles from the south pole of the moon, presented another obstacle. On this, Altemus shared, "South Pole topography and low-angle sunlight created long shadows and dim lighting conditions that challenged the precision capability of our landing system."

The third contributing factor to Athena's mishap was its reduced ability to recognize craters in the landing area. Its optical navigation system relied on images of the lunar surface captured by NASA's  Lunar Reconnaissance Orbiter (LRO) at an altitude of 62 miles. Citing this key piece of information, Altemus said, "This LRO imagery could not accurately account for how craters appear at lower altitudes with south pole lighting conditions as you approach the landing site."

Historically, only 5 countries have achieved soft landings on the lunar surface: the former Soviet Nation, the United States, China, India, and, most recently, Japan. Looking ahead, both the United States and China have ambitious plans to land astronauts on the moon within this decade. Both nations are also actively engaging allies and assigning significant roles to their private space companies in the development of the necessary spacecraft, as mentioned on Reuters.

On a mission to avoid a repeat of Athena's fate, Intuitive Missions is actively working on the lander's stability, slated for the IM-3 mission in 2026. According to Altemus, the company is trying to apply the lessons learned from IM-1 and IM-2 missions to implement crucial fixes. During Tuesday's call, Altemus shared, "We've added dissimilar and redundant altimeters to the sensor suite, and they're going through more rigorous and extreme flight-like testing than we've done before." To explain it even better, he added, "We've incorporated an additional lighting-independent sensor for surface velocity measurements. We've expanded the onboard terrain crater database for enhanced navigation across the surface of the moon." The team is also utilizing the detailed South Pole imagery from IM-2 to train machine-learning algorithms, with a goal of enhancing navigation and crater-tracking for future missions. Lastly, with optimism, Altemus shared, "Moving forward, we will succeed. Land softly, land upright, land ready to operate."