SpaceX’s Falcon 9 rocket is on a crash course into Moon this week. Here’s why

The rocket was carrying two rovers: Blue Ghost and Resilience. Blue Ghost landed successfully and carried on with its historic mission, and Resilience crashed while trying to touch down.

As per a recent study about the upcoming impact of the rocket published on the arXiv digital repository, the 4,000-kg rocket body “was abandoned in a moon-crossing high-Earth orbit”.

Julianna Scheiman, director of Nasa satellite missions at SpaceX, stated on Monday at a press conference about the company’s Crew-13 astronaut launch to the International Space Station, which is scheduled for September 12, that SpaceX carried out “a different manoeuvre [than deorbiting] to ensure that the second stage itself is safe per the appropriate rules and regulations”.

The safety manoeuvre did not actually move the rocket to a safer location, yet the natural force acted on the rocket and changed its path, leading the trajectory to a crash.

Scheiman said, “What has happened is, essentially, a mixture of solar activity and gravity forces has put it on a path towards the Moon.”

Why are scientists intrigued to see the rocket crash?

Astronomers and lunar scientists are awaiting the upcoming lunar impact, even though it is expected to occur on the Moon’s sunlit side, making it difficult for most observers on Earth to witness. However, researchers say powerful telescopes may still be able to detect the plume of debris, or ejecta, thrown up by the collision. The event is expected to provide valuable scientific data, helping researchers refine techniques for measuring impact flashes, locating impact sites using seismic data, and improving understanding of the risks that space debris poses to future lunar missions.

“The event provides an opportunity to test pipelines for measuring flash properties to locate impact events seismically and to better understand the multimodal hazards posed to future lunar infrastructure and astronauts from space debris impacting the moon,” Fernando and his colleagues wrote in their study.

Those risks could soon become a practical concern rather than a theoretical one. Nasa plans to establish a sustained human presence near the Moon’s south pole through its Artemis programme over the next decade.

SpaceX says it is working with Nasa and other agencies to develop safer disposal methods for spent rocket stages.

“It’s one of the things that we’re working in partnership with Nasa and the other appropriate agencies,” said Scheiman. “What is the best future disposal path for high-energy missions that are in the sun-Earth-moon system?”

The Falcon 9 upper stage will not be the first rocket body to strike the Moon. Several Saturn V third stages from Nasa’s Apollo missions were deliberately crashed into the lunar surface for scientific research. On March 4, 2022, a mystery rocket stage slammed into the Moon, creating an unusual double crater. Scientists later identified the impactor as the upper stage of China’s Long March 3C rocket, which launched the uncrewed Chang’e 5-T1 lunar mission in October 2014.