A four-tonne piece of a discarded SpaceX rocket that has been floating in space since last year is believed to have unintentionally crashed into the moon at high speed, in a collision that poses no danger to Earth but was expected to blast out a new lunar crater.
The object, the size of a building, is part of the SpaceX Falcon 9 rocket that had launched a lunar lander from the US company Firefly Aerospace toward the moon in January 2025.
The rocket body was due to hit the moon about 6.35am Irish time, crashing into its surface at 8,690km/h. The impact was predicted to kick up a miles-long plume of lunar dust that, while illuminated by sunlight, would be difficult to spot with the naked eye from Earth.
Professional and amateur astronomers using high-quality telescopes and cameras were not able to immediately confirm the impact on Wednesday, possibly due to the impact site being close to the visible edges of the moon.
Nasa has said the impact was expected to create a crater about 18 metres wide and four metres deep and throw dust and rock outward as ejecta.
The space agency said it would look for opportunities to image the site before and after the impact, with any data collected helping scientists “better understand artificial impacts and their exploration implications”.
Nasa’s spokesperson Jimi Russell said on Tuesday: “The impact poses no danger to Earth and Nasa scientists are planning to collect lunar data from the event and refine techniques for tracking objects in space.”
Such rocket parts, known as stages, typically fall back into Earth’s atmosphere and burn up or plunge into the ocean after boosting the rocket’s payload to a precise spot in orbit.
But because the January 2025 lunar lander mission required more thrust than missions closer to Earth, the rocket’s second stage remained in space, floating aimlessly among thousands of other pieces of space junk that active satellites must steer clear of.
It was not until this year that astronomers determined that the rocket stage, which had dumped its remaining fuel and cannot be controlled, was on an orbital trajectory ending at the moon.
Julianna Scheiman, SpaceX’s director of Nasa science and Dragon programmes, told reporters on Monday: “What has happened is essentially a mixture of solar activity and gravity forces have put it on a path toward the moon.”
Bill Gray, the creator of a widely used astronomy software who published a report on the stage’s impact in April, said: “This may be of some – probably minor – scientific interest, and we may learn some things from it.
“It doesn’t present any danger to anyone, though it does highlight a certain carelessness about how leftover space hardware [space junk] is disposed of.”
Space junk impacts on the moon are rare. A Chinese rocket stage crashed into the moon in March 2022 after completing a lunar test mission. In 2009, Nasa intentionally crashed a rocket stage into the moon to study the plume of lunar material kicked up by the impact.
Several spacecraft intending to softly land on the moon in recent years have crashed instead, including Russia’s nuclear-powered Luna-25 mission in 2023 and India’s Chandrayaan-2 lander mission in 2019.
Israel’s Beresheet lander also crashed in 2019. Among the Israeli lander’s payloads were tiny tardigrades, microscopic animals known for surviving radiation and other harsh environments and which may still be on the surface.
Scheiman said Nasa and SpaceX were discussing ways to prevent future lunar impacts.
On Tuesday SpaceX reported a smaller loss than Wall Street expected along with a surge in revenue in its first quarterly report as a public company. Despite this, shares tumbled as investors remained sceptical about the company’s ability to deliver on its lofty promises. – Guardian/Reuters
