A discarded SpaceX rocket is heading toward the Moon. Space object tracking expert Bill Gray calculated that the Falcon 9 second stage will crash near the Einstein Crater on the western edge of the Moon’s near side in the early hours of the 5th, around 2:34 a.m. U.S. Eastern Time. The impact speed is about 8,700 km/h, roughly seven times the speed of sound.
The upper stage is about 12 meters long and weighs about 4,500 kilograms. It was launched in January last year carrying two commercial lunar landers, including Firefly Aerospace’s Blue Ghost. The first stage returned to Earth and was recovered, but the second stage, having completed its mission, was left in an elliptical orbit crossing the Moon’s path and has been drifting for more than a year.
The collision energy is estimated to be equivalent to 3 tons of TNT. Benjamin Fernando of Los Alamos National Laboratory said a new crater about 27 meters in diameter and 5 meters deep is likely to form.
The flash will disappear in less than a second, but a dust column rising several kilometers may remain visible through telescopes for tens of minutes. NASA’s Lunar Reconnaissance Orbiter (LRO) and South Korea’s lunar orbiter Danuri are also expected to collect data before and after the impact.
There have been only two cases of an artificial object unintentionally crashing onto the Moon, the previous one being debris from a Chinese rocket that fell on the far side in 2022.
This time, the impact will occur on the near side visible from Earth, making observation conditions much better. More importantly, the object’s identity is known. An impact from an artificial object whose mass, size, and velocity are all confirmed could serve as a benchmark for studies of natural meteorites. It is a rare opportunity to verify impact physics models with real-world measurements.
Structurally, this incident exposes a regulatory gap in deep-space orbit management. In low Earth orbit, there are rules requiring defunct satellites and rocket stages to be disposed of within a certain period.
The U.S. Federal Communications Commission requires low-Earth-orbit satellites to leave orbit within five years. The situation is different for trajectories traveling to and from the Moon. There is effectively no disposal obligation.
Falcon 9 has been launched more than 600 times, and unlike the recoverable first stage, the second stage is entirely disposable. As lunar missions increase, more abandoned upper stages accumulate.
The scientific community sees the collision as an opportunity rather than a threat. Fernando said, “The reason for interest is to understand how dangerous debris impacts could be for future astronauts.” Gray warned that “space is getting crowded,” highlighting the accumulation of debris itself.
Views also differ over responsibility. During the 2022 impact, astrophysicist Jonathan McDowell pointed out that the practice of leaving objects in deep space is not the fault of any specific company, but a problem rooted in industry standards. This time as well, some argue the impact could have been avoided by sending the stage into a solar orbit with remaining fuel, but there was no obligation to do so.
There are also voices cautioning against overstating the danger. The Moon is frequently struck by natural meteoroids traveling at 10 to 20 km per second. This impact is slower than that, and there are no facilities at immediate risk.
This collision signals that the space between Earth and the Moon is becoming a new congestion zone.
NASA is sequentially deploying commercial landers through its private lunar cargo program, and China, India, and Japan are also expanding independent lunar exploration. If each lander leaves one rocket upper stage on a Moon-crossing trajectory, incidents like this will become not a matter of possibility but of time.
The Moon’s environment makes the problem worse. With no atmosphere, debris does not burn up and disappear. Fragments thrown up by an impact can pose a direct threat to lunar-orbit assets and future surface facilities.
A 4.5-ton object falling at 8,700 km/h will not be a mere observation target once human bases are established; it will be a disaster factor. The imbalance in monitoring is also clear.
Objects in low Earth orbit are continuously tracked by the U.S. Space Force’s surveillance network and commercial tracking firms, but deep-space debris depends on calculations from individual researchers like Gray. In other words, gaps in monitoring and gaps in rules overlap.
There is also a race to set the standards first. As lunar resource development and base construction become more visible, who designs the traffic rules for Earth-Moon space first will be directly tied to leadership over the space order. The data and discussions left by this collision will become the first basis for those rules.
The most fundamental technical solution is not to abandon the second stage in the first place. SpaceX is developing Starship, a fully reusable launch vehicle intended to replace Falcon 9.
It has already succeeded in catching the Super Heavy booster with the launch tower and has conducted 12 test launches so far, with a design that aims to return even the second-stage spacecraft. If Starship is commercialized, vehicles that complete lunar missions will return to Earth instead of becoming debris.
A newer entrant is taking the approach one step further. The U.S. startup Stoke Space is developing Nova with second-stage reusability built into the design from the start. Its second stage features a regeneratively cooled metal heat shield and hydrogen engine, and is designed to return by vertical landing after completing its mission.
The company is working with NASA on reentry technology with first launch targeted for the end of this year, and it has even built in the capability to capture orbital debris and bring it back to Earth. Reusability began as an economic logic to reduce launch costs, but it is also the only disposal method that does not create debris in the first place.
Until the transition to reuse is complete, disposal maneuvers are the practical alternative. That means using remaining fuel after mission completion to push upper stages into solar orbit or to carry out controlled reentry.
It has been pointed out that this Falcon 9 upper stage could also have been sent into solar orbit to avoid the collision. The problem is not that the technology does not exist, but that there is no obligation to use it.
If each country’s launch licensing authority explicitly requires upper-stage disposal plans for deep-space missions and reflects a fuel reserve for disposal maneuvers in the design requirements, the situation could change.
This would be an extension of the FCC’s five-year disposal rule for low-Earth-orbit satellites into deep space. NASA could also immediately require upper-stage disposal provisions in its contracts for commercial lunar lander transport. Using contracts to create norms moves faster than legislation.
International norms could take a cue from Europe’s precedent. The “Zero Debris Charter” led by the European Space Agency in 2023 set a goal of creating no new space debris by 2030, and more than 100 institutions and companies are reported to have signed it. Even so, the charter is centered mainly on Earth orbit.
Applied together with the United Nations Committee on the Peaceful Uses of Outer Space’s long-term sustainability guidelines, the scope should be expanded to the space around the Moon, and Artemis Accords member states should form a body to share registration, prior notification, and tracking information on Moon-crossing objects.
South Korea has no reason to remain merely an observer. The pre- and post-impact data collected by Danuri will be early empirical material for quantifying the risk of debris impacts. If the Korea AeroSpace Administration brings this data to the international table, it can secure a voice in the norm-setting process.
It would also be a way for a latecomer country to lead by implementing upper-stage disposal capability in the design of its under-development next-generation launch vehicle.
The 27-meter-diameter crater left on the Moon on the 5th could become the starting point for that discussion.