Forgotten Rocket to Hit the Moon: first debris, but not the last

A forgotten SpaceX rocket from 2015 is going to hit the moon next month. With a human presence soon to be established on the Moon and in its orbit, managing dangerous space debris is a responsibility we need to prioritize.

A SpaceX Falcon 9 upper-stage rocket first launched in 2015 is going to hit the far side of the moon next month. After delivering the DSCOVR mission to its intended orbit one million miles from Earth, there were few options for the spent rocket. Far from home and with no fuel left, this rocket could not be disposed of in the usual ways. Rockets that deliver missions far from Earth can’t be turned back around, so they are usually jetted even farther away, hopefully never to be seen again. For rockets that finish their mission closer to home, a small bump back toward Earth using the last fumes of fuel is usually enough to tumble them into Earth’s built in incinerator–the atmosphere. 

Rockets far from Earth with no fuel left have an unknown future ahead of them. They are left at the mercy of the Solar System’s gravitational forces and could end up virtually anywhere in the Sun-Earth-Moon system–including the lunar surface! A rocket running out of fuel isn’t rare. Just last year a Falcon 9 upper stage was seen breaking up over Portland three weeks after it ran out of fuel and was unable to burn up in the intended way. Next month, the Moon will gain another crater when the three-ton DSCOVR Falcon 9 upper-stage hits the lunar surface at over 5,700 miles per hour. Sounds impressive, but the crater will blend right in with the Moon’s other half a billion craters of the same size. NASA’s Lunar Reconaissance Orbiter will likely take “weeks to months” to identify the new crater, according to NASA.

This is the first time a large piece of space debris will hit the moon, but it will not be the last. As more missions fly similar paths, more rockets will end up stranded with no maneuverability and no clear fate. Many agencies are already working to avoid that outcome by developing rockets like ESA’s Atlas family and SpaceX’s Starship. The Atlas rockets are launched with extra fuel to send them out of the Earth-Moon system after delivering their mission to its intended orbit. The most recent successful mission for the Atlas rocket family was the delivery of the Webb telescope to its orbit of L2 a million miles away. SpaceX’s Starship rockets will be fully reusable and will use reserved fuel to turn around and land back on Earth.

​​“The upcoming Falcon 9 lunar impact illustrates well the need for a comprehensive regulatory regime in space, not only for the economically crucial orbits around Earth but also applying to the Moon,” says Holger Krag, Head of ESA’s Space Safety Program.
Although this unplanned crash is not a good example of responsible space debris practices, it is a first glance of what is sure to come in the near future. Using the Moon as a trash dump is actually far safer than leaving large debris unattended out in space. (Remember the opening scene in Gravity? That isn’t far from reality.) With NASA’s Artemis program set to return humans to the Moon by 2024 and establish a base camp for long-term stays, public and private interest in the Moon is sure to increase. Many of the rockets delivering these spacecraft will surely meet their fate on the lunar surface. Certain criteria will be ironed out by the space agencies to keep the debris in check, but these rockets are better left as rubble on the surface than dangerous, uncontrollable debris that threaten human missions to the Moon.