SpaceX is preparing for the first orbital test flight of its Starship launch system, the largest and most powerful rocket ever developed, amid concerns from experts about the potential risks of a catastrophic failure and the resulting debris in low-Earth orbit.
The 14th test flight of the Starship system, which consists of a 72-meter Super Heavy first-stage booster and a 52-meter Starship upper stage, was initially scheduled for August but is now expected in mid-September pending final approval from the U.S. Federal Aviation Administration (FAA). This flight marks the first attempt to reach orbit after previous tests achieved only suborbital trajectories.
Moriba Jah, a professor of aerospace engineering at the University of Texas at Austin, warned that an explosion of the Starship upper stage while in orbit could generate a debris field larger than any previous in-orbit event, including the 2021 Russian anti-satellite missile test that destroyed the Cosmos-1408 satellite. This incident produced around 1,500 trackable fragments and many more smaller pieces, significantly impacting operations such as SpaceX’s Starlink satellite network.
“If something like that happened in low-Earth orbit, it would be like the Russian anti-satellite test, but probably a few scales larger in terms of debris,” Jah said. Such debris could threaten other satellites, spacecraft, and potentially human spaceflight by increasing collision risks.
Ella Atkins, an aerospace engineering professor at Virginia Tech, noted that the highest risk of explosion lies with the booster, which does not reach orbit. Once in orbit, collision risks emerge if orbits are not coordinated, making careful management and collaboration essential to preventing debris-generating incidents. She emphasized that the velocity required for orbit means any collision could have serious consequences regardless of the objects’ size or mass.
The Starship system is designed for reusability, with both stages meant to be caught on Earth by a specialized tower after launch. The upper stage is intended to function in space, including as a human landing system variant selected by NASA for its Artemis program, which aims to return astronauts to the Moon. This mission will involve significant in-orbit refueling operations, raising additional concerns about traffic and safety management in low-Earth orbit.
Space debris has become an increasing hazard to space activities. A study published in May highlighted incidents of damage caused by small debris, including impacts on the ESA Sentinel-1A satellite and China’s Shenzhou-20 spacecraft. The rise of mega-constellations, particularly SpaceX’s Starlink system with over 11,000 satellites, has exacerbated orbital congestion, generating hundreds of thousands of collision avoidance maneuvers annually.
Experts caution that the growing density of space objects raises the specter of the Kessler Syndrome, a chain-reaction of collisions potentially rendering certain orbits unusable. Jah advocates for enhanced international coordination akin to the regulatory framework managed by the International Telecommunication Union for wireless spectrum, proposing a more systematic approach to managing orbital carrying capacity.
Despite these concerns, the current geopolitical climate makes comprehensive space traffic governance challenging. The U.S., China, and Russia—dominant space powers—favor unrestricted operational freedom, complicating prospects for binding international agreements on debris mitigation and orbital management. The Outer Space Treaty, which holds states liable for damage caused by their space objects, provides a legal framework, but experts agree more practical mechanisms are needed as space activities accelerate.
As SpaceX moves forward with the Starship orbital test flight, the potential for a major debris event underscores the urgency of addressing space traffic coordination and the long-term sustainability of orbital operations.