A safety panel highlighted the urgency of safely deorbiting the International Space Station (ISS) after it retires in 2030, warning of a catastrophe if the spacecraft were to make an uncontrolled reentry through Earth’s atmosphere.

NASA’s Aerospace Safety Advisory Panel (ASAP) urged the space agency to develop a space tug to deorbit the ISS, saying that the deorbit vehicle is “not optional,” according to Space Policy Online.

“The day will inevitably come when the Station is at the end of its life—and we may not be able to dictate that day—it is inconceivable to allow the Station to deorbit in an uncontrolled manner,” ASAP Chair Patricia Sanders said during a briefing at the panel’s third quarter meeting on Thursday. The ISS is “simply too massive and would pose extreme hazard to populations over a broad area of Earth. This needs to be resourced and resourced now if we are to avert a catastrophe.”