Orbital and surface risks from rocket bodies: Physical challenges, interdisciplinary solutions

点击翻译按钮获取中文摘要

In April 2021, the attention of the world was focused on the uncontrolled re-entry of a Chinese Long March 5B rocket body. At over 20 tonnes, the rocket body's exceptional size prompted safety concerns, with the NASA Administrator accusing China of failing to meet responsible standards for space flight. But China denied any wrongdoing. It pointed out that the risk of casualties was low and accused NASA of hypocrisy, as uncontrolled rocket re-entries are common. Indeed, just one month earlier a SpaceX Falcon 9 rocket body had an uncontrolled re-entry over the Pacific Northwest, attracting considerable attention, with pieces found in Washington State.China is right that uncontrolled re-entries are common - and that is the problem. Launch states have long assumed that the surface area of Earth is so large that uncontrolled re-entries pose a vanishingly small risk to people. This assumption, in turn, has led states and companies to focus on reducing the costs of access to space, including through minimal regulations and disposable equipment.No country or company operating in space is truly being safe. While some are better than others in reducing the percentage of re-entries that are uncontrolled or limiting the mass in uncontrolled objects, all take gambles about whether a piece of their spacecraft will cause damage or casualties. Moreover, launch states take or allow these gambles with respect to the safety of the world's entire population - without letting the rest of the world have a say. Worse yet, our preliminary research indicates that the exported risk falls disproportionately on the states of the Global South. This project will investigate historical, present, and projected casualty risks from uncontrolled rocket body re-entries to understand how launch states export risks globally and to identify trends in those exports. This includes producing visualizations for policy makers that convey the global character of casualty risks through global hazard maps and using simulations to illustrate the low probability/high-consequence character of these risks. The project will also identify changes in domestic and international space law and policy that could dis-incentivize the discarding of large objects in orbit, while incentivizing safe and environmentally sustainable re-entry practices.