Summary

Potentially hazardous Near-Earth Objects (NEOs), including both asteroids and comets, pose serious risks to human and environmental security on Earth. International arrangements such as the International Asteroid Warning Network and the Space Mission Planning and Advisory Group exist as coordinating mechanisms to detect, characterize, and assess NEO threats, and to discuss and share information on possible ground and space-based threat responses and mitigation measures. However, the international political and legal environment is not currently adequate to deal with NEO threats. While some elements of international law, including space law, provide broad guidelines, necessary clarity is lacking. The international legal and political order does not have in place adequate safeguards, mechanisms for action, or the clear delineation of roles, rights, and responsibilities at the international level to respond to a NEO threat. Additionally, a number of stressors on rational decision-making exist and would degrade the quality of NEO threat responses. Stressors on the quality of decisions and actions in response to a NEO threat include the incentive to wait for further data about the NEO and a conflicting incentive to take immediate action and bold steps so as to immediately satisfy constituents and to feel some amount of control over the situation. Public distrust, misinformation, disinformation, and conspiracies are all also likely, and will degrade public reactions and stakeholder decisions. A number of steps can be taken now, while the NEO threat remains hypothetical yet likely. These steps are warranted so as to assure the best possible response when a real, actual NEO threat emerges.