Spacecraft re-entry strategies: Meeting debris mitigation and ground safety requirements

Abstract Re-entry of space hardware into the atmosphere is a recommended technique for disposal of space hardware at end of life. However, while aerodynamic heating and loads will break a reentering object apart and a substantial fraction of the object's mass will be melted away, evidence shows that large and potentially hazardous fragments can survive re-entry and impact the Earth's surface. Standards and regulations are emerging that will limit the acceptable hazard and require that space hardware exceeding a survivability threshold be deorbited into a safe ocean area. The current paper provides an overview of re-entry breakup, presents on-the-ground evidence that large, hazardous objects survive, highlights current guidelines, and requirements to limit the hazard to people and property, and discusses how re-entry hazards are estimated.