In April 2023, the United States government released the National Preparedness Strategy and Action Plan for Near-Earth Object Hazards and Planetary Defense to improve the nation’s readiness to address the threat of near-Earth object (NEO) impacts over the next decade. In response, NASA has developed its own Planetary Defense Strategy and Action Plan to focus the agency’s efforts and chart a path forward for planetary defense activities.
Near-Earth objects are asteroids and comets that orbit the Sun and come within 30 million miles of Earth’s orbit. They range in size from small meteoroids just a few meters across to much larger bodies several kilometers wide. While most small NEOs harmlessly disintegrate in Earth’s atmosphere, larger objects have the potential to cause significant local damage or even global devastation upon impact.
NASA has been studying NEOs since 1998 and formalized its planetary defense work in 2016 with the establishment of the Planetary Defense Coordination Office (PDCO). The PDCO oversees ongoing NEO research and coordinates activities with other U.S. agencies and international partners. In 2022, the National Academy of Sciences prominently featured planetary defense in its decadal survey, noting the PDCO’s critical role in advancing U.S. capabilities.
Despite impressive progress in NEO detection in recent years, several key challenges remain that NASA’s strategy aims to address:
- Survey, detection, characterization and assessment: Improving capabilities to find and understand potentially hazardous NEOs. The upcoming NEO Surveyor mission will drastically accelerate detection rates when launched in 2028.
- Mitigation: Advancing technologies for reconnaissance and deflection/disruption demonstration missions to be better prepared for an actual threat. The DART mission’s successful asteroid impact in 2022 was a major milestone.
- International cooperation: Fostering greater global collaboration as international NEO survey and mitigation capabilities expand. NASA plans to continue its leadership role in coordinating worldwide efforts.
- Interagency coordination: Spearheading ongoing coordination of planetary defense activities across the U.S. government to develop a stable, long-term national capability as called for in the National Strategy.
- NASA organization: Ensuring planetary defense efforts have sufficient support and priority within NASA’s Planetary Science Division and the agency as a whole to expand key activities.
- Strategic communications: Better integrating and disseminating information about NASA’s NEO survey and mitigation work to raise awareness and preparedness.
To achieve its objectives, NASA’s Planetary Defense Strategy outlines eight high-level strategic goals, each with specific near-term, mid-term and long-term actions:
Goal 1: Enhance NEO detection, tracking, and characterization capabilities
- Leverage existing and planned assets to accelerate NEO discovery
- Advance technologies to improve determination of NEO properties
- Continue efforts to detect small asteroids entering Earth’s atmosphere
Goal 2: Improve coordination on NEO modeling, prediction, and information integration
- Support interagency NEO impact modeling working group
- Develop suite of validated simulation tools for deflection/disruption
- Create impact risk assessment data pipeline for decision makers
Goal 3: Develop technologies for NEO reconnaissance, deflection and disruption
- Design rapid-response reconnaissance mission concepts
- Conduct studies of various deflection/disruption approaches
- Continue research on nuclear explosive device application when needed
- Plan follow-on flight demonstrations to DART
Goal 4: Increase international cooperation on NEO preparation
- Engage foreign governments to promote collaborative approach
- Demonstrate leadership in technical international NEO organizations
- Strengthen International Asteroid Warning Network and Space Mission Planning Advisory Group
- Explore opportunities to participate in other nations’ NEO missions
Goal 5: Coordinate with FEMA and others to strengthen NEO impact emergency procedures
- Develop realistic exercise scenarios based on credible impact threats
- Improve notification protocols for government and public communications
- Establish benchmarks for recommending reconnaissance and deflection/disruption responses
Goal 6: Enhance NASA’s ongoing interagency coordination efforts
- Convene regular interagency meetings to monitor progress on National Strategy
- Identify key agency points of contact for NEO issues
- Explore leveraging existing authorities to facilitate interagency collaboration
Goal 7: Review NASA’s organizational structure for planetary defense
- Conduct independent assessment of planetary defense activities and organization
- Formulate budget and plans to sustain and grow key efforts
Goal 8: Bolster strategic communications related to planetary defense
- Prepare communications plan including for potential impact threats
- Increase leadership visibility of planetary defense in public messaging
By focusing resources and efforts in these areas, NASA seeks to significantly improve national capabilities over the next decade to detect, track, and characterize potentially hazardous NEOs, and to effectively respond to an actual impact threat if necessary. The strategy builds upon the agency’s successful NEO research and technology development to date, including the DART mission, while fostering greater collaboration both domestically and internationally.
With the frequency of potential NEO impacts, it is not a matter of if, but rather when Earth will face its next significant asteroid threat. Through its Planetary Defense Strategy and Action Plan, NASA is committed to advancing the scientific understanding and technical capabilities needed to protect Earth and its inhabitants from this rare but potentially catastrophic natural hazard. As more nations develop NEO survey and mitigation capabilities of their own in the coming years, NASA will continue to provide leadership in coordinating and conducting planetary defense efforts on a global scale.
While much work remains to be done, the U.S. National Strategy and NASA’s Planetary Defense Strategy together provide a comprehensive roadmap for improving humanity’s readiness to address the NEO impact hazard. By making strategic investments now in NEO detection, modeling, technology development, and emergency preparedness, NASA and its partners can help ensure society is adequately prepared to respond when the next significant asteroid threat is discovered. Continued public engagement and support will be vital as planetary defense efforts expand, laying the foundation for a more resilient future.
