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Overview of Active Planetary Defense Methods

  • David MorrisonEmail author
Chapter
Part of the Space and Society book series (SPSO)

Abstract

The two essential functions of planetary defense are to locate any asteroid on a collision course with Earth and to deflect or destroy it before it hits. Short-term warning and evacuation may be sufficient to protect populations from small asteroids. If active defense is required, we may either deflect the asteroid (change its orbit so that it misses the Earth or strikes in an uninhabited area such as oceans or deserts) or break it up far enough from Earth that the debris is dispersed and misses the planet. Most defense strategies involve deflection using spacecraft to intercept the asteroid, preferably several years before the predicted impact, to produce a change in its orbital period. The technologies that have been studied use kinetic impactors, nuclear explosives, or gravity tractors. None of these has been demonstrated yet, although the DART mission under development will test kinetic impact technology. Other suggestions, such as laser or solar heating or various slow-push options, are not technologically mature enough to be considered. Because dangerous impacts are exceedingly rare, with intervals of centuries or longer, we must also consider the potential unintended consequences or even deliberate misuse of premature development or deployment of planetary defense systems.

Keywords

Planetary defense Impact hazard Impact risk Kinetic impactor Gravity tractor Nuclear deflection 

References

  1. Ahrens, T. J., & Harris, A. W. (1992). Deflection and fragmentation of near-Earth asteroids. Nature, 360(6403), 429–433. doi: https://doi.org/10.1038/360429a0CrossRefGoogle Scholar
  2. Ahrens, T. J., & Harris, A. W. (1994). Deflection and fragmentation of NEAs. In GehrelsT. (Ed.), Hazards Due to Comets and Asteroids (pp. 897–928). Tucson: University of Arizona Press.Google Scholar
  3. Barbee, B. W., Syal, M. B., Dearborn, D., Gisler, G., Greenaugh, K., Howley, K. M., et al. (2018). Options and uncertainties in planetary defense: Mission planning and vehicle design for flexible response. Acta Astronautica, 143(August 2017), 37–61. doi: https://doi.org/10.1016/j.actaastro.2017.10.021CrossRefGoogle Scholar
  4. Canavan, G. H. (1994). Cost and benefit of near-Earth object detection and interception. In T. Gehrels (Ed.), Hazards Due to Comets and Asteroids (pp. 1157–1191). Tucson: University of Arizona Press.Google Scholar
  5. Chapman, C. R., Durda, D. D., & Gold, R. E. (2001). The comet/asteroid impact hazard, a systems approach. San Antonio, TX: Southwest Research Institute.Google Scholar
  6. Cheng, A. F., Rivkin, A. S., Michel, P., Atchison, J., Barnouin, O., Benner, L., et al. (2018). AIDA DART asteroid deflection test: Planetary defense and science objectives. Planetary and Space Science, 157, 104–115. doi: https://doi.org/10.1016/j.pss.2018.02.015CrossRefGoogle Scholar
  7. Chodas, P. (1999). Orbit uncertainties, keyholes, and collision probabilities. In Bulletin of the American Astronomical Society (Vol. 31, p. 1117).Google Scholar
  8. Gritzner, C., & Kahl, R. (2004). Mitigation technologies and their requirements. In M. Belton, T. Morgan, N. Samarasinha, & D. Yeomans (Eds.), Mitigation of Hazardous Comets and Asteroids (pp. 167–200). Cambridge University Press.Google Scholar
  9. Harris, A. W. (2018). Population and impact frequency of Tunguska-size NEAs (in press). Icarus.Google Scholar
  10. Harris, A. W., Canavan, G. H., Sagan, C., & Ostro, S. J. (1994). The deflection dilemma: Use vs. misuse of technologies for avoiding interplanetary hazars. In T. Gehrels (Ed.), Hazards Due to Comets and Asteroids (pp. 1145–1156). Tucson: University of Arizona Press.Google Scholar
  11. Harris, A. W., Barucci, M. A., Cano, J. L., Fitzsimmons, A., Fulchignoni, M., Green, S. F., et al. (2013). The European Union funded NEOShield project: A global approach to near-Earth object impact threat mitigation. Acta Astronautica, 90(1), 80–84. doi: https://doi.org/10.1016/j.actaastro.2012.08.026CrossRefGoogle Scholar
  12. Holsapple, K. (2004). About deflecting asteroids and comets. In M. Belton, T. Morgan, N. Samarasinha, & D. Yeomans (Eds.), Mitigation of Hazardous Comets and Asteroids (pp. 113–140). Cambridge University Press.Google Scholar
  13. Lu, E. T., & Love, S. G. (2005). Gravitational tractor for towing asteroids. Nature, 438(7065), 177.CrossRefGoogle Scholar
  14. Melosh, H. L., Nemenchinov, I. V., & Zetzer, Y. I. (1994). Non-nuclear strategies for deflecting comets and asteroids. In T. Gehrels (Ed.), Hazards Due to Comets and Asteroids (pp. 1111–1132). Tucson: University of Arizona Press.Google Scholar
  15. Milani, A., Chesley, S. R., Chodas, P. W., & Valsecchi, G. B. (2002). Asteroid close approaches: Analysis and potential impact detection. In W. F. Bottke (Ed.), Asteroids III (pp. 55–70). Tucson: University of Arizona Press.Google Scholar
  16. Morrison, D. (2005). Defending the Earth Against Asteroids: The Case for a Global Response. Science & Global Security, 13(1–2), 87–103.CrossRefGoogle Scholar
  17. Morrison, D., & Teller, E. (1994). The Impact Hazard: Issues for the Future. In T. Gehrels (Ed.), Hazards due to Comets and Asteroids (pp. 1135–1143). Tucson: University of Arizona Press.Google Scholar
  18. Morrison, D., Harris, A. W., Sommer, G., Chapman, C. R., & Carusi, A. (2002). Dealing with the impact hazard. In W. F. Bottke (Ed.), Asteroids III (pp. 739–754). Tucson: University of Arizona Press.Google Scholar
  19. Sagan, C., & Ostro, S. J. (1994). Long-range consequences of interplanetary collisions. Issues in Science and Technology, 10(4), 67–72.Google Scholar
  20. Schweickart, R. L. (2004). The real deflection dilemma. In AIAA Planetary Defense Conference (p. AIAA-2004-1467).Google Scholar
  21. Shapiro, I. I., Vilas, F., A’Hearn, M., Cheng, A. F., Abell, P., Benner, L. a. M., et al. (2010). Defending Planet Earth. Washington, D.C.: National Academies Press. doi: https://doi.org/10.17226/12842
  22. Simonenko, V., Nogin, V., Petrov, D., Shubin, O., & Solem, J. C. (1994). Defending the Earth against impacts from large comets and asteroids. In T. Gehrels (Ed.), Hazards Due to Comets and Asteroids (pp. 929–954). Tucson: University of Arizona Press.Google Scholar
  23. Solem, J. C. (2000). Deflection and disruption of asteroids on collision course with Earth. Journal of the British Interplanetary Society, 53, 180–196.Google Scholar
  24. Valsecchi, G. B., Milani, A., Gronchi, G. F., & Chesley, S. R. (2003). Resonant returns to close approaches: Analytical theory. Astronomy & Astrophysics, 408(3), 1179–1196.CrossRefGoogle Scholar

Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.NASA Ames Research CenterMountain ViewUSA

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