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Planetary Defense Coordination Office

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Planetary Defense Coordination Office Near-Earth Object Observations Program The key element of NASA’s Planetary The MPC is sanctioned by the International National Aeronautics and Space Administration Defense effort is the Near-Earth Object Astronomical Union and supported by the (NEO) Observations Program, which is PDCO as an element of NASA’s Planetary composed of projects to find, track, and Data System. characterize NEOs. PREDICT THE ORBIT THE OBJECTIVE The Center for Near-Earth Object Studies The current congressionally directed (CNEOS) computes high-precision orbit objective of the NEO Observations paths for NEOs from positions reported to Program is to find, track, and characterize the MPC. CNEOS computes orbits for new at least 90 percent of the predicted number asteroid discoveries and performs long- of NEOs that are 140 meters and larger in term analyses of possible future positions size - larger than a small football stadium of hazardous asteroids relative to Earth to - and to characterize a subset represen- determine and warn of any impact hazard. tative of the entire population. Objects of CNEOS computes impact time and loca- this size and larger pose a risk to Earth of tion in the event of a predicted impact. The greatest concern due to the level of devas- Jet Propulsion Laboratory hosts CNEOS tation an impact would cause, and should for the NEO Observations Program, and its continue to be the focus of global search website makes all orbit computation public. efforts. While no known asteroid larger than 140 meters in size has a significant CHARACTERIZE THE RISK chance to hit Earth for the next 100 years, The more that is known about a particular only about 40% of those asteroids have asteroid, the better it can be determined been found to date. what effects an impact might cause and what sort of damage might occur. The FIND AND OBSERVE Asteroid Threat Assessment Project at The NEO Observations Program sponsors NASA Ames predicts if an asteroid might projects that make use of telescopes disintegrate in Earth’s atmosphere or reach around the world to search for NEOs, track the surface and determines the level of them across the sky to determine their potential damage to inform a strategy for a orbits, and gain information on their sizes, response. Any possible in-space deflection shapes, and composition. mission would depend on the asteroid’s physical characteristics such as size, The Minor Planet Center (MPC) is the shape, density, and composition. NASA’s internationally agreed-to public archive of NEO Observations Program supports small-body orbit data submitted by research aimed at characterizing NEOs observers from around the world. The through telescopic measurements, MPC notifies observers worldwide about measurements made with radar telescopes, NEO discoveries so that timely follow-up and analyses of meteorites found on Earth. observations can be collected for identification, and orbit computation. National Aeronautics and Space Administration Headquarters Planetary Defense 300 E. Street, SW Washington, DC 20546 Coordination Office www.nasa.gov MITIGATE The PDCO sponsors studies of technol- ogies and techniques for deflecting an The PDCO is managed within the asteroid off a predicted impact course with Planetary Science Division of the Earth. It is developing missions to Science Mission Directorate at demonstrate those technologies and NASA Headquarters in Washington, D.C. determine their effectiveness in the event that these techniques must be utilized PDCO Responsible Official against a predicted asteroid impact threat. Mr. Lindley Johnson Planetary Defense Officer COORDINATE NASA Headquarters Chelyabinsk Meteor Bennu Radar Image of Itokawa The PDCO works with other government NASA 2012 JO25 JAXA Arecibo/NSF/NASA agencies to develop and update a National NEOO Responsible Official NEO Preparedness Strategy and Action Dr. Kelly Fast Plan. The PDCO also provides expert NEO Observations Program Manager NASA’s Planetary Defense Coordination Office input on the nature and effects of asteroid NASA Headquarters impacts to the Federal Emergency Near-Earth objects (NEOs) are asteroids • Plays a lead role in coordinating U.S. Management Agency (FEMA), so that For more information, visit: and comets that orbit the Sun like the government planning for response to an adequate emergency response can be https://www.nasa.gov/planetarydefense planets, but their orbits can bring them into actual impact threat. prepared in the event of a PHO impact https://solarsystem.nasa.gov Earth’s neighborhood - within 30 million that is not possible to avoid. https://cneos.jpl.nasa.gov miles of Earth’s orbit. NEOs are of great FIND https://www.minorplanetcenter.net interest to the scientific community, but The PDCO sponsors projects through its The PDCO also coordinates efforts with planetary defense is “applied planetary Near-Earth Object (NEO) Observations the space agencies of other nations as a Cover Image science” to address the NEO impact hazard. Program that employ a variety of ground member of the multinational International Pan-STARRS and space based telescopes to search for Asteroid Warning Network and the Space University of Hawaii “Planetary Defense” encompasses all the NEOs, determine their orbits, and measure Missions Planning Advisory Group, under capabilities needed to detect the potential their physical characteristics. The PDCO is the endorsement of the United Nations and warn of asteroid or comet impacts studying possible space-based telescope Committee on the Peaceful Uses of with Earth, and then either prevent them or missions optimized for NEO search and Outer Space. otherwise mitigate their possible effects. characterization that could accelerate the NASA established the Planetary Defense discovery of the currently undetected NEOs. Coordination Office (PDCO) to manage its ongoing mission of planetary defense. WARN The PDCO is responsible to provide timely The PDCO: and accurate information to the govern- Catalina Sky Survey Pan-STARRS NASA’s Infrared Goldstone Radar • Provides early detection of potentially ment, the media, and the public on close University of Arizona University of Hawaii Telescope Facility (IRTF) NASA/JPL hazardous objects (PHOs) – the subset approaches to Earth by PHOs and any of NEOs whose orbits predict they will potential for impact. If any PHO is found come within 5 million miles of Earth’s to pose a significant chance of impacting orbit; and of a size large enough (30 to Earth (greater than 1 percent over the next 50 meters) to damage Earth’s surface; 50 years), the PDCO will provide notifica- • Tracks and characterizes PHOs and tion messages for NASA to send to the issues warnings of the possible Executive Office of the President, the U.S. effects of potential impacts; Congress, and other government • Provides timely and accurate departments and agencies. information on PHOs; and.
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