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Planetary Defense at NASA Press Kit National Aeronautics and Space Administration Planetary Defense at NASA Press Kit www.nasa.gov April 2019 Media Contacts NASA Headquarters Planetary Defense Coordination Office 300 E Street, SW Washington, DC 20546 JoAnna Wendel 202.358.1003 [email protected] Dwayne Brown 202.358.1726 [email protected] Key Organization Contacts Center for NEO Studies Paul Chodas – [email protected] Minor Planet Center Matthew Holman – [email protected] International Asteroid Warning Network James Bauer – [email protected] PLANETARY DEFENSE COORDINATION OFFICE Planetary Defense Coordination Office (PDCO) Hosted by the Planetary Science Division of the Science Mission Directorate at NASA Headquarters, Washington, DC PDCO’S ROLE • Characterizing those objects to • Provides early detection of Potentially determine their orbit trajectory, size, Hazardous Objects (PHOs)—the shape, mass, composition, rotational subset of Near-Earth Objects (NEOs), dynamics and other parameters, so both asteroids and comets, whose that experts can determine the severity orbits come within 5 million miles of the potential impact event, warn of of Earth’s orbit; and of a size large its timing and potential effects, and enough (larger than 30 to 50 meters) determine the means to mitigate the to do damage at Earth’s surface; impact; and • Tracks and characterizes PHO’s and • Planning and implementation of issues warnings of the possible effects measures to deflect or disrupt an of potential impacts; object on an impact course with Earth, • Provides timely and accurate informa- or to mitigate the effects of an impact tion on PHO’s to governments and the that cannot be prevented. Mitigation public; and measures that can be taken on Earth • Leads efforts in coordinating U.S. to protect lives and property include government planning for response evacuation of the impact area and to an actual impact threat. movement of critical infrastructure. WHAT IS PLANETARY DEFENSE? WHAT IS A NEAR-EARTH OBJECT? Planetary defense is the term used to A Near-Earth Object (NEO) is an asteroid encompass all the capabilities needed to or comet whose orbit periodically brings detect the possibility and warn of poten- it within approximately 121 million miles tial asteroid or comet impacts with Earth, (195 million kilometers) of the Sun—that’s and then either prevent them or mitigate within about 30 million miles (50 million their possible effects on Earth. Planetary kilometers), of Earth’s orbit. defense involves: • Finding and tracking near-Earth Like the planets, all asteroids and comets objects that pose of hazard of orbit the Sun, although some asteroids impacting Earth; are also in orbit about planets or even 3 PLANETARY DEFENSE COORDINATION OFFICE larger asteroids. Some of the smaller sponsored NEO surveys have provided moons of other planets may be captured 98 percent of all NEO detections. asteroids. Most asteroids are in what is called “the main belt” between Mars and In 1992, NASA began conducting Jupiter. The vast majority of near-Earth scientific workshops and research into asteroids have come from the inner part the identification, characterization, and of the main belt where, over tens of tracking of NEOs, as well as into potential millions of years, their orbits were altered mitigation strategies. NASA reported that by the gravitational influence of Jupiter NEOs with a diameter greater than 0.62 and Mars, and some by mutual collisions. miles (1 kilometer) posed the greatest hazard to life on Earth and predicted that Although the vast majority of NEOs that an organized survey could identify most enter Earth’s atmosphere are so small NEOs of this size within a decade. they disintegrate before reaching the surface, those that are larger than around In 1998, Congress directed NASA to find, 98 to 164 feet (30 to 50 meters) in size characterize, and monitor 90 percent of may survive the descent and could cause the estimated 2000 asteroids and comets widespread damage in and around their that approach the Earth that are larger impact sites. than about 1 kilometer (about 2/3-mile) in size. This goal was met in 2011. A BRIEF HISTORY OF NASA’S PLANETARY DEFENSE COORDINATION OFFICE In 2005, Congress extended that goal to NASA established the Planetary Defense include 90% of the NEOs larger than 140 Coordination Office in January 2016 to meters in size by the end of 2020. A near- coordinate planetary defense efforts by impact of an asteroid this size could across NASA, with other US agencies, devastate a state-wide area. As of and with international partners, and to November 2018, 8,382 of those NEOs administer NASA’s Near-Earth Object have been found, but this is only one Observation Program which dates back third of the estimated total population to 1998. However, NASA has been study- of 25,000. ing near Earth objects (NEOs) since the 1970s. The agency now participates as a HOW WE SEARCH FOR NEOS key member in the International Asteroid Observers find and track NEOs using Warning Network (IAWN), recommend- ground-based, wide sky survey tele- ed by the United Nations Committee scopes around the world, along with on the Peaceful Uses of Outer Space contribution from NASA’s space-based (UN-COPUOS) as the unified response NEOWISE telescope. The basic method for all space-capable nations to address of finding NEOs is to look for objects the NEO impact hazard. To date, NASA- moving against the background of 4 PLANETARY DEFENSE COORDINATION OFFICE relatively fixed stars. Observers provide MINOR PLANET CENTER their data to a global database main- The Minor Planet Center (MPC) is the tained by the Minor Planet Center (MPC), internationally recognized public archive which is sanctioned by the International of small-body orbit data submitted by Astronomical Union for world-wide col- observers from around the world. The lection of observations and tracking of MPC notifies observers worldwide about asteroids and comets, and funded by NEO discoveries so that timely follow-up NASA’s NEO Observations Program. observations can be collected for identi- The Center of Near-Earth Object Studies fication and orbit computation. The MPC (CNEOS) uses the position data reported is sanctioned by the International Astro- to the MPC to calculate high precision nomical Union and supported by NASA’s orbits decades into the future and are NEO Observations Program as a tasked with warning PDCO of any subnode of NASA’s Planetary Data potential impacts. System Small Bodies Node. https://www.minorplanetcenter.net/iau/mpc.html Key Organizations Involved with PDCO CENTER FOR NEAR-EARTH OBJECTS IAWN—INTERNATIONAL ASTEROID STUDIES (CNEOS) WARNING NETWORK The Center for Near-Earth Object Studies The IAWN was established (in 2013) (CNEOS) computes high-precision orbit to foster an international group of paths for NEOs from positions reported astronomy and space institutions involved to the Minor Planet Center. CNEOS in exchange of data and information for computes orbits for new asteroid discov- detecting, tracking, and characterizing eries and performs long-term analyses NEOs. The IAWN is tasked with develop- of possible future positions of hazardous ing a strategy using well-defined asteroids relative to Earth to determine communication plans and protocols to and warn of any impact hazard. CNEOS assist Governments in the analysis of computes impact time and location in the asteroid impact consequences and in event of a predicted impact threat. The the planning of mitigation responses. Jet Propulsion Laboratory hosts CNEOS http://iawn.net/ for NASA’s NEO Observations Program, and its website makes all orbit computation information public. https://cneos.jpl.nasa.gov/ 5 PLANETARY DEFENSE COORDINATION OFFICE NEO Population—140 Meters and Larger > = 1 km > = 1 km Not Found Found 0.2% 3.7% 0.30 – 1 km 140 – 300 m Not Found Not Found 8.0% 57.2% 0.30 – 1 km Found 14.3% 140 – 300 m Found 16.6% NEO Survey Status Jan 2019 PlanetaryPlanetary Defense Defense Coordination Coordination Of Officefice Science Mission Directorate Planetary Science Division Center for NEO Studies Planetary Science Officer Program Administrator (Jet Propulsion Laboratory) Lindley Johnson LaJuan Moore Small Bodies Node (University of Maryland) Minor Planet Center (Smithsonian Astrophysical Observatory) Public Communications Professional/Public Outreach JoAnna Wendel Doris Daou Linda Billings Patricia Talbert NEO Observations Program Detection & Characterization Interagency Partnerships International Partnerships Kelly Fast, Program Manager Victoria Andrews, PE Rob Landis, PE Mike Kelley, Lead PS International Asteroid Warning Network (IAWN) Space Mission Planning Advisory Group (SMPAG) PE=Program Executive PS=Program Scientist Flight Projects Double Asteroid Redirection Test (DART) Gordon Johnston, PE Tom Statler, PS 6 PLANETARY DEFENSE COORDINATION OFFICE Fast Facts 7 .
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