Editing Asteroid impact avoidance (section)

=== History of US government mandates ===

Efforts in [[asteroid impact prediction]] have concentrated on the survey method. The 1992 NASA-sponsored Near-Earth-Object Interception Workshop hosted by [[Los Alamos National Laboratory]] evaluated issues involved in intercepting celestial objects that could hit Earth.<ref>{{cite journal|last1=Canavan|first1=G. H.|last2=Solem|first2=J. C.|last3=Rather|first3=D. G.|year=1993|title=Proceedings of the Near-Earth-Object Interception Workshop, January 14–16, 1992, Los Alamos, NM|journal= Los Alamos National Laboratory LA—12476-C|url= https://ntrs.nasa.gov/search.jsp?R=19930019383}}</ref> In a 1992 report to [[NASA]],<ref name="morrison_1992">Morrison, D., 25 January 1992, [https://archive.org/details/nasa_techdoc_19920025001 ''The Spaceguard Survey: Report of the NASA International Near-Earth-Object Detection Workshop''] {{webarchive |url=https://web.archive.org/web/20161013041451/https://archive.org/details/nasa_techdoc_19920025001 |date=October 13, 2016 }}, [[NASA]], Washington, D.C.</ref> a coordinated [[Spaceguard]] Survey was recommended to discover, verify and provide follow-up observations for Earth-crossing asteroids. This survey was expected to discover 90% of these objects larger than one kilometer within 25 years. Three years later, another NASA report<ref>Shoemaker, E.M., 1995, ''Report of the Near-Earth Objects Survey Working Group'', NASA Office of Space Science, Solar System Exploration Office</ref> recommended search surveys that would discover 60–70% of short-period, near-Earth objects larger than one kilometer within ten years and obtain 90% completeness within five more years.

In 1998, NASA formally embraced the goal of finding and cataloging, by 2008, 90% of all near-Earth objects (NEOs) with diameters of 1&nbsp;km or larger that could represent a collision risk to Earth. The 1&nbsp;km diameter metric was chosen after considerable study indicated that an impact of an object smaller than 1&nbsp;km could cause significant local or regional damage but is unlikely to cause a worldwide catastrophe.<ref name="morrison_1992"/> The impact of an object much larger than 1&nbsp;km diameter could well result in worldwide damage up to, and potentially including, [[Human extinction|extinction of the human species]]. The NASA commitment has resulted in the funding of a number of NEO search efforts, which made considerable progress toward the 90% goal by 2008. However the 2009 discovery of several NEOs approximately 2 to 3 kilometers in diameter (e.g. {{mp|2009 CR|2}}, {{mp|2009 HC|82}}, {{mp|2009 KJ}}, {{mp|2009 MS}} and {{mp|2009 OG}}) demonstrated there were still large objects to be detected.

United States Representative [[George Brown Jr.|George E. Brown Jr.]] (D-CA) was quoted as voicing his support for planetary defense projects in ''Air & Space Power Chronicles'', saying "If some day in the future we discover well in advance that an asteroid that is big enough to cause a mass extinction is going to hit the Earth, and then we alter the course of that asteroid so that it does not hit us, it will be one of the most important accomplishments in all of human history."<ref>{{Cite journal|last=France|first=Martin|date=7 August 2000|title=Planetary Defense: Eliminating the Giggle Factor|url=https://www.airuniversity.af.edu/Portals/10/ASPJ/journals/Chronicles/france2.pdf|journal=Air & Space Power Chronicles|volume=14|pages=12|via=Air University}}</ref>

Because of Congressman Brown's long-standing commitment to planetary defense, a U.S. House of Representatives' bill, H.R. 1022, was named in his honor: The George E. Brown Jr. Near-Earth Object Survey Act. This bill "to provide for a Near-Earth Object Survey program to detect, track, catalogue, and characterize certain near-Earth asteroids and comets" was introduced in March 2005 by Rep. [[Dana Rohrabacher]] (R-CA).<ref>[[National Academy of Sciences]]. 2010. Defending Planet Earth: Near-Earth Object Surveys and Hazard Mitigation Strategies: Final Report. Washington, DC: The National Academies Press. Available at: {{cite web|url=https://books.nap.edu/catalog.php?record_id%3D12842 |title=Browse All Topics {{pipe}} the National Academies Press |access-date=2016-10-02 |url-status=live |archive-url=https://web.archive.org/web/20140806153938/http://books.nap.edu/catalog.php?record_id=12842 |archive-date=2014-08-06 }}.</ref> It was eventually rolled into S.1281, the [[NASA Authorization Act of 2005]], passed by Congress on December 22, 2005, subsequently signed by the President, and stating in part:

{{blockquote|The U.S. Congress has declared that the general welfare and security of the United States require that the unique competence of NASA be directed to detecting, tracking, cataloguing, and characterizing near-Earth asteroids and comets in order to provide warning and mitigation of the potential hazard of such near-Earth objects to the Earth. The NASA Administrator shall plan, develop, and implement a Near-Earth Object Survey program to detect, track, catalogue, and characterize the physical characteristics of near- Earth objects equal to or greater than 140 meters in diameter in order to assess the threat of such near-Earth objects to the Earth. It shall be the goal of the Survey program to achieve 90% completion of its near-Earth object catalogue (based on statistically predicted populations of near-Earth objects) within 15 years after the date of enactment of this Act. The NASA Administrator shall transmit to Congress not later than 1 year after the date of enactment of this Act an initial report that provides the following: (A) An analysis of possible alternatives that NASA may employ to carry out the Survey program, including ground-based and space-based alternatives with technical descriptions. (B) A recommended option and proposed budget to carry out the Survey program pursuant to the recommended option. (C) Analysis of possible alternatives that NASA could employ to divert an object on a likely collision course with Earth.}}

The result of this directive was a report presented to Congress in early March 2007. This was an [[Analysis of Alternatives]] (AoA) study led by NASA's Program Analysis and Evaluation (PA&E) office with support from outside consultants, the Aerospace Corporation, NASA Langley Research Center (LaRC), and SAIC (amongst others).

See also [[Asteroid impact prediction#Improving impact prediction|Improving impact prediction]].