Plan: the National Aeronautics and Space Administration should substantially increase its efforts to survey Near Earth Objects including both ground- and space-based tracking measures.
The plan makes effective mitigation possible against all NEOs
NRC 2010 (National Research Council Committee to Review Near-Earth Object Surveys and Hazard Mitigation Strategies, “Defending Planet Earth: Near-Earth Object Surveys and Hazard Mitigation Strategies,” http://www.nap.edu/catalog.php?record_id=12842)
Combined ground- and space-based surveys have a number of advantages. Such surveys discover more NEOs of all sizes, including a substantial number smaller than 140 meters in diameter. These combined surveys alsoprovide more characterization data about the entire NEO population. With both infrared and visible data for most targets, it would be possible to obtain accurate diameter estimates for all objects, as well as measurements of their albedos and their surface and thermal properties. These high-value characterization data could help to guide mitigation campaign studies. Additionally, a dual survey provides much information on the population of objects smaller than 140 meters in diameter. Space-based sensors would find new objects and facilitate exploration
NAC 2010 (“Report of the NASA Advisory Council Ad Hoc Task Force on Planetary Defense,” Oct 6, http://www.nss.org/resources/library/planetarydefense/2010-NASAAdvisoryCouncilOnPlanetaryDefense.pdf)
2.1. NEO Search: To implement this recommendation, the Task Force recommends that NASA immediately initiate a space-based infrared telescopic NEO search project as the primary means of meeting the congressionally mandated George E. Brown NEO Survey goal. NASA was tasked to discover 90 percent of the NEOs larger than 140 meters by the end of 2020 as part of the NASA Authorization Act of 2005 (Public Law No. 109-155). Both ground- and space-based options for meeting the George E. Brown, Jr. NEO Survey goals have been investigated. Although NASA should continue to assist state-of -the-art ground-based optical surveys, including those coming on line or planned by other agencies (e.g., PanSTARRS, LSST), one or more space-based infrared (IR) telescopes in an orbit interior to Earth’s (e.g., a Venus-like orbit) offers several search efficiency advantages. Compared with ground-based optical systems, such space-based systems possess greater discovery efficiency and can more accurately determine the sizes and orbits of potentially threatening objects. The cost of such a survey asset is comparable to the multiple dedicated ground-based alternatives required, and will rapidly meet the legislated completion goal (probably within seven years). Additionally, a space-based survey, with its advantageous observing geometry and frequency, will enable prompt and precise orbit determination of newly discovered NEOs in collaboration with ground-based optical and radar systems, reducing the need for actual deflection campaigns. NASA should also examine the additional costs and observing advantages of a pair of such Venus-orbit survey telescopes, both to complete the overall survey more rapidly and aid in collapsing the error ellipse of worrisome NEOs. These enhanced capabilities may further reduce unnecessary launches of in situ tracking or deflection spacecraft. Although some NEOs are potentially hazardous, their periodic close approaches to Earth also make them among the most accessible objects in the solar system for robotic and human exploration. A space-based IR survey telescope would efficiently find both exploration targets and threatening NEOs currently inaccessible to observation by ground-based systems.
Deflection would be easy
BOTTKE et al 2004 (William F. Bottke, Jr., Southwest Research Institute; Alessandro Morbidelli, Observatoire de la Cˆote d’Azur; Robert Jedicke, University of Hawai’i; Mitigation Of Hazardous Comets And Asteroids, p. 1-2)
It is now generally accepted that impacts of large NEOs represent a hazard to human civilization. This issue was brought into focus by the pioneering work of Alvarez et al. (1980), who showed that the extinction of numerous species at the Cretaceous–Tertiary geologic boundary was almost certainly caused by the impact of a massive asteroid (at a site later identified with the Chicxulub crater in the Yucatan peninsula) (Hildebrand et al. 1991). Today, the United Nations, the US Congress, the European Council, the UK Parliament, the IAU, NASA, and ESA have all made official statements that describe the importance of studying and understanding the NEO population. In fact, among all worldwide dangers that threaten humanity, the NEO hazard may be the easiest to cope with, provided adequate resources are allocated to identify all NEOs of relevant size. Once we can forecast potential collisions between dangerous NEOs and Earth, action can be taken to mitigate the potential consequences.
Asteroid risks are unique—it’s the only disaster we can totally avoid
Morrison 2005 - NASA Astrobiology Institute (David, “ Defending the Earth Against Asteroids: The Case for a Global Response ” http://www.princeton.edu/sgs/publications/sgs/pdf/13%201-2%20Morrision.pdf Science and Global Security, 13:87–103 )
No asteroids have been discovered so far that threaten an impact over the next several centuries. Of course, we can say nothing about possible hits from the undiscovered fraction of the NEA population. These surveys are deemed to be worthwhile because we have the technology, atleast in principle, to deflect a threatening asteroid, given decades of warning. The impact hazard is unique in that it is possible to avoid the damage entirely. In most natural hazard areas, “mitigation” consists of ways to plan for a disaster or to deal with the disaster after it happens. Only in the case of cosmic impacts can we develop mitigation plans with the objective of avoiding the disaster itself.