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Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies (2010)

Chapter: Appendix A: Independent Cost Assessment

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Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
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A
Independent Cost Assessment

The statement of task for the National Research Council’s (NRC’s) Committee to Review Near-Earth Object Surveys and Hazard Mitigation Strategies required it to “include an assessment of the costs of various alternatives, using independent cost estimating.” Science Applications International Corporation (SAIC) was contracted by the NRC to perform independent risk, cost, and schedule assessments in support of the committee. Eight projects were chosen by the committee for assessment. The SAIC assessment of the eight projects was led by Joseph Hamaker, with the assistance of SAIC senior scientists L. Cole Howard and Peter S. Gural.

The eight projects selected by the committee are meant to be viewed in this assessment as examples of activities that could be developed to accomplish the specified detection, characterization, or mitigation goals. Other particular solutions are certainly also plausible, but the ones selected for this assessment were deemed sufficiently illustrative for risk, cost, and schedule assessment. Although data from advocates of specific concepts were used as starting points, in all cases SAIC performed an independent analysis of the technology readiness, cost, and schedules of the missions.

The near-Earth object (NEO) survey, characterization, and mitigation approaches that the committee asked SAIC to assess were at various levels of definition and in some cases were largely conceptual. As a result, it is too early in the NEO program development and design of most of the eight representative projects for the committee to develop confidence in either the projects themselves or the SAIC’s cost estimates.

As one example, the committee notes the mission to place a 0.5-meter infrared telescope in a Venus-trailing orbit costed by a special team at the Jet Propulsion Laboratory (JPL). Internal analysis by JPL yielded a range of approximately $600 million to $650 million, including 5 years of operations and a 20 percent contingency, whereas the SAIC analysis yielded corresponding costs of $550 million to $1.8 billion.

The Large Synoptic Survey Telescope (LSST) is a second example in which, by contrast, the SAIC cost model predicts a significantly lower cost than the LSST team’s estimate. The LSST project estimated the construction budget at $390 million in 2007 dollars, whereas the SAIC cost range (for a replicate telescope, construction only) was between $140 million and $340 million in 2009 dollars.

These examples demonstrate that the initial cost estimates produced by SAIC for this study contain many uncertainties. It was not within the scope of this committee’s tasks to conduct the more thorough mission definitions required to produce more accurate cost estimates and, in particular, to resolve the above differences.

The committee concluded that the primary value of the technical and cost assessments of the eight projects was not to provide a cost estimate of the potential solutions, but to identify the technical maturity and requirements

Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
×

of these options. The eight projects chosen by the committee are shown in Table A.1. These include three ground-based telescope concepts for NEO detection, two space-based systems for NEO detection, one space-based NEO characterization mission, and two space-based NEO mitigation systems. The results are presented in a range of costs meant to give decision makers some idea of the inherent technological risks and the range of resources that might be required to undertake such projects. However, given the conceptual level of definition of many of these projects, the end points of the range of costs will very likely change significantly as the designs are matured.

A key issue in the cost and schedule assessment was that of ensuring that the cost and schedule estimates were as much as possible on an equal footing with one another despite the limited information available to the cost estimators for some of the projects. All of these cost and schedule estimates for the space- and ground-based activities employed cost and schedule risk analysis to try to achieve this equal footing. SAIC examined the major inputs to the cost model (including mass and power contingencies, heritage assumptions, technology readiness assumptions, etc.), compared these data with past data for similar missions where analogous historical missions existed, and made adjustments so that all missions were estimated on a “level playing field” to the extent feasible. SAIC cost and schedule estimates for each NEO project were also risk-adjusted using a risk rating approach. SAIC assessed technology readiness at the major subsystem level and provided an assessment of the critical technologies on the basis of information provided to the estimators.

The results of the SAIC assessment were reviewed by the committee, and significant differences, both plus and minus, were noted between the numbers produced by the SAIC cost modeling tools and the project team estimates as described in part above.

A second issue facing the committee was to decide how much time and money should be spent having SAIC reconcile the significant differences between the estimates produced by the SAIC assessment and the project team estimates. The committee decided that, based on the dispersions in the level of maturity of the eight projects, it was premature to attempt this reconciliation.

TABLE A.1 Activities and Projects Evaluated by the Study’s Independent Cost Assessment

Activity/Project

Description

Status

Panoramic Survey Telescope and Rapid Response System

(PanSTARRS 4, or PS4)

4 × 1.8 m ground-based optical telescope for NEO detection either at Mauna Kea or Haleakala, Hawaii.

PS1 existing. For NEO, a replicate of planned

PS4 is assumed.

Large Synoptic Survey Telescope

(LSST)

1 × 8.4 m ground-based optical telescope for NEO detection at Cerro Pachon, Chile.

Planned. For NEO, a replicate is assumed.

Binocular Telescope

(Catalina Sky Survey II)

6 × 1.8 m ground-based optical telescope for NEO detection at Mount Hopkins, Arizona.

Planned. For NEO, a replicate is assumed.

0.5-meter Infrared Space Telescope

1 × 0.5 m space-based telescope for NEO detection at L1.

Proposed.

0.5-meter Infrared Space Telescope

(Ball Aerospace and Technologies Corporation NEO Survey)

1 × 0.5 m space-based telescope for NEO detection in a Venus-trailing orbit.

Proposed.

Don Quijote

(European Space Agency, or ESA)

A spacecraft orbiter/observer and an impactor spacecraft for NEO characterization and kinetic impact mitigation.

Proposed (not active in ESA).

Gravity tractor

A spacecraft orbiter that uses the gravitational field between itself and the NEO to mitigate NEO orbit.

Proposed.

Nuclear deflector

A spacecraft orbiter/observer and a nuclear deflector spacecraft for NEO mitigation. The observer spacecraft is assumed to be characterized by the Don Quijote orbiter.

Proposed.

Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
×

The cost risk results from the SAIC models for each mission or activity are presented in the form of cost S curves (confidence level versus cost). At this point, any comparably risk-adjusted cost can be selected from the S curves for each of the proposed projects. Choosing a single confidence level tends to automatically normalize the cost estimates across competing missions in a way that allows them to be directly compared. However, as previously stated, the entire range of each S curve should be considered more representative of possible outcomes given the current state of knowledge, and in fact most probable ranges of costs will also likely shift as the design concepts mature.

Major Cost-Analysis Assumptions

Understanding cost estimates requires an appreciation of the cost-estimating assumptions that were made. Some of the more important assumptions in this assessment were as follows:

  • The range of costs reported in this study included total life-cycle cost composed of pre-implementation costs (i.e., Phase A conceptual design and Phase B preliminary design), full-scale development/implementation (i.e., Phase C detailed design, Phase D production), and mission operations and data analysis (i.e., Phase E operations). Collectively, the Phase A through D costs are generally referred to as acquisition costs, the terminology that was used in this study.

  • All costs quoted in this report have been adjusted to 2010 prices using the NASA New Start Inflation Index.

  • Cost estimates of spaceflight missions are assumed to be NASA-funded and include an allowance for NASA civil service labor cost and other NASA institutional costs such as center management and operations and NASA general and administrative overhead (NASA “full costs”).

  • Ground-based observatories were assumed to be funded outside of the NASA full-cost institution and management model.

Methodology for Estimating the Range of Cost and Schedule for Ground-Based Facilities

The three ground-based missions were all optical observatories; the costs for them were estimated using the Multivariable Parametric Cost Model for Ground Optical Telescope Assemblies (in “References,” below, see the subsection “Cost Models”). As a cross-check, the results from the Multivariable Parametric Cost Model for Ground Optical Telescope Assembly Model were compared to ground-based telescope analogies.

Just as with spaceflight projects, there are a number of basic cost considerations in estimating the cost of ground-based facilities and research activities. These include the state of technology—technology varies considerably among industries and thus affects the accuracy of estimates. For a “first-of-a-kind” facility project, there is a lower level of confidence that the execution of the project will be successful (all else being equal). The inherent risk and uncertainty across the range of NEO ground-based activities is not constant. Some of the ground-based facilities have more challenging scientific goals, engineering requirements, and programmatic objectives. All cost and schedule estimates for the ground-based activities employed cost risk analysis to normalize for this is at the 99th percentile, but the Panoramic Survey Telescope and Rapid Response System 4 (PanSTARRS 4, or PS4), and the Binocular Telescope are also high, at the 80th and 75th percentile, respectively. The technology readiness of the telescopes was used to translate to the new design percentage.

Methodology for Estimating the Most Probable Range of Cost and Schedule for Space-Based Missions

The five space-based missions included two infrared telescopes, a kinetic characterization/kinetic impact mission, a gravity tractor, and a nuclear deflector mission. All of these space-based missions were estimated using the NASA QuickCost model (in “References,” see the subsection “Cost Models”). QuickCost is a model developed for NASA by SAIC that requires only a top-level description of the projects being estimated to generate

Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
×

risk-adjusted life-cycle cost and schedule estimates. QuickCost was also used to estimate the development span that would be expected for missions of the space-based missions’ size and complexity.

The QuickCost database includes approximately 100 data fields on more than 120 past space science flight projects. QuickCost provides means, medians, standard deviations, and coefficients of variation and interquartile ranges for all 100 descriptive parameters in the model’s database. SAIC examined “cross-parameter” trends to spot outlying technical descriptions for the missions being estimated. Missions with parameter relationships that lie outside these norms were flagged for further attention to determine if there is some underlying difference in assumptions or other bias in the mission descriptions. As a result of this exercise, some missions were found to have data voids such as total spacecraft masses, power, data rates, design lives, new design percentage, and instrument complexity. In these cases, SAIC estimated the parameters.

For the launch cost of the space-based missions, SAIC used the NASA Expendable Launch Services Model. (In “References,” see “Cost Models.”) This model estimates launch cost as a function of payload mass, destination (i.e., orbital inclination or escape), and payload shroud (fairing) size.

Most Probable Range of Cost and Schedule for the Eight Projects

A range of costs was estimated for each of the eight projects, following along with the project description including technology development requirements, technology readiness, and risk rating.

The S curves of a potential range of costs for each concept are provided in Figures A.1 through A.8. These present a top-level snapshot at this stage of the independent cost-estimating process of each concept’s range of potential budgeting requirements. Given the conceptual level of definition at this stage of the project development and the fact that the reconciliation between the project team and model estimates has not been performed, clearly the end points of this range for most of the projects also have a high probability of changing as the designs become more defined and the basis for the difference in current estimates is understood.

FIGURE A.1 Panoramic Survey Telescope and Rapid Response System (PanSTARRS 4) cost S curve.

FIGURE A.1 Panoramic Survey Telescope and Rapid Response System (PanSTARRS 4) cost S curve.

Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
×
FIGURE A.2 Large Synoptic Survey Telescope (LSST) cost S curve.

FIGURE A.2 Large Synoptic Survey Telescope (LSST) cost S curve.

FIGURE A.3 Catalina Sky Survey II (CSS) Binocular Telescope cost S curve.

FIGURE A.3 Catalina Sky Survey II (CSS) Binocular Telescope cost S curve.

Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
×
FIGURE A.4 0.5-meter Space-Based Infrared Telescope cost S curve.

FIGURE A.4 0.5-meter Space-Based Infrared Telescope cost S curve.

FIGURE A.5 0.5-meter Infrared Space-Based Telescope (Ball Aerospace and Technologies Corporation Survey) cost S curve.

FIGURE A.5 0.5-meter Infrared Space-Based Telescope (Ball Aerospace and Technologies Corporation Survey) cost S curve.

Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
×
FIGURE A.6 Don Quijote (European Space Agency) cost S curve (orbiter + impactor).

FIGURE A.6 Don Quijote (European Space Agency) cost S curve (orbiter + impactor).

FIGURE A.7 Gravity tractor cost S curve.

FIGURE A.7 Gravity tractor cost S curve.

Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
×
FIGURE A.8 Nuclear deflector cost S curve (orbiter + detonator).

FIGURE A.8 Nuclear deflector cost S curve (orbiter + detonator).

REFERENCES

Arecibo Observatory

Matthews, Christine M. 2009. The Arecibo Ionospheric Observatory. Report R40437. Congressional Research Service, Washington, D.C. March 5.

Catalina Sky Survey Binocular Telescope

Beshore, Edward, Catalina Sky Survey, University of Arizona Lunar and Planetary Laboratory. 2009. Surveying for Near Earth Objects with Small Binocular Telescopes. Presentation to the Survey/Detection Panel of the Committee to Review Near-Earth-Object Surveys and Hazard Mitigation Strategies, April 20.

Catalina Sky Survey Team, University of Arizona Lunar and Planetary Laboratory. 2009. The Catalina Sky Survey II: Surveying for Near-Earth Objects with Small Binocular Telescopes. Tucson, Ariz. March 20.

Larson, S., E. Beshore, A. Boattini, A. Gibbs, A. Grauer, R. Hill, and R. Kowalski, University of Arizona; and R. McNaught, G. Garradd, and D. Burton, Australian National University. 2009. The Catalina Sky Survey for NEOs. Presentation to the Survey/Detection Panel of the Committee to Review Near-Earth-Object Surveys and Hazard Mitigation Strategies, April 20.

Construction Cost Geographical Area Cost Adjustments

U.S. Army Corps of Engineers. 2009. Department of Defense data from PAX Newsletter No 3.2.1, 5 March 2009, DOD Area Cost Factors (ACF), Table—B, Part I and II (US and Foreign Locations). Available at http://www.usace.army.mil/CaEI/Documents/2009%20PAX%20Newsletter%203.2.1%20ACF%20Tables,%20dated%205%20Mar%202009.pdf.

Cost Models

NASA Headquarters Cost Analysis Division. 2009. QuickCost: A Spacecraft Cost Model, Version 4.2. Developed and maintained for NASA by SAIC. June.

Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
×

NASA Headquarters Cost Analysis Division. 2009. ELV Pricing Model, Version 1.0. Developed and maintained for NASA by SAIC. March.

Stahl, Philip H., Ginger Holmes Rowell, Gayle D. Reese, and Alicia Byberg, NASA Marshall Space Flight Center. 2005. Multivariable Parametric Cost Model for Ground Optical Telescope Assembly. International Society for Optical Engineering, Bellingham, Wash. August.

Don Quijote

Gálvez, Andrés, Strategic Studies and Institutional Matters Office, European Space Agency. 2009. ESA’s Studies on NEO Precursor Missions. Presentation to the Mitigation Panel of the Committee to Review Near-Earth-Object Surveys and Hazard Mitigation Strategies, June 24.

Gravity Tractor

Lu, Edward T., and Stanley G. Love. 2005. Gravitational tractor for towing asteroids. Nature 438:177-178.

Schweickart, Russell L. 2007. Technical Critique of NASA’s Report to Congress and of Associated “2006 Near-Earth Object Survey and Deflection Study: Final Report” Published Dec. 28, 2006. May 1.

Schweickart, Russell L. 2009. NEO Deflection. Presentation to the Mitigation Panel of the Committee to Review Near-Earth-Object Surveys and Hazard Mitigation Strategies, March 30-31.

Schweickart, Russell L. 2009. Briefing Paper on NEO Deflection. Prepared for the Mitigation Panel of the Committee to Review Near-Earth-Object Surveys and Hazard Mitigation Strategies Meeting, March 30.

Yeomans, D.K., S. Bhaskaran, S.B. Broschart, S.R. Chesley, P.W. Chodas, M.A. Jones, and T.H. Sweetser. 2008. Near-Earth Object (NEO) Analysis of Transponder Tracking and Gravity Tractor Performance. Jet Propulsion Laboratory, California Institute of Technology, Pasadena, Calif. September 1.

Infrared Telescope

Mainzer, Amy, Jet Propulsion Laboratory, California Institute of Technology. 2009. Space-Based Infrared NEO Observation Platforms. Presentation to the Survey/Detection Panel of the Committee to Review Near-Earth-Object Surveys and Hazard Mitigation Strategies, January 29.

Reitsema, Harold, Ball Aerospace and Technologies Corporation. 2009. The NEO Survey Concept. Presentation to the Committee to Review Near-Earth-Object Surveys and Hazard Mitigation Strategies, April 20.

Large Synoptic Survey Telescope (LSST)

Chesley, Steve, Jet Propulsion Laboratory, California Institute of Technology. 2008. NEO Surveying with the Large Synoptic Survey Telescope. Presentation to the Committee to Review Near-Earth-Object Surveys and Hazard Mitigation Strategies, December 10.

Heasley, J., R. Jedicke, and N. Kaiser, Institute for Astronomy, University of Hawaii. 2009. Program Concept for Detecting Hazardous Near-Earth Objects—The Large Array Synoptic Survey Telescope. Prepared for the Committee to Review Near-Earth-Object Surveys and Hazard Mitigation Strategies, March 20.

Ivezič, Z., University of Washington, et al., for the LSST Collaboration. 2008. LSST: From Science Drivers to Reference Design and Anticipated Products, Version 1.0. May 15. Available at http://lanl.arxiv.org/abs/0805.2366v1.

Ivezič, Z., J.A. Tyson, R. Allsman, J. Andrew, R. Angel, T. Axelrod, J.D. Barr, et al. for the LSST Collaboration. 2009. LSST’s NEO Survey Capabilities. Presentation to the Survey/Detection Panel of the Committee to Review Near-Earth-Object Surveys and Hazard Mitigation Strategies, January 28.

Nuclear Deflector

Adams, Robert B., NASA. 2009. Continuing Efforts at NASA MSFC Regarding Near Earth Objects. Presentation to the Mitigation Panel of the Committee to Review Near-Earth-Object Surveys and Hazard Mitigation Strategies, March 30.

Adams, R., J.W. Campbell, R.C. Hopkins, W.S. Smith, W. Arnold, J. Sverdrup, M. Baysinger, et al. 2007. Near Earth Object (NEO) Mitigation Options Using Exploration Technologies. Presented at the Planetary Defense Conference, March 5-8, Washington, D.C.. Available at http://www.nss.org/resources/library/planetarydefense/.

Hanrahan, Robert, National Nuclear Security Administration. 2009. Nuclear Explosives for NEO Deflection. Presentation to the Mitigation Panel of the Committee to Review Near-Earth-Object Surveys and Hazard Mitigation Strategies, March 30.

Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
×
Panoramic Survey Telescope and Rapid Response System (PanSTARRS)

Jedicke, Robert, Institute for Astronomy, University of Hawaii. 2008. Pan-STARRS: The Hunt Is on for NEOs. Presentation to the Survey/Detection Panel of the Committee to Review Near-Earth-Object Surveys and Hazard Mitigation Strategies, January 28.

Technology Readiness Levels and Risk Ratings

Mankins, John C., Advanced Concepts Office, Office of Space Access and Technology, NASA. 1995. Technology Readiness Levels: A White Paper. April 6.

Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
×
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Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
×
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Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
×
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Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
×
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Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
×
Page 107
Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
×
Page 108
Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
×
Page 109
Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
×
Page 110
Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
×
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Suggested Citation:"Appendix A: Independent Cost Assessment." National Research Council. 2010. Defending Planet Earth: Near-Earth-Object Surveys and Hazard Mitigation Strategies. Washington, DC: The National Academies Press. doi: 10.17226/12842.
×
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The United States spends approximately $4 million each year searching for near-Earth objects (NEOs). The objective is to detect those that may collide with Earth. The majority of this funding supports the operation of several observatories that scan the sky searching for NEOs. This, however, is insufficient in detecting the majority of NEOs that may present a tangible threat to humanity. A significantly smaller amount of funding supports ways to protect the Earth from such a potential collision or "mitigation."

In 2005, a Congressional mandate called for NASA to detect 90 percent of NEOs with diameters of 140 meters of greater by 2020. Defending Planet Earth: Near-Earth Object Surveys and Hazard Mitigation Strategies identifies the need for detection of objects as small as 30 to 50 meters as these can be highly destructive. The book explores four main types of mitigation including civil defense, "slow push" or "pull" methods, kinetic impactors and nuclear explosions. It also asserts that responding effectively to hazards posed by NEOs requires national and international cooperation. Defending Planet Earth: Near-Earth Object Surveys and Hazard Mitigation Strategies is a useful guide for scientists, astronomers, policy makers and engineers.

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