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A2 DelayLack of adequate lead time between detection and deflection will cause mission failure. Early warning is key.Barbee & Nuth 2009 Asteroid Impact Threats: Advancements in Asteroid Science to Enable Rapid and Effective Deflection Missions 1Brent William Barbee, M.S.E., and 2Joseph A. Nuth III, Ph.D. 1Aerospace Engineer and Planetary Defense Scientist, Emergent Space Technologies, Inc., Greenbelt, MD, USA, 2Senior Scientist for Primitive Bodies, Solar System Exploration Division, NASAís Goddard Space Flight Center, Greenbelt, MD, 20771, USA Journal of Cosmology, 2009, Vol 2, pages 386-410. Cosmology, October 31, 2009 Understanding the sequence of events during a hazardous NEO situation highlights the importance of rapid response. Figure 19 shows the hazardous NEO response timeline, with the major events time ordered from left to right. The seven major time intervals are colored red, orange, yellow, green, blue, indigo, and violet. The timeline begins with the detection of the NEO by observational assets. Then there is some time interval (red) during which the observations are collected and processed, improving the accuracy of the orbit determination for the NEO until the impending collision is confirmed or at least the probability of a collision becomes high enough to warrant action. One of the unanswered questions in planetary defense currently is what the probability of collision threshold for action should be. Assuming the NEO is determined to be a threat, the next event is the beginning of mission planning for the deflection of the NEO, which takes place during the orange time interval. It is during this interval that the NEO must be scientifically characterized. At present this would require a precursor scientific characterization mission be sent to the NEO, which would require substantial time. If there is not sufficient time between when the NEO is first detected and the time of undeflected Earth impact, then the precursor science mission might have to be omitted and a deflection mission designed and launched based only on our best guesses of the asteroid’s physical properties, a highly undesirable situation where the likelihood of mission failure is high. The proposed advancements in NEO science presented in a subsequent section herein would be of tremendous aid here. Once enough data has been collected and preliminary mission planning is complete, then the next interval begins (yellow) during which the spacecraft carrying the deflection system and the launch vehicle are constructed and made ready for deployment. Based on actual experience with this process, it can be lengthy. Every effort would be made to hasten this process during a NEO emergency, but rushing it too much might cause mistakes that would lead to fatal mission failure. After the deflection spacecraft launches, it will require time to rendezvous with the NEO (green) and position the deflection system appropriately (blue). While advancements in spacecraft propulsion technology can reduce the flight time to rendezvous with the NEO, the natural orbital mechanics (which we cannot change) is often the limiting factor. This is why early detection and characterization are so important. Finally, once the deflection system is positioned and ready it can be deployed on the NEO, imparting a deflection. The effects of the deflection have time to accumulate during the interval between when the deflection is applied and the time of undeflected Earth impact (indigo). Clearly the goal is to maximize this time interval (by pushing all the other events as far backwards along the timeline as possible in order to stretch out the indigo segment by compressing the preceding intervals). This provides the best chance for causing the incoming asteroid to miss the Earth. Any delay kills solvency.Richard Crowther, 2009 Ph.D. Science and Technology Facilities Council (STFC), Harwell Science and Innovation Campus, Chilton, Oxfordshire OX11 0QX, UK Journal of Cosmology, 2009, Vol 2, pages 411-418. Cosmology, October 31, 2009 Near Earth Object (NEO) Impact Threat: An International Policy Response A second aspect is when a decision should be made to launch a deflection mission, or otherwise. Although this is somewhat dependent upon the impactor scenario (i.e. the time we would have to make a decision and mount a deflection mission), experience tells us that it would be prudent to make this decision as soon as a credible threat has been identified. These criteria and thresholds would need to agreed in advance of implementation, and hence are an immediate, if not urgent, requirement. NASA = Normal MeansNASA is normal means.DAVID MORRISON 2010 Director, Carl Sagan Center for Study of Life in the Universe, SETI Institute Senior Scientist, NASA Ames Research Center “Impacts and Evolution: Protecting Earth from Asteroids1” PROCEEDINGS OF THE AMERICAN PHILOSOPHICAL SOCIETY VOL. 154, NO. 4, DECEMBER 2010 Although the impact hazard is clearly a matter that affects all nations, to date only the United States government has taken steps to address the problem directly through scientific research and astronomical observations, as previously described. Further, all governments seem to share a reluctance to include impacts within their disaster planning and responsibility (Garshnek et al. 2000). When this issue does surface, it is likely to be discussed in terms of the smaller impacts. Although as individuals we are more at risk from large impacts with their global reach, a disaster manager or government official is more likely to be faced with a small impact within his or her jurisdiction. Eventually it will be necessary to decide who, or what agency, should be in charge of efforts to deal with the impact hazard, from possible extensions of the Spaceguard Survey to potential testing of defensive systems to preparing to deal with the aftermath of an impact. Within the United States, the president’s science adviser in 2010 officially nominated NASA to be the lead agency for searches, orbit determinations, and impact predictions. Other countries have not yet addressed this issue. Directory: files files -> Answer True False 2 points Question 2 files -> Integer programming and game theory files -> 4 Integer Programming files -> Bpa vehicle Window Repair Scenario #1 task: Procure vehicle window relacement. 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