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- They work for big asteroids and can be deployed in a short timeframe
- Kinetic impactor solves
- Hitting an asteroid idea
Solvency – Kinetic ImpactorsKinetic impactor solvesKoenig & Chyba ‘7 (Jesse D. and Christopher F., SpaceDev Inc and Department of Astrophysical Sciences and Program on Science and Global Security, Woodrow Wilson School of Public and International Affairs, Impact Deflection of Potentially Hazardous Asteroids Using Current Launch Vehicles, http://www.aero.org/conferences/planetarydefense/2007papers/S2-3--Koenig-Paper.pdf) Nuclear explosions, and a wide variety of technologies not yet realized, have been proposed to deflect asteroids away from collision with Earth. In contrast, here we present realistic models for simple kinetic energy impact deflection, using the actual orbital elements of 795 catalogued Potentially Hazardous Asteroids, and impactor masses launched to intercept trajectories by Atlas V HLV rockets or equivalent. We take asteroid diameter, density, cratering characteristics, and Earth-collision lead time as parameters whose influence is to be investigated. Assuming asteroids of rock-like density, we find deflection off of Earth-collision to be achievable given 5- year lead time with a single kinetic energy intercept for 100% of 250 m diameter PHAs, 20-year lead with a single intercept for 93% of 500 m PHAs, 20-year lead with five and ten intercepts respectively for 55% and 94% of 1 km PHAs, or 100- year lead with one and two intercepts respectively for 55% and 94% of 1 km PHAs. Considering likely future lead times for Near-Earth Objects, simple impact deflection using current launch vehicles is therefore a viable strategy for up to kilometer-diameter asteroids. This method has important advantages over other proposals: it requires no new technologies, would not require development or testing of nuclear warheads, and would likely be the least costly, least risky, and fastest to effect. They work for big asteroids and can be deployed in a short timeframeKoenig and Chyba, 07 < Jesse D. and Christopher F., SpaceDev Inc and Department of Astrophysical Sciences and Program on Science and Global Security, Woodrow Wilson School of Public and International Affairs, Impact Deflection of Potentially Hazardous Asteroids Using Current Launch Vehicles, http://www.aero.org/conferences/planetarydefense/2007papers/S2-3--Koenig-Paper.pdf> Assuming lead time of two decades, simple impact is an effective deflection method with few launches (1 to 3) for PHAs up to 500 m, either with rock-like density (3 g/cm3) and significant cratering ejecta, or with low density (0.5 g/cm3) and no ejecta— encompassing the majority of potential threats. It is important to note that we make no assumptions of extraordinary amounts of ejecta. In fact, our cratering model gives ejecta momentum ratios far lower than some others found in the literature (e.g. the ratios shown in Figure 2D, typically in the range 8 to 10, vs. the ratio of 38.5 in the model due to Holsapple20). Different asteroids have different physical properties, so will have different cratering behavior; porous and incoherent asteroids may give very little ejecta, and therefore we also simulated impacts with zero ejecta to provide a worst case extreme in this regard. Assuming lead time of a century and few launches, impact deflection is effective with significant cratering for the vast majority of rock-like PHAs up to 1 km, and without ejecta for 400 m rock-like PHAs or 750 m low-density PHAs. Furthermore, because of its simplicity, technological readiness, and low risk level, kinetic energy impact may still be the preferred option in the case that more numerous launches are required, for especially large asteroids or short warning times. With 20-year lead, five and ten intercepts will successfully deflect 55% and 94%, respectively, of 1 km rock-like PHAs. Kinetic impactor solvesValsecchi ‘7 (G.B., INAF-IASF & A. Milani Comparetti, Department of Mathematics, University of Pisa, Ch. 11: Evaluating the Risk of Impacts and the Efficiency of Risk Reduction, in Comet/Asteroid Impacts and Human Society: An Interdisciplinary Approach, SpringLink) A quantitative analysis of the problem shows that, if the two conditions just mentioned are met, then a relatively small mass spacecraft (about 500 kg), impacting at a speed of the order of 10 kms–1, could transfer enough linear momentum to deflect a NEA of 300–500 m diameter away from its Earth-colliding orbit. In fact, the largest unknown in this scenario is the amount of linear momentum transferred, that depends not only on the mass and speed of the impacting spacecraft, but also on the detailed physics of the formation of a crater on the NEA, with the ensuing ejection of material in the direction opposite to that from which the spacecraft arrives. They work for big asteroids and can be deployed in a short timeframeKoenig and Chyba, 07 < Jesse D. and Christopher F., SpaceDev Inc and Department of Astrophysical Sciences and Program on Science and Global Security, Woodrow Wilson School of Public and International Affairs, Impact Deflection of Potentially Hazardous Asteroids Using Current Launch Vehicles, http://www.aero.org/conferences/planetarydefense/2007papers/S2-3--Koenig-Paper.pdf> Assuming lead time of two decades, simple impact is an effective deflection method with few launches (1 to 3) for PHAs up to 500 m, either with rock-like density (3 g/cm3) and significant cratering ejecta, or with low density (0.5 g/cm3) and no ejecta— encompassing the majority of potential threats. It is important to note that we make no assumptions of extraordinary amounts of ejecta. In fact, our cratering model gives ejecta momentum ratios far lower than some others found in the literature (e.g. the ratios shown in Figure 2D, typically in the range 8 to 10, vs. the ratio of 38.5 in the model due to Holsapple20). Different asteroids have different physical properties, so will have different cratering behavior; porous and incoherent asteroids may give very little ejecta, and therefore we also simulated impacts with zero ejecta to provide a worst case extreme in this regard. Assuming lead time of a century and few launches, impact deflection is effective with significant cratering for the vast majority of rock-like PHAs up to 1 km, and without ejecta for 400 m rock-like PHAs or 750 m low-density PHAs. Furthermore, because of its simplicity, technological readiness, and low risk level, kinetic energy impact may still be the preferred option in the case that more numerous launches are required, for especially large asteroids or short warning times. With 20-year lead, five and ten intercepts will successfully deflect 55% and 94%, respectively, of 1 km rock-like PHAs. Hitting an asteroid ideaLamb Nodate, (Robert Lamb is a senior fellow and deputy director of the Program on Crisis, Conflict, and Cooperation (C3) at CSIS, researching governance and development amid conflict, Howstuffworks.com, “TOP 10 WAYS TO STOP AN ASTEROID”, http://dsc.discovery.com/space/top-10/asteroid-stopping-technology/index-03.html, SH) Some scientists think the whole "nuke the asteroid" strategy is overreacting. Why not give it a kinetic love tap? Enter NASA's alternative "kinetic interceptor," which would deflect an incoming asteroid by smacking into it. Like shooting a rolling bowling ball with a pellet gun, the idea is to just barely nudge the asteroid off course -- but not hard enough to fracture it. According to Space.com, a mere 1 mile-per-hour (1.6 kilometer-per-hour) impact would be enough to divert an asteroid by 170,000 miles (273,500 kilometers) if we hit it 20 years before the predicted collision. 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. Objective files -> Pop Warner History files -> North Carolina Inclusion Initiative Mapping Where Children with ieps are Being Served Purpose files -> Fall 2013 Spring 2014 Program Data: Standard 1 Exhibit 4d files -> Hanban – asia society confucius classrooms network 2010 request for proposal files -> Northern England’s set-jetting locations Download 1.03 Mb. Share with your friends:
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