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- Space tug solves Apophis
- Nuclear Weapons NW Now
- NASA currently plans to fire nuclear missiles at threatening asteroids
- NASA plans to fire nuclear missles at an asteroid in order to nudge it off course.
- NASA’s current plan to deal with Near Earth Objects is to explode it with nuclear weapons
- The only way to deal with asteroids with our current technology is to push them out of orbit with nuclear weapons
- NASA currently plans to use an Ares V rocket to launch nuclear weapons at a threatening asteroid
Apophis – Gravity TractorGravity tractor can solve ApophisNASA ‘6 (“2006 Near-Earth Object Survey and Deflection Study” http://www.b612foundation.org/papers/NASA-finalrpt.pdf) The gravity tractor has been suggested to deliver the small momentum changes required for the keyhole deflection of Apophis. For this concept, the most mass at the PHO provides the most momentum change; therefore, an ion engine would be used to propel the vehicle. To provide enough thrust to reach the asteroid in a short period of time and rendezvous with the asteroid, eight NEXIS thrusters, similar to those used on the Jupiter Icy Moons Orbiter (JIMO), is used as the tractor’s propulsion system. The propellant mass used for transit, rendezvous, and hovering would be roughly 5000 kg, allowing for a mass of 20,000 kg to produce the gravitational force on the asteroid. Different deflection opportunities would change the available lead-time for the gravity tractor. Assuming a few years transit time for the low-thrust system, the gravity tractor may need to be launched in advance of the 2021 observation opportunity. Here, a 3-year transit time and a 6-year action time are assumed. If a mass of 20,000 kg were applied for 6 years against Apophis, it would impart a change in momentum of 4.8 x 107 kg m/s. This would change the asteroid velocity by 1 mm/s (0.001 m/s), insufficient to meet the 2019 opportunity (Design Point 1), but sufficient to avoid the keyhole, assuming improved tracking accuracy for the 2023 opportunity (Design Point 2). To achieve a change of one Earth radius in the short time span, the tractor’s mass would need to be about 150,000 kg. Apophis – Space TugSpace tug solves ApophisNASA ‘6 (“2006 Near-Earth Object Survey and Deflection Study” http://www.b612foundation.org/papers/NASA-finalrpt.pdf) The space tug is another slow push technique, and its use assumes that Apophis is structurally able to support attachment. The vehicle’s design could be similar to JIMO’s. The JIMO vehicle used eight NEXIS ion thrusters to propel an 18,000-kg spacecraft. If a Delta IV Heavy were used to launch the spacecraft, only 7,000 kg of fuel would be required, with 4,000 kg required for the 3-year transit period and rendezvous/docking, leaving 3,000 kg of fuel to produce a change in Apophis’s momentum. If the thrusters perform at full power, the active push time will be approximately 2.25 years, producing a change in momentum of 2.3 x 108 kg m/s. It is estimated that this would be sufficient for both the 2019 and the 2023 opportunities. A factor-of-eight increase in the mass of the PHO would increase the push time for the tractor by more than 14 years, exceeding the time available for this design. Building a system that is somewhat larger than JIMO using on-orbit assembly techniques could possibly solve the problem. Although relatively little momentum change is required to prevent Apophis from passing through the keyhole, many of the deflection techniques are simply too massive for current lift capabilities for the first design point. If the extremely limited requirements of Design Point 2 are considered, all concepts could hypothetically deflect the threat. A mission to prevent Apophis from passing through the 2026 keyhole appears to be possible with current technologies. Nuclear WeaponsNW NowNASA is committing the US into a nuclear-only deflection system that’s doomed to failChapman ‘6 Furthermore, the Report takes a totally backwards approach to characterization, saying that we first need to determine what deflection system we will use before addressing what characterization option we will try to build and implement. The "logic" is not what it should be, namely that we will select (from a tool-kit of relevant technologies) what deflection approach would be appropriate for an *identified* threatening NEO of a particular size; rather, it says (specifically in the last paragraph of pg. 73) that we will soon select a one-approach-fits-all deflection system (e.g. stand-off nuclear) as the preferred generic deflection scheme and only then design a characterization effort that will address the needs of that sole deflection approach. (The seriousness of this error is illustrated by the fact that the Report seems to select stand-off nuclear as the preferred approach -- because it is "most effective" -- and then ridiculously concludes that we need to know *less* about the physical nature of the NEO for stand-off nuclear than for all other deflection options! [This absurd argument is "developed" in the middle paragraph of pg. 61.].) NASA currently plans to fire nuclear missiles at threatening asteroidsO'Neill 2008 (IAN O'NEIL, O’Neill is a British solar physics doctor with nearly a decade of physics study and research experience, JULY 27, 2008, “ Bad Idea: Blowing Up Asteroids with Nuclear Missiles”, Universe Today, Accessed 6/21/11, http://www.universetoday.com/16066/bad-idea-blowing-up-asteroids-with-nuclear-missiles/, JK) The first thing that comes to mind when someone asks: "How do we deflect a near Earth asteroid?" is "Fire some nuclear missiles at it." However, this might not be the best course of action. Akin to opening a walnut with a sledgehammer, there might be a better, less messy option. This is what Apollo astronaut Rusty Schweickart thinks at least. Last year, NASA issued a report suggesting they were seriously considering a nuclear option should an asteroid threaten Earth. However, the ex-lunar module pilot believes this decision was manipulated by political pressure, possibly indicating the asteroid threat was being used to speed up nuclear proliferation in space… NASA plans to fire nuclear missles at an asteroid in order to nudge it off course.Cosmic Log 2007 (Cosmic Logic, March 21, 2007, Dueling over asteroids, Cosmic Log, accessed 6/23/11, http://cosmiclog.msnbc.msn.com/_news/2007/03/21/4350661-dueling-over-asteroids, JK) Those plans came out this month in the form of a report to Congress, laying out an analysis of the various methods for detecting and dealing with potentially hazardous asteroids and comets. It's all part of NASA's legislative mandate to find 90 percent of such near-Earth objects, or NEOs, wider than 460 feet (140 meters) by the year 2020. An asteroid that big could devastate a city-sized region if it were to hit Earth. Schweickart, who flew on Apollo 9 in 1969, set up the B612 Foundation to raise awareness about NEO threats - and he's organizing a series of workshops under the aegis of the Association of Space Explorers to develop an international plan for dealing with them. "Not to make it sound overly dramatic, but you're not dealing with just science, you're dealing with public safety issues," he told me today. "You're dealing with the survival of life." That's why he's taking the new report so seriously. NASA's official view is that the most efficient way to divert a potentially threatening NEO is by setting off a nuclear bomb nearby, to nudge it into a safe orbit. "The implication is that it is the preferred way to go to deflect essentially any near-Earth object," Schweickart complained. In contrast, Schweickart argues that the so-called "nuclear standoff" option should be used only as a last resort. He contends that 98 percent of the potential threats can be mitigated by using less extreme measures. For example, he favors the development of a "gravity tractor" - a spacecraft that would hover near an asteroid for years at a time, using subtle gravitational attraction to draw the space rock out of a worrisome path. NASA’s current plan to deal with Near Earth Objects is to explode it with nuclear weaponsGraham and Schweickart 2008 (Thomas Graham Jr. and Russell L. Schweickart, Ambassador Thomas Graham Jr. is a former senior-level diplomat and a world-renowned authority on nuclear nonproliferation, Russell L. Schweickart is a former Apollo astronaut and chairman of the B612 Foundation, February 18, 2008, “NASA's Flimsy Argument for Nuclear Weapons”, Scientific American, accessed 6/21/11, http://www.scientificamerican.com/article.cfm?id=nasas-flimsy-argument-for-nuclear-weapons, JK) Recently, however, a counterargument has been advanced—by NASA. In 2005 Congress ordered the space agency to analyze the alternatives that it could employ to divert a near-Earth object (NEO)—an asteroid or comet—if one was found to be on a collision course with our planet. Last March, NASA submitted a report entitled “Near-Earth Object Survey and Deflection Analysis of Alternatives,” having first coordinated its response with the White House, the Department of Defense and the Department of Energy. In its report NASA chose to analyze only the highly improbable threat posed by large NEOs, which very rarely strike Earth, in lieu of the more realistic danger of a collision with one of the cohort of smaller NEOs, which are far more numerous. What is more, the report emphasized the effectiveness of nuclear explosions in providing the force to deflect an NEO from a collision course, but it completely neglected the need for precision in such a procedure. The only way to deal with asteroids with our current technology is to push them out of orbit with nuclear weaponsHSNW 2010 (Homeland Security News Wire (HSNW), 30 June 2010, “ Scientist says nuclear weapons best bet for saving Earth from asteroids”, HSNW, Accessed 6/21/11, http://www.homelandsecuritynewswire.com/scientist-says-nuclear-weapons-best-bet-saving-earth-asteroids, JK) In the current state of human technology, the NRC warns, the only way to be sure is to use nuclear weapons to push these threat out of orbit: “Nuclear explosions are the only current, practical means for dealing with large NEOs (diameters greater than 1 kilometer) or as a backup for smaller ones if other methods were to fail.” Page notes that if this is indeed the case, then the current plans by President Obama to strive for “a world free of nuclear weapons” would have to be modified to allow for a few nuclear weapons to remain available for planetary defense. NASA currently plans to use an Ares V rocket to launch nuclear weapons at a threatening asteroidWagenseil 2007 (Paul Wagenseil, Paul Wagenseil is the managing editor of SecurityNewsDaily, August 08, 2007, “ NASA Researchers Ponder Nuclear Asteroid Deflector”, foxnews,com, accessed 6/22/11, http://www.foxnews.com/story/0,2933,292464,00.html, JK) NASA scientists have proposed a spacecraft that would use atomic blasts to deflect asteroids on collision courses with Earth. Researchers from the Advanced Concepts Office at NASA's Marshall Space Flight Center in Huntsville, Ala., presented the idea at the 2007 Planetary Defense Conference, held in early March in Washington, D.C. • Click here to view the slides from the presentation (PDF format). The asteroid deflector would be launched from low Earth orbit by an Ares V rocket, NASA's next-generation heavy-cargo lifter, scheduled to go into service in 2020 As it approached the asteroid, the craft would at one-hour intervals release six missile-like interceptors, each tipped with a B83 one-megaton nuclear warhead. The warheads would detonate one by one near the surface of the asteroid, pushing it far enough off course so that it passes comfortably wide of Earth. 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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