No nasa space launches now- partisan fighting and controversies prevent all funding Handberg 7-25
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AT: Space TetherNo solvency- Space Tether technology wont exist for years Kaplan 09 (Ph.D. Johns Hopkins University/Applied Physics Laboratory, Chief Engineer on Two Launch Vehicale Programs, Advanced Degree of Aeronautics and Astronautics from MIT and Stanford, Fellow of the American Institute of Aeronautics and Astronautics, Fellow of American Astronautical Society) Marshall H., Kaplan September 14-17, 2009, Survey of Space Debris Reduction Methods”, AIAA SPACE 2009 Conference & Exposition The underlying principle of the electrodynamic tether is the utilization of electromagnetic forces generated by a current passing through a long conductor in the earth’s magnetic field. If currents are properly directed and timed, a net force can be generated that causes an orbit to change. According to electromagnetic theory, such a force is possible only in the presence of open-loop electric current flow. The space environment seems to offer the possibility. If tether researchers are correct, electrical current can flow along a tether and depart into the ambient plasma around the conductor. This has led to the conclusion that the Lorentz force acts only on the tether, creating a net force that may be used to make orbit adjustments.12 Although no physical principles appear to be violated, the use of tethers for debris reduction does introduce a number of engineering challenges. The Earth’s magnetic field is essential to the electrodynamic tether concept, because it is the interaction of this field with the electrical current in tethers that creates net forces used to maneuver tether devices. The magnetic field varies in direction and magnitude with orbital position. Thus, a tether must continually adjust its orientation and the direction and level of current flow in order to carry out effective orbit changes. Since the tether must be stabilized and structurally stiff, it must be spinning. However, this further complicates operational aspects of debris collection. Nevertheless, the concept does seem to have some promise for debris removal applications. For example, there have been claims that such tethers can achieve velocity changes in excess of 50 km/sec/year for many years, without using propellant.13] International CP HelperThe US should pursue negotiations on space debris Denmark et. Al 10 (Abraham M. Denmark, Dr. James Mulvenon, Frank Hoffman, Lt Col Kelly Martin (USAF), Oliver Fritz, Eric Sterner, Dr. Greg Rattray, Chris Evans, Jason Healey, Robert D. Kaplan, “”Contested Commons: The Future of American Power in a Multipolar World,” January 2010, http://www.cnas.org/files/documents/publications/CNAS%20Contested%20Commons_1.pdf) The United States should consider diplomatic initiatives in two similar areas with an eye toward making it more difficult to develop counter-space capabilities. The growth of space debris and the threat it presents to all spacecraft has risen in importance on the international agenda. In 1980, only 10 countries operated spacecraft and the Air Force tracked 4,700 objects in space. By 2009, over 50 actors owned or operated spacecraft and the U.S. Space Surveillance Network was tracking about 19,000 objects in orbit, straining resources and creating problems for space operations. 66 Trends indicate that problems will continue to grow. 67 Concerns about debris led NASA to adopt and promulgate standards for debris creation in 1995. Other U.S. agencies adopted those standards in 2001, and the major space-faring countries followed suit in 2002. 68 U.S. leadership in this area heightened international interest and concern about debris, widening interest in the global consequences of China’s 2007 ASAT test and contributing to the number of actors willing to condemn it. Debris agreements are voluntary and largely unenforceable. Still, debris represents a classic “tragedy of the commons” problem in which strong leader-ship can make a difference. Nearly a half century ago, American economist Mancur Olson argued that small groups could cooperate to provide public goods when each member of the group benefited from doing so, even if the group was not comprehensive. 69 Fortunately, the number of countries launching spacecraft is considerably smaller than the number of countries that own them. The dominant space launch entities include the United States, Russia, China, ESA, Japan, and India. Israel and Iran have also conducted space launches, and North Korea has attempted them. By themselves, the six dominant space-launching countries could share information to reduce debris created by their launch vehicles and seek agreement to require that payload providers demonstrate that they meet certain debris standards before being accepted for launch. Doing so would emphasize the importance of debris mitigation — an area in which the United States leads — and, possibly, increase the diplomatic penalties for testing kinetic anti-satellite systems. To the degree such a regime were honored, it would improve the long-term operational environment for all space actors, whether civil, military, or commercial. There are additional areas in which more technically-focused rule-making might contribute to a stable regime that supports space commerce and advances U.S. interests. These areas include liability for accidents, PNT coordination (given the continuing proliferation of such systems), scientific data standards (particularly in the area of Earth observation), information-sharing associated with space situational awareness, and proximity operations around foreign spacecraft. The seeds for these activities have already been planted. |