Asteroid Affirmative



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Deflection – Propulsion



Electric propulsion technologies are on the way and will be able to deflect threatening asteroids

Walker in 8 (Dr. Roger Walker, Dr. Dario Izzo, Cristina de Negueruela, Dr. Leopold Summerer Advanced Concepts Team, European Space Agency, Dr. Massimiliano Vasile Dipartimento di Ingegneria Aerospaziale, Concepts For Near-Earth Asteroid Deflection Using Spacecraft With Advanced Nuclear And Solar Electric Propulsion Systems, http://www.esa.int/gsp/ACT/doc/PRO/ACT-RPR-PRO-2005-ConceptsForNear.pdf DF)

The study has assessed the maximum deflection capability achievable with spacecraft using highpower, high specific impulse electric propulsion and advanced power system technologies likely to be available within the next decade or so. Using the maximum current launcher lift capacity into low Earth orbit, a 15-20 ton-class spacecraft can perform rendezvous, spin axis re-orientation and deflection of a 10 megaton (approx. 200 m) Earth-impacting asteroid within a minimum response time of 10-20 years. Hence, it can be concluded that electric propulsion deflection is very effective for this class of asteroid, considering that typical warning times are of the order of 10-50 years. Larger asteroids of 300 m have a mass over three times larger and therefore it can be expected that response times would be in the 30-60 years range, which is still reasonable. It should be noted that these sizes of asteroids would represent the peak of the impact hazard once existing surveys have retired the risk from km-sized bodies with potential to cause global devastation.



Deflection – Asteroid Trapping



Bringing NEO’s into Earth’s orbit is an important first step in protection, reduction of costs and resource development of space.

Rather et al. 2010 [John; Powell, James Maise, George "New Technologies and Strategies to Exploit Near Earth Asteroids for Breakthrough Space Development."

AIP Conference Proceedings; 1/28/2010, Vol. 1208 Issue 1, p566-570, 5p, 3 Black and White Photographs, PN]

Abstract. The past two decades have brought a profound expansion of knowledge of near earth objects (NEO). If creatively exploited, NEOs can significantly increase human safety while reducing costs of exploration and development of the moon, Mars and the solar system. Synergistically, the ability to defend the Earth from devastating impacts will become very effective. A spherical volume having a radius equivalent to the moon’s orbit, 400,000 km, is visited every day by approximately ten NEOs having diameters of ~10 meters, while ~30 meter diameter encounters occur about once per month. Because these objects are usually very faint and only within detectable range for a few days, they require specialized equipment to discover them with high probability of detection and to enable accurate determination of orbital parameters. Survey systems are now being implemented that are cataloging many thousands of objects larger than 30 meters, but numerous advantages will result from extending the complete NEO census down to 10 meter diameters. The typical compositions of such NEOs will range from ~80% that are low density dust & rock “rubble piles” to perhaps 2% containing heavy metals – properties well known from meteorite samples. It is quite possible that there will also be some fragments of short period comets that are rich in water ice and other volatile components.
Small NEO’s can be positioned to deflect larger PHO’s that would otherwise cause apocalyptic scenarios if they collided with Earth.

Rather et al. 2010 [John; Powell, James Maise, George "New Technologies and Strategies to Exploit Near Earth Asteroids for Breakthrough Space Development."

AIP Conference Proceedings; 1/28/2010, Vol. 1208 Issue 1, p566-570, 5p, 3 Black and White Photographs, PN]



Fast repositioning of NEOs is necessary for certain missions. A large solar concentrator can be permanently attached to selected, captured, small asteroids for high-thrust generation. This capability is the key to a practical defense against in-coming high velocity Earth-threatening objects. “Well-behaved” NEOs will have velocities of a few kilometers per second relative to the Earth, while objects from the outer solar system can have velocities up to 70 km/sec. Since kinetic energy scales with the square of the velocity, the destructive potential of collisions with even small objects is tremendous. The relative velocity of 3.5 km/sec provides a convenient mnemonic: a collision of any mass at this relative velocity liberates the equivalent energy of the same mass of high explosive TNT. Thus 7 km/sec yields four times more energy, and 70 km/sec 400 times more. This leads to the ability to defend against fast incoming objects not by rendezvous with them but simply by placing small NEOs directly in their path.


Deflection – Asteroid Trapping



Using a solar concentrator, a NEO could be viably trapped for use at a low cost within a few years.

Rather et al. 2010 [John; Powell, James Maise, George "New Technologies and Strategies to Exploit Near Earth Asteroids for Breakthrough Space Development."

AIP Conference Proceedings; 1/28/2010, Vol. 1208 Issue 1, p566-570, 5p, 3 Black and White Photographs, PN]

Fast reaction times after discovery will enable reaching useful NEOs and capturing them or modifying their orbits for future use. One technological approach could utilize a very large, low weight solar concentrator to first power its associated plasma-propelled spacecraft to a fast rendezvous with the chosen NEO. The spacecraft would be equipped with small rocket-propelled 1000 kg probes that would be launched at high velocity into the approaching NEO to coarsely reduce its delta-v. The solar concentrator spacecraft would then rendezvous with the NEO and evaporate material from it to further decelerate and steer it precisely into a trapped orbit of the Earth. A separate prese/ntation at this meeting (Powell et al., 2010) provides details of a 100 meter diameter solar concentrator and its magnetically inflated cable (MIC) deployment system capable of providing ~10 megawatts of solar energy at the focus. The MIC concentrator can be packaged and deployed from a five cubic meter container weighing less than 20,000 kg that can be launched into space by Titan IV or Ares I-class rockets. It would be convenient to initially deploy and test the solar concentrator/rendezvous spacecraft in low orbit near the space station after which it would propel itself to high orbit to await NEO rendezvous opportunities. Incidentally, this would provide an important extended mission for the space station. When necessary, the concentrator spacecraft could return to low orbit for servicing and refueling. Compared with more traditional rocket alternatives for performing equivalent missions, the proposed system could be deployable at relatively low cost within a few years.
Capture of NEO’s in the Earth’s orbit shields us from radiation, allows for creation of habitats, collection of immense solar energy, and boost industrial growth on Earth through heavy metals.

Rather et al. 2010 [John; Powell, James Maise, George "New Technologies and Strategies to Exploit Near Earth Asteroids for Breakthrough Space Development."

AIP Conference Proceedings; 1/28/2010, Vol. 1208 Issue 1, p566-570, 5p, 3 Black and White Photographs, PN]

In this paper we will propose a set of new technologies and strategies for exploiting NEO resources that can yield important space development breakthroughs at much lower costs than existing concepts. Solar powered “Tugboats” deployed at the space station can rendezvous with carefully selected NEOs and steer them into captured orbits in the lunar L4 & L5 regions. Robotic equipment will then modify them for a plethora of benefits. Notably, the problem of radiation shielding against the Van Allen belts, solar flares and cosmic rays will be solved. Free transportation from low earth orbit to the moon and beyond will be feasible via shielded habitats in elliptical orbits. Large, comfortable habitats for long duration trips to Mars and beyond can be built. Propulsion for orbital transfer and maneuvering of heavy payloads can be accomplished by solar energized ejection of NEO materials. Industries can be developed based upon reconditioning materials for use in space and recovery of heavy metals for use on Earth.

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