The effects of the collision of a Near-Earth-Object(NEO) with the Earth could be catastrophic on a local, regional or global scale depending on the size of the NEO. Therefore, there is considerable interest in determining ways to mitigate the threat posed by these objects. This dissertation presents a method utilizing a tethered ballast mass for altering the trajectory of a NEO with an Earth-intersecting orbit so that it avoids hitting the Earth. The method is simulated using four different methods. The first method assumes a rigid massless tether. Using this method, a parametric study was conducted to determine the effectiveness of the technique over a wide parametric space. Specifically, this study provided results in terms of deviation rates over the parametric space. After this, the massless inelastic method was used to study actual miss distances assuming the asteroid was on a collision course with the Earth. After this, a study was conducted, using the massless, inelastic model, in which the mass of the ballast was made constant, in order to determine the minimum tether length required to divert asteroids simulated based on actual asteroids from NASA's potentially hazardous asteroid (PHA) database, again assuming a massless inelastic tether. Finally, it was desired to determine how relaxing the constraints of the massless inelastic model would affect system performance. Therefore, three more models were introduced: massive inelastic, massless elastic, and massive elastic. Using these models, a study was performed to explore the effects of the changed model on system performance and to compare the results in terms of deviation, with those of the massless inelastic model. This was desired because the numerical cost of the new models was much higher than that of the massless inelastic model, so rather than conduct the study over a much larger parametric space, a smaller space was chosen, so that the results could be compared.
| Identifer | oai:union.ndltd.org:NCSU/oai:NCSU:etd-07152009-152128 |
| Date | 28 July 2009 |
| Creators | French, David Bruce |
| Contributors | Andrew P. Mazzoleni |
| Publisher | NCSU |
| Source Sets | North Carolina State University |
| Language | English |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://www.lib.ncsu.edu/theses/available/etd-07152009-152128/ |
| Rights | unrestricted, I hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dis sertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to NC State University or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report. |
Page generated in 0.0023 seconds