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Showing 1 to 20 of 138 for “"Asteroid"”.
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Multiple Asteroid Retrieval Mission
… of spacecraft capable of reaching Near-Earth asteroids. To analyze this idea, the goal of this problem is to maximize the asteroid mass retrieved within a spacecraft max life span. Explicitly, the maximum lifetime of the spacecraft fleet is set at 30 years. A fuel supply-chain is proposed and …
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ROAD : Rapid Optical Asteroid Detection
… problem, which seeks to identify near-Earth asteroids of arbitrary position and velocity using ground-based optical systems. In the process of establishing the optimality of these algorithms, we formalize the blind search streak detection problem and survey several other state of the art …
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Trojan asteroid spectroscopy and space weathering
Trojan asteroids orbit the Sun at Jupiter's L4 and L5 stability points. They are included in the D-class group of asteroids because of their characteristically steep spectral slope. In accordance with spectra of other asteroid classes, we expected that the larger the diameter is of a D-class …
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Preliminary Design of an Asteroid Hopping Mission
… of a mission to visit a number of near Earth asteroids (NEAs). The mission would take place before the end of the 21st century, and would only use commercially available technology. Throughout the mission design process, while holding astronaut safety paramount, it was the goal to maximize the …
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Satellite Deceleration Using Gravity Assist from Asteroid
… satellites. This has been theorized to slow down asteroids using the moon to capture them in earth’s orbit. My goal is to determine if asteroids can be used to provide a change in speed great enough to the point that after multiple of these maneuvers the satellite can come to a stop. By being able …
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Tracing meteorite source regions through asteroid spectroscopy
… Model (MGM) as a mathematical tool, we treat asteroid and meteorite spectra identically in the calculation of 1-micron and 2-micron geometric band centers and their band area ratios (BARs). Using these identical numerical parameters we quantitatively compare the spectral properties of S-, Sq-, …
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Forging asteroid-meteorite relationships through reflectance spectroscopy
… were obtained for 196 main-belt and near-Earth asteroids to determine plausible meteorite parent bodies. These spectra, when coupled with previously obtained visible data, allow for a better determination of asteroid mineralogies. Over half of the observed objects have estimated diameters less …
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Asteroid deflection campaign design integrating epistemic uncertainty
Planetary defense, or asteroid collision avoidance, has been gaining interest with recent meteor or fly-by events, including the Chelyabinsk meteor that entered the Earth's atmosphere and exploded over Russia in 2013. Past or planned robotic missions to near-Earth asteroids are expected to provide …
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Asteroid hazard mitigation: deflection models and mission analysis
… and evolution of the solar system. Among all asteroids, NEOs have stepped into prominence because of two important aspects: they are among the easiest celestial bodies to reach from Earth, in some cases with less demanding trajectories than a simple Earth-Moon trajectory and, even more …
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An observational investigation of the comet-asteroid connection
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1990.
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Translational and Rotational Control of an Asteroid Orbiting Satellite
… is to analyze an effective control scheme for an asteroid orbiting satellite. The thesis first summarizes the progress made in the dynamics formulation of such satellites and then provides a theoretical framework for the control system design. The control objective is to maintain a nadir pointing …
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Mass wasting and the Coriolis effect on asteroid Vesta
… motion related to the Rheasilvia impact basin on asteroid (4) Vesta's southern hemisphere. The giant basin is 500km in diameter, with a centre which nearly coincides with the rotation axis of Vesta. The Rheasilvia basin partially overlaps an earlier, similarly large impact basin, Veneneia. Mass …
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Optimal strategies for selecting from multiple asteroid interception targets
… to space systems. The concept is applied to an asteroid interception problem using low-thrust propulsion and solved through a combination of particle swarm optimization (PSO) and a commercial non-linear programming (NLP) solver SNOPT (Sparse Nonlinear OPTimizer). The problem considers an …
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Rotationally resolved visible spectroscopy of the Asteroid 1 Ceres
… wavelength range of 6000 and 7000 Angstroms. The asteroid was observed for 6 nights, for lengths of time varying from 3 to 7.5 hours. The main goal was to support/refute the previous findings about absorption features within the wavelength range being observed. Additionally, this thesis was …
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Comet-asteroid differentiation using visible and near-infrared spectroscopy
… the properties that differentiate comets and asteroids. In this study, a number of cometary candidates were observed in visible and infrared wavelengths in an attempt to correctly classify them as asteroids or dormant or extinct comets. From this data, two groups of objects were identified: …
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Rotational lightcurve analysis of binary Asteroid (22) Kalliope/Linus
Binary asteroids have been insightful to scientists in recent years in their quest to better understand the Solar System in its early stage. Observing a mutual event between a primary and its moon can yield the sizes of the objects in units of the semi-major axis a. When the linear dimensions of …
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Spectral Study of Asteroids and Laboratory Simulation of Asteroid Organics
We investigate the spectra of asteroids at near- and mid-infrared wavelengths. In 2010 and 2011 we reported the detection of 3 ?m and 3.2-3.6 ?m signatures on (24) Themis and (65) Cybele indicative of water-ice and complex organics [1] [2] [3]. We further probed other primitive asteroids in the …
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Asteroid deflection and active debris removal methods with spaceborne lasers
… years to mitigate the risk of impact between an asteroid and the Earth. Most of the strategies proposed fall into two categories: impulsive and slow-push. Impulsive strategies are usually modelled with an instantaneous change of momentum given by, for example, a nuclear explosion (nuclear …
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Micrometeoroid Fluence Variation in Critical Orbits Due to Asteroid Disruption
<p>Micrometeoroids and orbital debris (MMOD) is a growing issue with international importance. Micrometeoroids are naturally occurring fragments of rock and dusk that exist throughout the solar system. Orbital debris is human made material like rocket bodies, paint flakes, and the effluent of …
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