Colloquia are normally on Tuesdays at 11:00 am in the 4th-floor conference
room, except as indicated below in **bold text**.

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*For questions or suggestions for speakers, please contact
the SwRI colloquium organizers:
Hannah Kaplan, 720-208-7208 or kaplan(at)boulder.swri.edu
Derek Lamb, 720-208-7207 or derek(at)boulder.swri.edu
Katie Primm, 720-240-0124 or kprimm(at)boulder.swri.edu
Raluca Rufu, 303-226-0879 or raluca(at)boulder.swri.edu
Julien Salmon, 720-208-7203 or julien(at)boulder.swri.edu
Kelsi Singer, 303-226-5910 or ksinger(at)boulder.swri.edu
*

*To be added to the SwRI Boulder Colloquia email list, please contact
Kelsi Singer, ksinger(at)boulder.swri.edu *

Tue Nov 19, 2019 | 11:00 am | Alex Davis | University of Colorado Boulder | Applications of the Full-Two Body Problem: Constraints on Formation and Parameter Estimation of Binary Asteroids | |

Abstract: | Traditionally the coupled dynamics of binary asteroids are modeled using the full-two body problem (F2BP). The F2BP represents each asteroid as an arbitrary mass distribution with a mutual gravity potential which imparts both accelerations and torques on the relative motion of the bodies. We apply the Hou inertia integral method of the F2BP to develop a high fidelity and computationally efficient tool for the study of binary asteroid dynamics. Within the framework of the F2BP two equilibria exist, an inner unstable equilibrium and an outer stable equilibrium. The inner unstable equilibrium acts as a boundary between collision and orbital separation and has been studied in a simplified planar formulation to understand binary formation by Jacobson and Scheeres. We build on this study, finding that the inclusion of nonplanar and higher order terms produces results consistent with their formation predictions, while placing further constraints on the cohesive strength for their proposed secondary fission process. In performing this analysis we also find that the effects of the higher order gravity terms tend to torque the geometry of the inner equilibrium away from principal axis alignment. This has implications for the mass distributions and geometries of contact binaries such as Itokawa and MU69. In studying the oscillations of binary dynamics near the outer stable equilibrium we identify fundamental frequencies of the system which are directly relatable to binary mass parameters. We can thus develop a sensitivity matrix which relates observations of the dynamics to values of the mass parameters assuming some idealized observer. Thus we are able to develop an estimation technique for the mass parameters of binaries near this commonly occurring equilibrium. We apply our analysis to the LUCY flyby target 617 Patroclus in order to place constraints on the observation quality necessary to measure the systems masses and moments of inertia. We find that such an approach is not feasible with ground observations, but a concerted campaign of observations by the spacecraft may be able to measure these mass parameters. | ||||

Tue Feb 25, 2020 | 11:00 am | Kathryn Steakley | NASA Ames | TBD Impacts | |

Tue Mar 3, 2020 | 11:00 am | Hakeem Oluseyi | NASA Headquarters | TBD Science Outreach | |

Tue Mar 31, 2020 | 11:00 am | Hannah Jang-Condel | University of Wyoming | TBD |