In the past 15 years, three previously unrecognized sub-populations of
near-Earth asteroids (NEAs) have been discovered. About 15% of NEAs
are binaries, at least 10% of NEAs are contact binaries, and dozens
of asteroid pairs have been identified. Numerous science questions
have arisen about the formation and evolution processes of these
systems and about the inter-relationships between these groups.
Addressing these questions informs us about a wide range of important
solar system processes that shape small bodies and planetesimals.
Here I have chosen to focus on providing one of the most complete
characterizations of a binary system among all known asteroid
binaries, and on studying the spin-orbit interactions in this and 8
additional binary systems. One hypothesis that has not been fully
explored is the possibility of chaotic rotation of asteroid satellites
and the impact that such a state has on the evolution of the binary
systems. I examine this problem as well as the possibility of
detecting librational motions in synchronous satellites. Because the
Arecibo and Goldstone radar systems enable superb characterizations of
binaries and NEAs in general, this dissertation makes abundant use of
radar data. Radar observations provide images of asteroids at
decameter resolution, and these images can be inverted to determine
the 3D shapes of the components, which are essential to properly model
the system dynamics. Radar data also enable precise determination of
the mutual orbit, which is another crucial ingredient. In the first
two chapters of the dissertation, I describe the observations and
physical characterizations of asteroid 2000~ET70 and binary asteroid
2000 DP107. The characterization of 2000 DP107 includes size, shape,
spin, mass, and density of each component, making this binary one of
the best-characterized asteroid binary to date. In the last chapter
of the dissertation, I describe a computationally efficient
fourth-order numerical integrator that I used to investigate the
coupled spin and orbital dynamics of the satellites of NEAs. The speed
of the integrator enabled multi-year timescale simulations of 9
well-characterized binary near-Earth asteroids. The numerical
simulations illuminate a range of rotational regimes for asteroid
satellites and the conditions under which the various regimes prevail.
One of the rotational regimes is chaotic, and I find that this
rotation state can substantially delay the radiative evolution of
binary systems.