How do objects orbit if more than 2 massive bodies are involved?
Newton's versions of Keplers 3 Laws of Planetary Motion are only
strictly valid for 2 massive bodies. The Solar System, however, clearly
has more than 2 massive objects within it. How do we handle this
many-body problem? This lecture discusses some of the multi-body
gravitational effects seen in our Solar System (and by extension
elsewhere). We will describe Lagrange Points for the restricted 3-body
problem and consequences like the Trojan Asteroids of Jupiter,
long-range gravitational perturbations and their aid in discovering the
planet Neptune, close encounters that can dramatically alter the orbits
of comets and give us ways to slingshot spacecraft into the outer and
inner Solar System without huge expenditures of fuel, and orbital
resonances that can amplify small long-range perturbations and either
stabilize or destabilize orbits. All of these effects play a role in
the Dynamical Evolution of our Solar System that we will see throughout
later parts of the course. Recorded 2007 Oct 18 in 1000 McPherson Lab on the
Columbus campus of The Ohio State University.