# ASTR450

Orbital
Dynamics, Fall 2017

## ASTR450 Course Description

The solar system is a very dynamic place. The planets orbit the Sun
along elliptical orbits but, on longer timescales, their orbits
oscillate and precess -- some chaotically -- due to mutual
gravitational perturbations. Asteroids are perturbed by resonant
forces onto orbits which cross the Earth's orbit; occasionally these
objects strike our planet with deadly consequences. Jupiter tosses
some comets into the Sun and ejects others from the solar system.
Planets can also capture comets as temporary moons; some escape again
while others are less lucky (like Shoemaker-Levy 9 which crashed into
Jupiter in 1994). Ocean tides raised by the Moon are increasing the
Earth-Moon distance by 3.7cm/year, thereby causing the length of our
day to slowly increase. The same effect has driven the moons of
Jupiter into resonance with one another, generating enough heat to
power Io's volcanos. In Orbital Dynamics (ASTR450), we
will study these and other important orbital phenomena. The course
will emphasize analytical calculations, numerical simulations, and
computer programming techniques. The prerequisites for ASTR450 are:
(ASTR121 or ASTR 200) and (PHYS 273 or PHY 263).
## Some Topics that we will cover in this class:

- Gravitational and Non-Gravitational Forces
- Two-body Problem (Energy + Angular Momentum)
- Three-body Problem (Roche Lobes, Zero Velocity Curves)
- Many-body Problem
- Orbital Elements + Orbital Perturbation Theory
- Tidal Forces and the Evolution of the Moon's orbit
- Orbital Resonances and the ``Capture'' of Pluto
- Resonant Sculpting of the Asteroid Belt
- Future of the Solar System - Chaos!

## Web Site:

http://www.astro.umd.edu/~hamilton/ASTR450/

## Grading Policy:

The grading for the class will be according to the following table.

Assignment |
ASTR450 |

Homework |
275 |

Mini-Midterms |
50 |

Midterm |
100 |

Final |
250 |

Participation |
75 |

Total |
750 |

Return
to ASTR450 Home Page