mountain profile Institute for Astronomy University of Hawaii


Ast 622: The Interstellar Medium
Spring 2016 Mondays, Wednesdays 2-3:20pm
Jonathan Williams, Institute for Astronomy


The Interstellar Medium (ISM) is the gas and dust between the stars. Stars form from it, their winds and supernova enrich and replenish it. Temperatures in the ISM range from the very hot, >106K, to the very cold, <10K. Observed densities span an even wider dynamic range, from <10-3 to >106 particles per cubic centimeter. Even the highest densities, however, are more rarefied than the best vacuums currently attainable on Earth and thus the ISM allows us to explore physical processes in unique environments. This course will cover observations and theories of a wide range of ISM environments from pervasive diffuse, ionized gas to dense, star forming cores in molecular clouds.

Although this is a major area of research in general, there is relatively little direct work within the IfA. However, many of the physical processes that I will lecture on have applications in varied areas from planetary atmospheres to galaxy formation. The structure of the class is designed to emphasize utility by alternating between lectures and student-led discussions on problem sets and topics of current research. Participation and performance in the homeworks and discussions account for 60% of the course grade.

I will give handouts for each lecture and pointers to additional reading. There is no official course book but I frequently refer to the following:

The second main part of the course will be an independent research project chosen from the list below. These require analzying (reduced) datasets and/or independently verifying calculations and results. Most are based on published work and the goal is for each student to go through the analysis steps themselves and to see how the concepts introduced in the lectures are applied in research. The student should produce a 4-page paper in the style of an ApJ Letter 2 weeks before the end of the semester and present their work in pecha-kucha format (20 slides x 20 seconds). The paper and presentation will together account for the remaining 40% of the course grade.