This course provides an intensive introduction to galaxies and cosmology. Among covered topics are the life and death of stars; properties and evolution of galaxies; the matter content, geometry, history and future of the universe; and exotic phenomena like supermassive black holes and gamma-ray explosions. Many of the topics covered in ASTR220 are also covered in ASTR110 but with more depth and mathematical complexity. ASTR210 and ASTR220 together provide an in depth introduction to all fields of astronomy.
Pace Of Quantitative Training:
The course emphasizes the connections between real-world objects such as stars and galaxies, the laws of physics that describe their workings, and the mathematics which in the end provides the answers. The most important aspect is identifying the physical relations that are needed to describe the problem in mathematical terms. This skill will be developed through practice (problem sets) and explanations and discussions in the classroom.
Expected Quantitative Preparation:
Students who attend ASTR220 are not expected to have any knowledge of astronomy, but they are expected to have a strong background in high-school math and physics. The course makes use of algebra and geometry; no calculus is used. Mathematical techniques will be (quickly) reviewed, mostly at the start of the course, for those who have the required background but do not have much recent experience. If you are uncertain about whether you are ready for this course, please talk with the instructor.
Sample Problem:
The problems will typically NOT be phrased as an equation: most of the credit will usually be earned by finding the right equation!
Example of a “math-heavy” homework problem:
Galaxies are nearly empty. Demonstrate this by calculating the probability that you would hit a star if you travelled on a straight line through the center of a galaxy. Assume that the galaxy is a sphere with a radius of 100,000 light years, and that it contains 200 billion stars. Also assume that all the stars in the galaxy are uniformly distributed and have the same radius as the Sun. Use the facts that one solar radius = 6.96x1010 cm and one light-year = 9.47x1017 cm.