Month: January 2007

5 – Planetary Transits

5 – Planetary Transits

Professor Bailyn talks about student responses for a paper assignment on the controversy over Pluto. The central question is whether the popular debate is indeed a “scientific controversy.” A number of scientific “fables” are discussed and a moral is associated with each: the demotion of Pluto (moral: science can be affected by culture); the discovery of 51 Peg b (morals: expect the unexpected, and look at your data); the disproof of pulsation as explanation for the Velocity Curves (moral: sometimes science works like science).

4 – Discovering Exoplanets: Hot Jupiters

4 – Discovering Exoplanets: Hot Jupiters

The formation of planets is discussed with a special emphasis on the bodies in the Solar System. Planetary differences between the celestial bodies in the Inner and Outer Solar System are observed. Professor Bailyn explains how the outlook of our Solar System can predict what other star systems may look like. It is demonstrated how momentum equations are applied in astronomers’ search for exoplanets. Planet velocities are discussed and compared in relation to a planet’s mass. Finally, the Doppler shift is introduced and students learn how it is used to measure the velocity of distant objects, such as galaxies and planets.

3 – Our Solar System and the Pluto Problem

3 – Our Solar System and the Pluto Problem

Class begins with a review of the first problem set. Newton’s Third Law is applied in explaining how exoplanets are found. An overview of the Solar System is given; each planet is presented individually and its special features are highlighted. Astronomy is discussed as an observational science, and the subject of how to categorize objects in the Solar System is addressed. The Pluto controversy is given special attention and both sides of the argument regarding its status are considered.

2 – Planetary Orbits

2 – Planetary Orbits

Exoplanets are introduced and students learn how astronomers detect their presence as well as the challenges associated with it. Physics equations are explained as well as their importance in the context of the course. A number of problems are worked out to get students used to dealing with large numbers in calculating planetary masses, interplanetary distances, etc.

1 – Introduction

1 – Introduction

Professor Bailyn introduces the course and discusses the course material and requirements. The three major topics that the course will cover are (1) exoplanets–planets around stars other than the Sun, (2) black holes–stars whose gravitational pull is so strong that even their own light rays cannot escape, and (3) cosmology–the study of the Universe as a whole. Class proper begins with a discussion on planetary orbits. A brief history of astronomy is also given and its major contributors over the centuries are introduced: Ptolemy, Galileo, Copernicus, Kepler, and Newton.