Extrasolar Planets: Homework 2

This homework must be submitted on paper or in PDF format via E-mail (mwrsps@rit.edu) before 17:00 on Monday, Oct 21.

You can also find these questions them in Lecture 2.

First, follow the directions in Lecture 2 for selecting only planets which have reliable measurements of both radius and mass. Using this subset of all the known exoplanets, perform the following tasks.

1. Make a graph showing radius (in Earth units) in linear units on the y-axis, and mass (in Earth units) in logarithmic units on the x-axis. Use limits of 0.3 to 40 Earth masses on the x-axis, and 0 to 8 Earth radii on the y-axis.
2. Add symbols on the graph for planets in our Solar System. You should find that four of the planets will fall in this range of mass and radius.
3. Draw a line on the diagram showing the location of all planets which have exactly the same density as the Earth. We could call these "rocky planets."
4. Some scientists think that this diagram shows evidence for a set of "icy planets", with densities about 0.3 times that of the Earth. Do you see any evidence for such planets? Please explain.