Exercise 4: Planets Applets

In the Java applet that lets you explore the possibility of a stable planetary orbit in a binary star system, notice how the planetary surface temperature changes as it orbits the two stars. If life requires the presence of liquid water (temperature range 273 - 373 K, or 0 to 100 C), would this be easily possible in a typical binary star system? Set the two stars closer together (initial a smaller) and determine if this makes a stable orbit and the correct temperature range for liquid water more likely or less likely.

In the Java applet that lets you explore the orbits of some newly discovered planet candidates in orbit around other stars, most of the orbital periods are much shorter than Earth's orbital period around the Sun. Why is this the case? Which one on the list takes longer than Earth to orbit? Why?

Exercise Solutions