Name: _________________________________           Section Number: ______

Astro 120 culminated with a discussion of the astronomical (and biological) circumstances that led to the development of life on our planet. This large problem was broken down into a series of smaller ones with the so-called Drake Equation.

Please discuss the following aspects of this equation using what you learned in Astro 120 this semester - in the last week as well as earlier in the course. Be sure all of your answers are in complete sentences and paragraphs. Also be sure to use the form of the Drake Equation we used in lecture.

a) (12 pts)
The Earth is the only known host of life in our solar system. Briefly discuss three properties of the Earth and/or its location that have made it suitable for life to develop. You must relate each of these properties to factors in the Drake equation, so be sure to say which Drake Equation factor is relevant to each property and why it is so.

b) (8 pts)
Make your own estimates for each of the terms of the Drake Equation (feel free to use those determined in class if you agree with them, or use different values if you prefer) and briefly discuss (in a complete sentence or two) your reasons for adopting EACH value. What is your final value of N?

c) (5 pts)
Should we rule out the possiblity of life in an extrasolar planetary system that has a Jovian planet inside the frost line? Why or why not?