Chapter 6, Problem 40EAP

Group Activity: A Cold Solar Nebula. The excess gas of the solar neb-ula is presumed to have been cleared away (by the solar wind) at a time when the frost line was located between the orbits of Mars and Jupiter, but study of planets around other stars suggests that gas may be cleared out earlier or later in other solar systems. In this activity, you’ll consider how our solar system might have turned out differently if the excess gas of the solar nebula had not been cleared away until the entire disk of gas had cooled to 50 K.

Note: You may wish to do this activity using the same four roles described in Chapter 1, Exercise 39.

a. Make a list of ingredients that will condense at 50 K.

b. Make a list of ways in which the terrestrial planets might have turned out differently under this alternative formation scenario.

c. Repeat part b for the jovian planets.

d. Discuss the likelihood that your predicted changes would match the actual characteristics of this alternative solar system.

e. Come up with additional “what if” scenarios, discussing various other ways in which the planets might have turned out differently.