Astronomy 490                                  Homework #4                                         Spring 2007

 

 

Due date:   Monday, Feb 26  at start of class

 

 

Journal paper:  

   Basri and Brown 2006, Annual Review of Earth and Planetary Sciences, 34, 193

 

 

In class, you have volunteered (or been assigned) to read one of the following sections of the paper in detail:

   

      *  Characteristics:  Physics Properties of the Objects (pages 3 – 8)

 

      *  Circumstances:  The Context of Planets (pages 8 – 11)

 

      *  Cosmogony:  The Formation of Planets (pages 11 – 14)

   

      *  Culture:  The Common Understanding of “Planet”  (pages 14-17)

 

In addition, you have volunteered (or been assigned) to argue for or against a definition of the word “planet” that includes Pluto.

 

 

Assignment:

 

1.  Read the entire paper carefully.  Recall that this article was assigned as an additional

     reference on HW1.

 

 

2.  Reread the section you are focusing on.  Then write a short essay (1-2 pages,

     typewritten) summarizing the ways in which your topic area (Characteristics,

     Circumstances, Cosmogony, or Culture) could be used to define the word planet. 

     Be explicit about which objects in the Solar System would be included or excluded in

     the various possible definitions you describe.

 

 

3.  Come to class prepared to argue for or against a definition of the word “planet” that

      includes Pluto (whichever side you volunteered for or were assigned).