The two best alternatives are:
- The Sun formed in a binary system.
- But why did things grow in the KB?
- Will not produce bimodal inclination distribution (I think).
- A very large, eccentric, inclined planet excited the Kuiper belt
- But, it needs to stay around longer then simulations thus far predict.
This work is supported by NASA's PGG and Origins programs.
This talk can be found at www.boulder.swri.edu/~hal/talks.html