An unprecedented number of planets outside of the solar system have been found, with an explosion in the number of discoveries in recent years. Find out what has been happening in this rapidly advancing arena of human exploration, what these extrasolar planets are like, and why some traditional ideas face being thrown out.
Levison , H. F. , and M. J. Duncan . 1994. The long - term dynamical behavior of short period comets . Icarus 108 ( 1 ) : 18-36 . Levison , H. E , and M. J. Duncan . 2013. SWIFT : A solar system integration software package .
... Schrijver , H. , Bernacca , P. L. , Evans , D. W. , Falin , J. L. , Froeschlé , M. , Grenon , M. , Hering , R. , Høg , E. , Kovalevsky , J. , Mignard ... Phillips , J. A. , Thorsett , S. E. , and Kulkarni , S. R. ( editors ) , 1993.
Two decades ago astronomers confirmed the existence of planets orbiting stars other than our Sun.