With the advances in detecting planets around distant solar systems, scientists are revising theories about planet formation in our own solar system. The BBC News has several interesting stories: <a href="http://news.bbc.co.uk/low/english/sci/tech/newsid_555000/555473.stm">Jupiter gave birth to Uranus and Neptune</a> (the theory goes that very large proto-Jupiter broke up and formed Uranus and Neptune and the Earth may not have formed where it is today), <a href="http://news.bbc.co.uk/low/english/sci/tech/newsid_524000/524757.stm">By Jupiter! Confusion over planet</a> (the 1995 Gallileo probe discovered that Jupiter has much more of the heavy gases than can be accounted for with gas left over from the Sun's birth; scientists theorize that Jupiter may have migrated in from the Oort cloud). Each theory contradicts the other (was Jupiter formed close or far away?). These theories provoke in me the same sort of wonder that must have greeted the ears of people when they learned that Earth revolved around the Sun. This story is obviously not finished and perhaps the common hobbyist astronomer may make a name for himself with further research.