Some pretty incredible news coming out of NASA states that Jupiter-size planets exist in such numbers in our Milky Way Galaxy that they may outnumber stars 2-to-1. Also stunning, to me at least, is that these exoplanets are "free floaters", which means they are not associated with a star - they are alone in space. They may have been ejected from their star-planetary system after being formed. It is also possible that there are Earth-size "free floater" planets as well.
A joint Japan-New Zealand survey "scanned the center of the Milky Way galaxy during 2006 and 2007, revealing evidence for up to 10 free-floating planets roughly the mass of Jupiter. The isolated orbs, also known as orphan planets, are difficult to spot, and had gone undetected until now. The planets are located at an average approximate distance of 10,000 to 20,000 light years from Earth."
Read More About It: http://science.nasa.gov/science-news/science-at-nasa/2011/18may_orphanplanets/
Sky Guy in VA