Giant Exoplanets Have Elliptical Orbits. Smaller Planets Follow Circular Orbits

We are so familiar with our solar system that we often presume it is generally how star systems are built. Four little planets close to the star, four large gas planets farther away, and all with roughly circular orbits. But as we have found ever more exoplanets, we've come to understand just how unusual the solar system is. Large planets often orbit close to their star, small planets are much more common than larger ones, and as a new study shows, orbits aren't always circular.