A new planet where it shouldn't be

Fun story about astronomers discovering yet another planet around a distant sun.  I remember hearing the news a couple years ago that they finally had images of planets orbiting another sun.  Cool stuff.  The planets were huge, and there were a couple theories that popped up explaining how those planets could form.  Now a fourth planet has peeped out, and unfortunately neither theory can explain its existence.  That's why I am fascinated by science, but always cognisant of the fact that 500 years from now, they'll be laughing at most of what we thought was true.