The Hunt for a Massive Planet Beyond Pluto
Scott Sheppard
Carnegie Institute for Science



The Kuiper Belt, which has Pluto as the largest member, is a region of comet-like objects just beyond Neptune that was first confirmed to exist using the University of Hawaii 88inch telescope in 1992. This belt of objects has an outer edge, which we are only now able to explore in detail with new wide-field imagers on the worlds largest telescopes. For the past few years, our team has been performing the largest and deepest survey ever attempted to search for distant solar system objects. The ongoing search has discovered the object with the most distant orbit known in our solar system and some of the largest known trans-Neptunian objects. The uniform survey has shown that the most extremely distant objects are strangely grouped closely together in orbital space, which suggests a yet unobserved Super-Earth or larger planet is shepherding them into similar orbits that some have called Planet X or Planet Nine. I will discuss the most recent discoveries at the fringe of our solar system.