Beyond Pluto: The Hunt for a Massive Planet X
The Kuiper Belt of comet like objects just beyond Neptune has an outer edge, which we are only now able to explore in detail. For the past few years we have 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 several of the largest known objects after the major planets. The survey has shown that the most extremely distant objects, which are beyond the Kuiper Belt and influence of the known major planets, are strangely grouped closely together in space. This suggests a yet unobserved planet more massive than the Earth is shepherding these extreme trans-Neptunian objects into similar orbits that some have called Planet X or Planet Nine. Sheppard will discuss the most recent discoveries at the fringe of our solar system and what we think is out there.
About Scott Sheppard
Scott S. Sheppard is an astronomer at the Carnegie Institution for Science’s Department of Terrestrial Magnetism (DTM) in Washington, DC. He obtained his PhD from the University of Hawaii. Scott studies small bodies in our solar system in order to understand how the planets formed and migrated. If Guinness World Records had a record for the most moon discoveries, Sheppard would hold it as he has discovered over 70 moons around Jupiter, Saturn, Uranus and Neptune. Sheppard also discovered the first Neptune Trojan that trails behind Neptune in Neptune’s orbit as well as several dwarf planets that reside beyond Neptune. The asteroid 17898 Scottsheppard as well as two comets Sheppard-Trujillo and Sheppard-Tholen are named after him. Sheppard was lead discoverer of the object with the most distant orbit known in the solar system, 2012 VP113. In 2014, Sheppard along with colleague Chad Trujillo noticed all the extremely distant small bodies have similar orbits. From this observation, he predicts a Super-Earth mass planet likely exists in our solar system some ten times further out than Pluto and it is shepherding these extremely distant smaller objects into their similar orbits.