(Proposal ID) S16A-154

(PI) Schwamb, Megan

(Proposal Title)
Probing the Elusive Inner Oort Cloud

(Abstract)
A decade after the discovery of Sedna transformed our picture of the Solar 
System, we are still struggling to understand the history of the Outer Solar 
System beyond the Kuiper belt. Sedna's current orbit is well beyond Neptune 
and too far away in the present-day Solar System to feel the perturbing 
effects of passing stars. Some other mechanism likely no longer active in the 
Solar System today is required to emplace Sedna and a whole population of icy 
bodies on similar orbits in what is known as the Inner Oort Cloud. The wide-
field of view of Hyper Suprime-Cam (HSC) and the collecting area of the Subaru 
telescope offers a unique opportunity to probe this elusive population.  
We aim to search for additional Sedna-like objects in order to study the 
properties of this small body reservoir and further constrain the formation 
mechanism. With these HSC observations we aim to further characterize the 
Inner Oort Cloud and confirm or reject the recently proposed hypothesis that 
a planetary mass is orbiting beyond Neptune in the present-day Solar System.