The Oort Cometary Cloud -- Fact or Fiction?

by Hans Rickman (Uppsala Observatory)

Friday 30 Oct 2009, 10:30 → 12:00 Europe/Stockholm

FB42

I will describe the arguments involved in Oort's (1950) hypothesis about a distant reservoir of comets occupying the outermost region of the Solar System, and review the important progress made in the 1980's that led to a view that the Galactic tide is the main perturber of the cloud and the reason we see a flux of new comets. I will also introduce an important discovery of the 1990's: the Scattered Disk, and its relation to the Oort Cloud. Recent discussion of the role of the Scattered Disk has even led to a questioning of the cloud's very existence, and I will show how my recent work fits within this discussion by emphasizing the importance of the stellar encounters. Finally I will indicate some future directions of research. Host: Andrej Kuutmann