Sedna as a First Generation Oort Cloud Object
(Brasser, Duncan, & Levison 2006)
- Recall that the Oort cloud forms where τd equals τq.
- If the tides are stronger, then τq is shorter
Oort cloud closer.
- Current tides are due to Galactic disk.
- Solar System formed in a star cluster
stronger tides.
- Jupiter and Saturn probably formed before the Sun left its birth cluster.
- They had to form before the gas disk went away (about 3Myr).
- Thus, there may be a 1st generation Oort cloud that formed when the Sun was in its cluster.
- Formed from Jupiter-Saturn planetesimals.
- Normal OC formed from Uranus-Neptune planetesimals.
- If true, Sedna and kin may tell us what kind of cluster the Sun formed in.