The accretion of planets from planetesimalsCollisional accretion appears to be a viable, and seemingly unavoidable, mechanism for intermediate-stage from a swarm of planetesimals into a system containing a few discrete seed planets. Some other mechanism must be invoked to explain growth of condensate grains up to at least tens of meters. Gravitational instability in the particulate disk seems a plausible means of achieving that early-stage growth up to kilometer-scale bodies. The last stage of growth in which the seed planets accrete the remaining material now presents difficulties due to the isolated, circular orbits generated from the intermediate collisional stage.
Document ID
19790042793
Acquisition Source
Legacy CDMS
Document Type
Other - Collected Works
Authors
Greenberg, R. (Planetary Science Inst. Tucson, AZ, United States)
Hartmann, W. K. (Planetary Science Inst. Tucson, AZ, United States)
Chapman, C. R. (Planetary Science Inst. Tucson, AZ, United States)
Wacker, J. F. (Planetary Science Institute Tucson, Ariz., United States)