  We explore here the idea, reminiscent in some respect of Von Weizsacker's
(1944) and Alfven's (1976) outmoded cosmogonies, that long-lived vortices in a
turbulent protoplanetary nebula can capture large amount of solid particles and
initiate the formation of planets. Some puzzling features of the solar system
appear as natural consequences of our simple model: - The captured mass
presents a maximum near Jupiter's orbit. - Outside this optimal orbit, the
collected material, mainly composed of low density particles, sinks deeply into
the vortices and rapidly collapses into massive bodies at the origin of the
solid core of the giant planets. - Inside this orbit, by contrast, the high
density particles are preferentially selected by the vortices and assembled by
local gravitational instabilities into planetesimals, massive enough to be
released by the vortices and to grow later, in successive collisions, to form
the terrestrial planets. - The captured mass presents a maximum near Jupiter's
orbit. - Outside this optimal orbit, the collected material, mainly composed of
low density particles, sinks deeply into the vortices and rapidly collapses
into massive bodies at the origin of the solid core of the giant planets. -
Inside this orbit, by contrast, the high density particles are preferentially
selected by the vortices and assembled by local gravitational instabilities
into planetesimals, massive enough to be released by the vortices and to grow
later, in successive collisions, to form the terrestrial planets.
