Date: 2012-06-02 Time: 07:00 - 09:00 US/Pacific (1 year 6 months ago)
America/Los Angeles: 2012-06-02 07:00 (DST)
America/New York: 2012-06-02 10:00 (DST)
America/Sao Paulo: 2012-06-02 11:00
Europe/London: 2012-06-02 14:00
Asia/Colombo: 2012-06-02 19:30
Australia/Sydney: 2012-06-03 01:00 (DST)
Where: Online Video Conference
Some 23% of all orbitally-determined exoplanets orbit their star within 128, with a clear concentration centred on 10 R8. The proportion has changed little as numbers grew. Not a matter of detectability but of why they are there at all (Mercury is at 83). Triton?s retrograde orbit invites a reconsideration of the main mechanism of planetary construction. Its immersion in the (56 body) prograde satellite population of the Giant Planets implies that tidal capture had been the mechanism of central body accretion until the arrival of their gas-ice envelopes liquefied their interiors, destroying their tidal attribute and halting Triton?s inward motion. Efficient tidal capture required nebular gas-drag during planetary growth, confirmed by the preserved low eccentricities of all except Mercury (so it alone suffered a late giant impact).
The second problem of planetary construction, of long standing, is to equip their growth materials with their very high (orbitally prescribed) specific angular momenta relative to that of their rotating star/Sun. Nebular action is the only conceivable agent for doing this. New insight on the physical mechanism of gravitation leads to the expectation that the Newtonian field of any gravity-retained assemblage is inescapably accompanied by a radial Gravity-Electric (G-E) field, providing a potentially over-riding repulsive force on sufficiently charged nebular ions.
The tangential velocity pattern is then not Keplerian and we show that, in the solar system example, outward G-E field action yields an adequate a.m. growth mechanism within the frame of our new scenario for planetary system formation. Its key feature is that solar/stellar passage through a second cloud gathers cold protoplanetary material whose high opacity permits protoplanetary nuclei to form very close to the star and then be pushed out successively in a G-E driven nebular disc wind, growing by tidal capture of passing objects.
Apparently we see close-in exoplanets soon after their star has left the high-opacity second cloud, exposing them to us and to their star. Now, with no disc wind to drive them outward, they accumulate in number until they vanish by evaporation.