Why size matters...
Everyone is running out of patience -- me included.
Orangeatheist and W*gs arrogantly refuse to read McCanney's paper which btw was published in Kronos journal, not self published.
Neither one is thus able to follow the argument.
Had they read the paper they would know why large comets are very different from small comets.
For example, scientists at Cal Tech showed that the surface temperature Comet Ikeya-Seki heated up to 1200 degrees at its nearest approach to the sun -- but soon cooled to 700 degrees.
But Ikeye-Seki was a relatively small comet -- about 3 miles in diameter.
A planetary sized comet would discharge exponentially vaster amounts of solar electricity -- and because of its mass would also remain hot for a very long time -- especially if it was captured and if it made several passes by the sun within a few thousand years.
The larger mass of a planetary sized comet would also hold the dust and minerals swept up through the tail -- which would then be deposited on the surface of the nucleus. The comet would grow in size -- and this change in mass would alter its orbit.
Small comets do not have sufficient mass to retain the materials in the coma -- which are lost to space -- almost as soon as they are acquired.
This will probably be my last post on this thread.