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Here's a recent radio-telescope image , ( not artist's impression ) , of a solar system forming from a proto-planetary disc ...http://www.thenakedscientists.com/forum/index.php?topic=26311.msg443799The dark circles are where planets have formed.
I have demanded the answers be given without ambiguity
How did the dust lose its angular momentum?
What about exoplanets that are orbiting in the opposite direction their host star is rotating?
Just showing a picture and saying this is so because there is a picture is very poor reasoning.
That radio-telescope image is hard evidence that the orthodox theory of planet formation is correct ... http://en.wikipedia.org/wiki/Protoplanetary_disk
Quote from: jeffreyw on 16/11/2014 23:53:39How did the dust lose its angular momentum? Collisions between planetesimals will convert kinetic-energy (angular-momentum) to heat, as will less-spectacular friction, e.g.
Quote from: jeffreywI have demanded the answers be given without ambiguityThen I am concerned that you may not understand the process of science very well.
This meaning the idea that 1 cm sized pebbles can gravitationally collapse upon themselves and form the Thomson structures seen in this picture is very poor reasoning.
... iron meteorites are derived from over 50 bodies that were 5–200km in size ... iron meteorites may have been derived originally from bodies as large as 1000km or more in size ...
The extreme pressure and heat needed to form taenite and kamacite does not exist in the vacuum, ...
... Homo-geneity of Mg isotopic compositions of diverse meteorite parent bodies suggests that 26Al was homo-geneously distributed in the solar system (Thrane et al., 2006). Therefore there would have been sufficient thermal energy from 26Al [radioactive decay] to melt cold planetesimals that accreted within 1.5Myr of CAI formation and were large enough (>20km radius) so that little heat was lost for several half-lives of 26Al ...
I wholeheartedly agree : it's km sized not "cm sized" ...