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We explore the conditions prevailing in primordial planets in the framework of the HGD cosmologies as discussed by
Gibson and Schild. The initial stages of condensation of planet-mass gas clouds is set at 300,000 yr (0.3My) following
the onset of plasma instabilities when ambient temperatures were >1000K. Eventual collapse of the cloud into a solid
structure, dominated by water-ice and organics takes place against the background of an expanding universe with
declining ambient temperatures. Isothermal free fall collapse occurs initially via quasi equilibrium polytropes until
opacity sets in due to molecule and dust formation. The contracting cooling cloud is a venue for molecule formation and
the sequential condensation of solid particles, starting from mineral grains at high temperatures to ice particles at lower
temperatures, Water-ice becomes thermodynamically stable between 7 and 15 My after the initial onset of collapse, and
contraction to form a solid icy core begins shortly thereafter. The icy planet core, which includes a fraction of
radioactive nuclides, 26Al and 60Fe, melts through interior heating. We show, using heat conduction calculations, that the
interior domains remain liquid for tens of My for 300km and 1000km objects, but not for 30 or 50km objects. Initially
planets are separated by relatively short distances, measured in tens to hundreds of AU, because of the high density of
the early universe. Thus exchanges of materials, organic molecules and evolving templates could readily occur
providing optimal conditions for an initial origin of life. The condensation of solid molecular hydrogen as an extended
outer crust takes place much later in the collapse history of the protoplanet. When the object has shrunk to several times
the radius of Jupiter, the hydrogen partial pressure exceeds the saturation vapour pressure of solid hydrogen at the
ambient temperature and condensation occurs.
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