In the early stages of a solar system these large, baby worlds, would clear the way for Earths, by cleaning up the Ecosphere. An early newborn giant carves a gap in the disk of gas and dust swirling around a young star. The planet begins its life cycle as a small rocky sphere which acts as a core around which its gravity pulls in gas and rubble to form the gas shroud around it. Each successive gas planet to form is more condensed and smaller, as the gaseous material is gathered up first, hence the progression from HD 209458 to Gliese 876. As they move outwards each successive Roaster, or Eccentric Giant, is replaced by the next in line, and so they change lanes, like the needle on the groove of a gramophone record.

The amount of dust and rocky material in the disk in the early stages would threaten the survival of rock planets within that belt. But as each successive gas planet absorbs and clears more dust and debris within that gap the conditions become more stable and conducive to the survival of rocky planets. With less dust and rocky debris in the disk and within the Ecosphere, there is no material to collect as a gassy shroud around the rock core. The planet remains clean in its rock core state.

A more specific, labelled timeline of this sequence will be available in the 'Timeline' section of this site in future drafts.

This overall idea of course raises the questions; ‘Where do they come from in the first place, to begin their outward trajectory from a close orbit?' and ‘How can their orbits change?’ This second question is related to an impact suggested by my Pre-Cambrian shield reconstruction in 'The Visible Earths' ( see: 'Shield Re-Assembly' ).

These questions will be addressed in future drafts, in the sections; 'SOL' and 'The Invisible Earths' and listed on upcoming E7 questions.