Planetary Coalescence or Condensation – Which is Normal?

One interesting quote from the article suggests the two classes of stars that may be out there:

They find that those
systems with observed giant planets show no evidence for a
debris disc, whereas, those systems which display evidence
for a debris disc are not directly observed to harbour giant
planets.

If the debris disk was required for Earth to form as we know it, Earth-like planets may not be as common as we thought.

But really, who needs Earth-like planets, anyway?

3 thoughts on “Planetary Coalescence or Condensation – Which is Normal?”

  1. I see a few obvious factors to consider. Confirmation is left as an exercise for the reading deities.

    • Spin: A cloud with more spin should be flatter. The spin would also tend to cause objects which are more dense to move inward.
    • Density: A cloud with less heavy metals would have fewer planets made of them. Our system seems to have been seeded by two iron sources.
    • Wind: The Sun may have ignited earlier than in systems which have huge gas giants, and blown the lighter material further away. A nearby star might have had a similar effect in blowing away gases during our formation: particularly notable is the supernova blast wave from the second iron seeding might have participated in that.

Comments are closed.