Examining the evidence for Chthonian planets : superdense exposed exoplanet cores

Abstract

Planetary cores are of interest because they provide insight into the internal dynamics and composition of planets. By using mass-radius relationship compositional analysis, this work originally set out to look for evidence of exoplanet exposed iron cores; it stumbled, however, upon potential superdense core candidates (or "Chthonian" cores). We identify 19 potential superdense core candidates, and compare them to the Fossilized Core Theory and the Giant Impact Theory of formation. Additionally, while there are 19 superdense core candidates, they represent only 11 solar systems. We find that both theories plausibly describe the formation of these superdense candidates, and note that all candidates have very typical stars similar to our own sun. Until the mass measurements of the candidates are better constrained, further conclusions cannot be drawn, however, this new type of planet could help inform planetary formation, evolution, and interior dynamic models.