A NEW EVOLUTIVE SCENARIO FOR THE JUPITER'S CORE?

Image: This artist's conception shows a Jupiter-sized planet forming from a disk of dust and gas surrounding a young, massive star. - NASA

Astronomers have discovered nearly 500 planetary systems each with multiple planets, and typically these systems include a few planets with masses several times greater than Earth's (super-Earths), orbiting closer to their star than Mercury is to the Sun, and Jupiter-like gas giants are also often found close to their star. [2]

In a recent paper (Raymond et al. 2016) the authors suggest an alternative scenario for the formation of the Jupiter's core: it may have formed in the innermost of the protoplanetary disk and it would later be migrated to the outer region via planet-disk interactions.

The migration of the Jupiter's core may have removed solids from the inner disk by resonance and it may thus explain the absence of terrestrial planets closer than Mercury. Finally it may also have influenced the formation of the Saturn's core.

[1] Raymond et al 2016 (accepted to MNRAS) - Did Jupiter's core form in the innermost parts of the Sun's protoplanetary disk? (arXiv)
[2] Jupiter - (Wikipedia)

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