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What do Multiple Planet Systems Teach us about Planet Formation?

Eric B. Ford
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Abstract

For centuries, our knowledge of planetary systems and ideas about planet formation were based on a single example, our solar system. During the last thirteen years, the discovery of ~170 planetary systems has ushered in a new era for astronomy. I review the surprising properties of extrasolar planetary systems and discuss how they are reshaping theories of planet formation. I focus on how multiple planet systems constrain the mechanisms proposed to explain the large eccentricities typical of extrasolar planets. I suggest that strong planet-planet scattering is common and most planetary systems underwent a phase of large eccentricities. I propose that a planetary system's final eccentricities may be strongly influenced by how much mass remains in a planetesimal disk after the last strong planet-planet scattering event.

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Eric B. Ford. 2005-12-29. What do Multiple Planet Systems Teach us about Planet Formation?. https://arxiv.org/abs/astro-ph/0512635

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