The discovery, ten years ago, of planets outside the solar system has transformed extrasolar planets from a topic of speculation and science fiction into one of the most compelling and rapidly advancing fields of astronomy today. As described at this conference, there are now more than 100 planets known beyond the solar system. Their orbital properties span an ever increasing range in mass, orbital radius, and eccentricity, demonstrating a diversity that is both remarkable and largely unanticipated.
The diversity in the properties of extrasolar planets has inspired multiple theories of their origins. Some of these (such as core accretion—Bodenheimer & Lin 2002; see also Hubickyj, this volume) strongly favor the creation of solar systems like our own, whereas others (such as gravitational instabilities—Boss 1997; Mayer et al. 2002; see also Durisen, this volume) are likely to lead to systems with very different planetary architectures. Thus, distinguishing between these scenarios has a strong connection to an issue of an-thropic interest: the commonality (or rarity) of solar systems like our own. The possibility that multiple theories might account for the orbital properties of the extrasolar planets drives us to search beyond planetary architectures for clues to their origins, clues that may be contained in stellar metallicities, planetary atmospheres (Brown, this volume), and plausible planet formation environments, i.e., disks surrounding young stars.
Was this article helpful?