icon Wandering Planets

In early 1995, in one of the first ZetaTalk writeups, ZetaTalk described the 12th Planet as a Wandering Planet spending most of its time hovering between two suns. In the March-April of 2002, the American Scientist reported that scientists had recently been astonished to find such wandering planets.

Why does the 12th Planet swing so far away from your Solar System, and why bother to return, having done so? There is a balance between the attraction of your Sun and another, unseen by you but nevertheless present and in force. The 12th Planet travels interminably between these two forces, not able to settle on an orbit around just one because of the momentum and path it originally took. It is caught. The path of the 12th Planet is such that it spends most of its life out in dark space, slowly moving from one giant tug to another.

Free-Floating Planets and Stellar Clusters
American Scientist, Vol 90, Mar-Apr, 2002

For centuries a planet has been defined as an object that orbits a star. This notion was recently upended when several groups of astronomers reported the discovery of planet-sized objects wandering through space on their own, with no parent star in sight. The discovery of these objects within dense stellar clusters has unsettled the astronomical community and raised questions about the nature of planets and how they might form. Jarrod R. Hurley and Michael M. Shara review these recent discoveries and consider how the dynamic interactions between the stars in a dense stellar cluster may free planets from the gravitational bondage of their parent stars. Jarrod Hurley is a postdoctoral investigator at the American Museum of Natural History. His research involves studying the evolution of star clusters through computer simulations. His models have helped to explain the formation of blue-straggler stars in the open cluster M67, and he has recently begun to investigate the behavior of planetary systems in star clusters. Michael Shara is curator and chair of the Department of Astrophysics at the American Museum of Natural History. His research interests include the structure and evolution of novae and supernovae, collisions between stars, and the nature of stellar populations in star clusters and galaxies.