Potential planet formation in a triple star system

Artist's impression of the GG Tau A system, including the disks of gas and dust.

ESO/L. Calçada

When Luke Skywalker stared off somberly toward the twin setting suns of his native planet Tatooine in Star Wars, he left some viewers with somber questions of their own. These questions had nothing to do with joining the rebellion. Instead, they were things like, "Could a planet like Tatooine actually exist? Can planets form in a system with more than one star?"

The formation of planets around their stars is a complicated business, and that’s when there’s only one star in the picture. Add two more stars and it can create problems for anything within their gravitational influence.

New observations of the triple star system GG Tau A addresses this issue, confirming theoretical models of planet formation in the process. The new data demonstrates that the system is capable of forming planets and suggests that planets may already be forming in GG Tau A.