If we take an earth-sized planet with similar atmosphere, and put it into a P-type binary orbit, could it sustain human life? For sake of clarity, assume both stars are G-type stars and the planet is orbiting at 1-2 AUs from the stars.

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    $\begingroup$ P-type means planetary-type (circumbinary) as opposed to S-type (satellite-type) by the way. Lots of this is discussed in this XKCD what-if. If you are far enough from the binary to have a stable orbit (about 6x the distance between the stars) then they will never be more than about 20° apart in the sky, so, provided the orbit is stable, it will be surprisingly similar to orbiting a single star. $\endgroup$
    – Wyck
    Commented Sep 6, 2022 at 16:34

2 Answers 2


It’s plausible.

Research indicates that low mass binary stars may be especially suited to supporting life. Granted, this article discusses stars of a lower mass than G-type stars, and planets orbiting at greater AU, but this is a promising sign.Real research in astrophysics is being done to determine the habitability zones of binary star systems Given that this is an ongoing topic of research, and one that is fairly young, it is reasonable to have a binary star system posses the right features for supporting life.


As told here it is possible for S-Type and P-Type planets to be in habitable zone..

Studies of Alpha Centauri show that Centauri A and B have an 11 au distance at closest approach (23 au mean), and both have stable habitable zones for non-circumbinary (S-Type) planets.

Kepler-47c is a gas giant in the circumbinary (P-Type) habitable zone of the Kepler-47 system.

If Earth-like planets form in or migrate into the circumbinary (P-Type) habitable zone, they would be capable of sustaining liquid water on their surface in spite of the dynamical and radiative interaction with the binary stars.

For more details, read here and here.


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