Are there other ways that planets could receive enough heat to sustain life besides the goldilocks zone around a star?

So I have been researching astronomy lately and this topic has stumbled across me and was curious if there are other ways a planet could sustain life without being in the goldilocks zone. I did read about Tidal Heating which can plays a role with IO but haven't done enough research on it. Was wondering if... show more So I have been researching astronomy lately and this topic has stumbled across me and was curious if there are other ways a planet could sustain life without being in the goldilocks zone. I did read about Tidal Heating which can plays a role with IO but haven't done enough research on it. Was wondering if there was anyone on here that knows a few things.
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