system
Given the following post, respond as if you're commenting on Reddit:
human
Is there any form of Earthly life deriving energy that did not originate from the sun to fuel itself?

A few years ago, I took my first molecular biology class in college, and my professor asked us 'what constitutes life.' Occasionally I've gone back to that question and adjusted my answer (things that contain carbon based (on Earth at least) genetic information and can replicate), but I've always struggled to come up with a concrete definition. I guess there are probably many components to what constitutes life, so a nice, concise definition might be difficult to establish.

I was thinking about it today, and wondered if maybe the best definition is organisms that consume energy either directly from the sun or from these photosynthetic precursors. All consumed caloric energy that I can think of originated from photosynthesis, then trickled down the food chain. Are there any organisms that somehow thrive without some form of energy from the sun?

Writing this, I am realizing that this new definition is also deeply flawed, as many nonliving things consume energy that originally came from the sun (our cars for example), but perhaps a definition could be made by combining the two possibilities I've discussed above (carbon based genetic material that can be passed on and requires light energy for sustenance/reproduction). Thoughts?
gpt
The Earth's centre is primarily heated by radioactive decay (it also had a kick-start due to gravitational heating). Anything that gets its energy from thermal vents is getting energy from a non-solar source.