"The fact that this chain of life existed [at volcanic vents on the seafloor] in the black cold of the deep sea and was utterly independent of sunlight-previously thought to be the font of all Earth's life-has startling ramifications. If life could flourish there, nurtured by a complex chemical process based on geothermal heat, then life could exist under similar conditions on planets far removed from the nurturing light of our parent star, the Sun."

Source : "Rare Earth: Why Complex Life is Uncommon in the Universe". Book by Peter D. Ward and Donald Brownlee, 2003.

You may also like: