NASA announced that there is life that lives on arsenic in a press conference. In other news, human collective minds have been blown. To be clear, it's using arsenic instead of phosphorus. To the knowledgable mind we begin to wonder: phosphorus is a HUGE part of our life (we need it for energy in the form of ATP, we use it for our DNA and RNA backbones, etc.) and it's replaceable. What else? We already know that life doesn't need water (archaebacteria can use H2S instead of H2O, for example), and this breaks another one of our self-imposed rules. Nice.
This means we have to revise one of the fundamental assumptions we make: extraterrestial life requires all of the conditions that we have for it to be viable. It doesn't. Therefore finding life is simultaneously easier and harder. Easier in a sense that less of our own criteria would be required for planets to be considered viable and therefore we wouldn't dismiss some viable planets we otherwise would have. Harder in it that a lot more planets fit the criteria.
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