Just going to throw this out there. Our definition of life is presently incomplete. We recognize about six elements necessary for life, but thus far all have required Phosphorous as one of them (DNA). However, Arsenic is chemically similar if you understand the Periodic Table, and there is mounting evidence that some life forms may be able to use Arsenic instead of Phospohourous. Unicellular organisms have been discovered that are capable of reproducing themselves in the absence of Phosphourous and 500 000X the amount of arsenic believed to be manifestly lethal. So right now on our very own planet we have life forms that don't share the same makeup/building blocks. Bearing this in mind...is it possible that life can exist unlike anything on Earth or in our solar system? I believe the answer is "yes", it is certainly possible and given the size of the universe, probably inevitable.
