I think one of the biggest questions about our universe is whether life is unique to Earth. It's pretty silly and self centered to assume that we're unique, but

I think one of the biggest questions about our universe is whether life is unique to Earth. It's pretty silly and self centered to assume that we're unique, but we don't really have any real way to confirm or deny the question outside of the ability to find signs of life within our solar system. So yes, finding signs of life on Mars is basically answering one of the most fundamental questions about our existence.