People mention my PhD in astrophysics and ask me about scientific discoveries. Lately that meant asking about the possibility of flowing water and life on Mars.
My work—high-energy particle physics followed by helping build an x-ray observational satellite—barely touched on observing and exploring planets. For that matter, at this stage of our ability to explore off our planet, I prefer putting resources into non-manned exploration over manned. I don’t see great value in putting people into space relative to what unmanned expeditions could achieve and I see great costs and risks.
As for the possibility of finding life on Mars, or anywhere besides Earth, I would rank it as one of the most important discoveries ever, even if it were a simple life form. Or even just as self-replicating complex molecule. I’ve always loved physics most of all the sciences, though Darwin’s discoveries compete.
But discovering life on other planets, Mars or orbiting a star besides our Sun… I can’t imagine what we could learn or where it would lead.