Posted: Jul 16, 2018 8:19 am
juju7 wrote:Macdoc wrote:Yes ....so dealing with possible alien life could present similar problems but if it walks, slithers or swims up to you and either tries to eat you or feed you.....it's likely alive.
Mars could give us our first life that is potentially different than earth based even if in degree. Interesting times.
Silicon based entities which we are rapidly developing present a definition problem of life/alive as well....does it need to be wetware to qualify??
Silicon on its own does not present interesting possibilities for complex self replicating molecules. Silicon plus carbon does, and the compounds are thermally stable over a greater range than carbon only range: https://www.astrobio.net/news-exclusive ... ife-grows/
Another click-bait article full of hype aimed at wanna-be exobiologists.
A diatom is not a silicon-based life form. It's not even a carbon-silicon hybrid as far as metabolism goes. It sequesters silica from its environment to use in its exoskeleton. Carbon-silicon chemistry (as such) is synthesized, so we know something about the conditions required to manifest it naturally. If it occurred naturally, we'd have heard about it. Silicon in nature is not expected in its reduced form. It takes technnology to reduce silicon from silicates. Silicates (compounds combining oxygen with silicon) are widespread in nature, in case you've never seen a rock.