I think the problem is knowing how to define "life" and then working back to other possible implementations. As Douglas Adams framed it, "does it go squish if you step on it?"
As far as I know, the current thinking is still that life emerged (or arrived) only once on earth. One version of genetics, one implementation of life's basics, the eath-life basics. This makes it hard to generalize. It's also hard to speculate on the likelihood of such a seed event, on the basis of a single occurance. We have very little information, in Drake's equation terms, on the likelihood of life emerging given earth-like circumstances. Earth is obviously life-supporting. Why did it only happen once here, and so early in the game... As soon as the planet cooled.
For example, we could define life in terms of evolution, any evolutionary system with potential for a lot of complexity in the long term. ...we only have one example of this, earth life.
I think it's natural to start here, with earth life because that's all we know about and our speculations are very... speculative. At least we know what we're looking for this way. Earth-life can survive X conditions, therefore life can. What conditions can other types survive, if they do or even can exist? Who knows.
A lot of mystery still. Even the emergence or pan-spermia question is wide open. Even within this information bubble of earth life.. we don't know how extreme life can get. We just know about stuff that evolved to survive the extreme conditions found on earth. It's plausible (even probable) that earth-life has the potential to go even further, if earth provided more extreme niches to adapt to.
I think the problem is knowing how to define "life" and then working back to other possible implementations. As Douglas Adams framed it, "does it go squish if you step on it?"
As far as I know, the current thinking is still that life emerged (or arrived) only once on earth. One version of genetics, one implementation of life's basics, the eath-life basics. This makes it hard to generalize. It's also hard to speculate on the likelihood of such a seed event, on the basis of a single occurance. We have very little information, in Drake's equation terms, on the likelihood of life emerging given earth-like circumstances. Earth is obviously life-supporting. Why did it only happen once here, and so early in the game... As soon as the planet cooled.
For example, we could define life in terms of evolution, any evolutionary system with potential for a lot of complexity in the long term. ...we only have one example of this, earth life.
I think it's natural to start here, with earth life because that's all we know about and our speculations are very... speculative. At least we know what we're looking for this way. Earth-life can survive X conditions, therefore life can. What conditions can other types survive, if they do or even can exist? Who knows.
A lot of mystery still. Even the emergence or pan-spermia question is wide open. Even within this information bubble of earth life.. we don't know how extreme life can get. We just know about stuff that evolved to survive the extreme conditions found on earth. It's plausible (even probable) that earth-life has the potential to go even further, if earth provided more extreme niches to adapt to.