What if theres Another Earth?

[Mary Ann]

As I have been reminded constantly, we are talking about facts. So, why are we discussing this subject? It's speculation and whatever is said is not supported by the scientific facts as known at present.

There is speculation, yes, but the speculation is supported by the scientific facts which are known at present. That knowledge is very much incomplete, of course, but by using the facts we do know we narrow down the search for other planetary bodies which may harbour life.

 

[Gov Kodos]

Or moons, for all we know several of the moons with the Sol System could have life. i.e Europa. Even here on Earth haven't we discovered life were we didn't think it could survive, the deeper parts of the ocean?

While the presence of life in the variety of extremes found on Earth can give us an appreciation of the possible tenaciousness of life forms, it tells us only how widely evolution can go on Earth and tells us nothing of how life might start at all, or the conditions needed for it to start either here or elsewhere. Finding life on Europa or some other part of the solar system would be a great help toward postulating with some confidence on that subject.

Unless there being life at one of the most extreme habitats may itself be the clue that its origin was there. Within the past few decades, hydrothermal vents have been proposed as the place where life began.

Cave environments also have extreme conditions, many of which may be similar to the early Earth environment and give some thoughts on life's origin. Such extreme environments are a reasonable place to look for where the chemical became the biological as it seems a reasonable hypothesis that life would start in conditions where chemical reactions can be volatile, constant, and have a variety of hydrocarbons to muck about with. Now, how far off such conditions as known now might imply the possibility life can start elsewhere in the solar system is an open question, certainly, but one only finding life can help us answer.

 

[PurpleBuddha]

As I have been reminded constantly, we are talking about facts. So, why are we discussing this subject? It's speculation and whatever is said is not supported by the scientific facts as known at present.

All scientific inquiry begins with a discussion or examination of the unknown. Addressing that is the purpose of science.