3 ms·

Serious question: why is it so necessary for life to have evolved off world? What is the obsession here? Popular science type publications seem single mindedl

• sumitviii 12y ago
  Maybe because we haven't been able to conceive a single how life originated from constituent elements.
• lovemenot 12y ago
  To me, one fact about geogenic emergence of life is very suspicious. The fact that life arose so very quickly here. Certainly within 1 billion of Earth's 4.5 billion years' history. Perhaps sooner. When you consider that in ancient times Earth was molten rock at the surface it seems that, in geological terms, life arose almost as soon as it possibly could. That being the case, we can suppose that getting life going ab initio is trivial in nature (or Earth is a many-sigma anomaly). Life certainly should have arisen many times in this galaxy of 10^11 stars - many of which have planetary systems. So we presumably have life all over this galaxy, let alone the others. Whether life spontaneously arose many times independently or it got spread through panspermia is difficult to get a handle on but, given the age of the Universe (13 billion years), and the fact that distances used to be shorter, the latter hypothesis seems more intuitive to me. Either way, given the precocity of life here on Earth we may reasonably suppose the galaxy to be teeming with the stuff.