Out there: what kind of life?

A team pulled together in 2004 by The National Research Council has recently issued its report on the possibility of life outside Earth.

Hat tip: Paul Gilster at Centauri Dreams. Be sure to read his thoughts on the report.

The report asks two key questions:

What are absolute requirements for life? The executive summary suggests - in decreasing certainty - four principles necessary for life to develop:

  • thermodynamic disequilibrium
  • an environment capable of maintaining covalent bonds between carbon, hydrodgen and other atoms
  • a liquid environment
  • a molecular system that can support Darwinian evolution

It also appears to hedge on the third and fourth items, which leads to second question: would we - how would we - recognize such exotic life if we encountered it?