A NASA-funded study has concluded that the definition of what comprises life must be expanded. Carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur are the six basic building blocks of all known forms of life on Earth. While carbon is most commonly known - reference to carbon-based life forms, Phosphorus is critical for the energy-carrying molecule in cells and also the phospholipids that form all cell membranes.
The research has discovered a microorganism on Earth that substitutes arsenic for phosphorus in its cell components. One reason this is so interesting is that arsenic is well know as being poisonous to most life on Earth. As such, it forces researchers to re-define what they believe constitutes life forms.
Since typically researchers searching for evidence of life have focused primarily on life that would need an Earth-type environment must now broaden their horizon. And, theortically, since these microorganisms substitute arsenic for phosphorus (given similarities between the elements), could life exist substituting one of more of the other five building blocks?
Imagine the possibilities, science fiction fans and writers. I like to say readers are becoming more advanced, so credibility in stories and world building are important. This give credibility for world building in a variety of environments poisonous to humans.
So take a moment tonight and look at the stars again.
Hope you have clear skies.