The mast camera of Curiosity has found methane plumes and carbon-based molecules in the layered buttes of Mt. Sharp on Mars. The plumes are not considered an “active” source, but the 5.5 parts per billion rose to nine before falling to zero. Four types of rock were drilled, and one released dichlormethane and dichlorbenzene as well as chlorobenzene. A cooking process was noted as making changes. (Cosmos 12 Jan.2015)
Such cooking procedures may have altered results done by Viking I. Oxygen releases ceased after a short time and results were tabled, though they indicated a reaction that could have been found positive if
a H2O2 (hydrogen peroxide) solvent for life, not water, was assumed.
The point is this: techniques for proving the existence of exo-life need to be designed with a minimal use of procedures that could alter results. When experiments are designed, various life forms and their
off-beat requirements should be considered. We used to think life required sunlight as an energy source; now we know that methane as well as sulfur can drive microbe-based communities.
Recent findings also indicate that life can be amazingly varied and capable of inventing techniques for survival. Bacteria and plants can communicate with chemical releases. Some life forms have gear wheels
that power their hopping mobility, as pictured in the article “living Large” in Scientific American January 2015.
In that same issue, Rene Heller talks about “super-Earths” that may have produced life under different conditions from ours. Though Earth has many life-friendly features—it’s a steady middle-aged star providing a habitable zone, plate tectonics and a protective magnetic field. But large areas—deserts, open oceans and frigid poles—are devoid of life. In half a billion years Earth will be too warm for life, but other stars like K dwarfs could last longer. Larger planets could provide a thicker atmosphere or flatter lands dotted with shallow seas, a larger rocky core, and a powerful magnetic field, or more volcanism and less plate tectonics.
However, the search for extraterrestrial life has to remain focused. As Chris McKay suggests, we need to follow carbon, since we know it works here on Earth. Even more important for life is the apparent need for liquid water. McKay notes that he has never found a life form on Earth that doesn’t need water. Even in the dries locales, he has found dry desert microbes who specialize in conserving water.
Along with water, rocks may point to likely exohabitats. In the American Geophysical Union’s blog Geospace of January 2015, Nanci Bompey suggests that Kepler should focus on planets that are 1.6 the size of Earth or less, orbiting in the Goldilocks Zone of their suns, where water is liquid. There, oceans are likely to exist for billions of years, as has ours.
Already more than 900 exoplanets twice the size of Earth or smaller have been found. Estimates of habitable planets in our Milky Way Galaxy now stand at 17 billion. We are most probably not alone, given the
irrefutable fact that life must follow universal laws detailed in what we call chemistry and physics. Microbes are most likely, and intelligence may not be a prime feature in life out there, as evidenced
by the fact that sharks have survived for 400 million years on Earth with a very small brain.
Author of The Archives of Varok
The View Beyond Earth (Book 1. Rewrite of A Place Beyond Man 1975)
The Webs of Varok (Book 2.)
Nautilus silver award 2013 YA
ForeWord finalist 2012 adult SF
The Alien Effect (Book 3.)
An Alien’s Quest–Reconciliation and Hope (Book 4. coming in 2015)
Excerpts, Synopses, Reviews, On Writing, Characters and More-
Other Book Reviews- www.goodreads.com/Cary_
How the Hen House Turns- www.ladailypost.com
Complexity, Bio, Bibliography and Links- caryneeper.com
Astrobiology- astronaut.wpengine.com search:Who’s Out There