Life Requires Polar Molecules

Life Requires Polar Molecules - Watere

Chemistry is a fascinating science. The design of atoms and molecules allows life to exist. Science fiction writers have tried to convince us that there could be life out in space that is radically different from life on Earth. The subject of this discussion is not whether there is life on other planets or moons. If God created it, then it will be there, and we will find it. But life requires polar molecules.

Skeptics have maintained that to be open-minded about life in space, we must look for life based on something other than the CHNOPS. (CHNOPS is carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur.) Why not life based on silicon, iridium, cesium, iron, and chlorine?

A basic biology principle that most of us learned in high school is that to exist, life requires polar molecules. That means there has to be an abundance of a molecule with a positive and a negative end. On our planet, the molecule that meets that requirement is water.

The oxygen molecule is designed so that when it combines with two hydrogen atoms, it forms a water molecule that has a positive and a negative end. This design enables water to do a variety of things necessary for life. Water moves things around, dissolves other compounds, conveys nutrients into cells, and carries away waste. Other polar molecules, like amino acids, proteins, or DNA, could not be manipulated and used without water. Life requires polar molecules.

Astronomers have discovered methane and ethane on planets and moons throughout space, but they cannot support life because they are not polar. The media have brought attention to the moons Titan and Europa, which both seem to have oceans and rivers of methane and ethane. Other moons such as Enceladus, Ceres, Ganymede, Callisto, Dione, and Triton are chemically active and have some water, but they are dominated by non-polar chemicals. Chemical studies of the 4000 plus exoplanets astronomers have discovered do not show any other polar molecules in abundance.

Life has to follow some basic rules. One of those rules requires polar molecules in abundance for any kind of life to exist. An oxygen atom has eight electrons, but its structure allows only four electrons in its outer orbit. That is important because the outermost orbit is the only one that allows other elements to share electrons to make a compound. The four inner-orbit electrons with their negative charge cannot be shared. That automatically means that the oxygen side of any compound, such as water, will be negative, and the other side will be positive. This principle is the starting point for biochemistry, and it is a design invented by an Intelligence that established the rules for life.

When my students saw this in basic chemistry, there was always someone who would say, “Wow! Who thought that up?” As a public high school teacher, I was not allowed to say “God,” but the message is clear without being said.

— John N. Clayton © 2020

For more on this, see the article titled “Looking for Life in the Universe” by Dr. Morgan Cable in the January 2021 issue of Astronomy magazine (page 46-48). Dr. Cable is the supervisor of the Astrobiology and Ocean Worlds Group at the NASA Jet Propulsion Laboratory. Her research is about looking for life and habitability in space