Life elsewhere in the universe is based on faith, instead of the scientific method. I am not saying life elsewhere in the universe is not logical and very reasonable. Rather, faith is defined as the belief in things not seen, while the scientific method is based on experimental evidence that is reproducible. According to the current circumstances, faith is a better description.
The most important ingredient of life is water, which is the second most abundant molecule in the universe, behind only hydrogen or H2. In terms of atoms, the top four are hydrogen, helium, oxygen and carbon, in that order. Three of the most abundant atoms within life; O,C,H, are in the top four. Because hydrogen and oxygen are numbers 1 and 3, this is why water or H2O is so common. Nitrogen is also important to life and is in the top seven.
The fundamental process for forming life is connected to mixing water and oil, which you can get from the top four atoms. Water and oil do not mix into solutions, but will phase separate into two layers. This creates a problem with respect to energy and entropy. The phase separation lowers energy, but also lowers entropy. Since the entropy of the universe has to increase, while energy has to continue to lower, chemical changes will need to appear that will allow the water and oil foundation to mix better. This occurs, in part, via a merger of organics with water via hydrogen bonding. This allows for lowering of energy and an increase of entropy. Although this may occur via trial and error, it always had a goal connected to the second law. If you look at anything in the cell, including membrane organics there are concessions to the water via added polar groups.
An interesting tidbit, is the DNA is one of the most hydrated molecules in the cell (contains the most fixed water), with the most common version of the DNA in life, beta-DNA, the most hydrated version of the DNA. The needed merger between water and organics, to optimize energy and entropy, or hydrogen bonding and bound water via hydrogen bonding, reaches a milestone within DNA. The DNA is a pinnacle goal, with respect to the needs of energy and entropy.
Nucleic acid hydration is crucially important for their conformation and utility [1093], as noted by Watson and Crick [828]. The strength of these aqueous interactions is far greater than those for proteins due to their highly ionic character [542b]. The DNA double helix can take up a number of conformations (for example, right handed A-DNA pitch 28.2 Å 11 bp, B-DNA pitch 34 Å 10 bp, C-DNA pitch 31Å 9.33 bp, D-DNA pitch 24.2 Å 8 bp and the left handed Z-DNA pitch 43Å 12 bp) with differing hydration. The predominant natural DNA, B-DNA, has a wide and deep major groove and a narrow and deep minor groove and requires the greatest hydration.
