SETI Institute Principal Investigator
In Earth’s early environment, life began under the competing demands of freedom and stability. For life to begin, chemicals needed to travel freely enough in their watery environment to make contact with other chemicals. But the complex molecules formed during these encounters also needed stability in an environment prone to rapid change. Chemist Art Weber has discovered chemical reactions that give rise to just such structures, similar to those that may have provided a safe harbor for these early molecules that were the precursors of life.
These chemical containers, or spherules, provide a marvelous solution to the competing demands for the chemical processes that lead to life. By providing a safe environment for the small molecules involved in these self-perpetuating reactions, these cell-like spherules could prevent the rapid dilution of key chemicals into the surrounding aqueous environment. These spherules are just viscous enough to slow the escape of molecules formed within by chemical reactions. Thus, the spherules might serve as sites for the multiple reactions needed to create more complex molecules.
So far, Weber’s research has shown that colonies of spherules can be generated using chemicals present in Earth’s early environment. As the next phase of his work, he will study the way these colonies grow, tracking the development of individual colonies over time.
In addition to learning more about the structure of these cell-like spherules, Weber also seeks a better understanding of the chemical reactions that drive their development. Though he has already identified several ways to generate spherules, there may well be others—perhaps even yielding spherules capable of storing molecular information in their sequences, somewhat akin to the information-bearing DNA molecule found in all forms of life on Earth today.
Image 1: Spherules from ribose+gama.
Image 2: Spherules from deoxyribose+gama.
Click on each for a larger view.
- SETI Institute Explorer, Special Edition 2005