Saturday, November 19, 2005

Life's Molecules Abundant in Space

It has been established for a number of years that amino acids, the building blocks of proteins (proteins are long chains of amino acids), which in turn are the building blocks of life as we know it, are abundant throughout the solar system. They are found in meteorites that land on earth as well as other objects in orbit around the Sun. I remember reading about the discovery of amino acids in far reaches of space in the Milky Way, well outside of the solar system, and I finally remembered to find a reference to it.

In 2003, a collaboration of researchers from NASA, Taiwan, and Poland discovered the spectral lines of glycine, the simplest of the 20 amino acids needed to create life. These molecules were found not only in our solar system, but in systems of hot gas clouds (in the early portion of active star formation) tens of thousands of light years away. Presumably, this could have occurred when our solar system was forming some five billion years ago. As astronomers and astrobiologists look around, they find more evidence that such organic molecules are prevalent in numerous locations of the Milky Way. There is no reason not to assume that if these molecules form in our galaxy, they likely form in many other galaxies. One open question, as far as I am aware, is through what chemical processes do these organic molecules and precursors of organic life form? I’m sure it is an active area of research, and keeps alive the question that originated some forty years ago: Did life on earth come from outer space?

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