Miller-Urey Experiment & Carl Sagan

One Voice in the Cosmic Fugue 

I am bidden to surrender myself to the Lord of the Worlds. He it is who created you of the dust... -The Koran, Sura 

 The oldest of all philosophies, that of Evolution, was bound hand and foot and cast into utter darkness during the millennium of theological scholasticism. But Darwin poured new lifeblood into the ancient frame; the bonds burst, and the revivified thought of ancient Greece has proved itself to be a more adequate expression of the universal order of things than any of the schemes which have been accepted by the credulity and welcomed by the superstition of 70 later generations of men. -T. H. Huxley, 1887 

Probably all the organic beings which have ever lived on this earth have descended from some one primordial form, into which life was first breathed .... There is grandeur in this view of life . . . that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved. - Charles Darwin, The Origin of Species, 1859 

 A community of matter appears to exist throughout the visible universe, for the stars contain many of the elements which exist in the Sun and Earth. It is remarkable that the elements most widely diffused through the host of stars are some of those most closely connected with the living organisms of our globe, including hydrogen, sodium, magnesium, and iron. May it not be that, at least, the brighter stars are like our Sun, the upholding and energizing centres of systems of worlds, adapted to be the abode of living beings? - William Huggins, 1865 

All my life I have wondered about the possibility of life elsewhere. What would it be like? Of what would it be made?All living things on our planet are constructed of organic molecules - complex microscopic architectures in which the carbon atom plays a central role. There was once a time before life, when the Earth was barren and utterly desolate. Our world is now overflowing with life. How did it come about? How, in the absence of life, were carbon-based organic molecules made? How did the first living things arise? How did life evolve to produce beings as elaborate and complex as we, able to explore the mystery of our own origins? And on the countless other planets that may circle other suns, is there life also? Is extraterrestrial life, if it exists, based on the same organic molecules as life on Earth? Do the beings of other worlds look much like life on Earth? Or are they stunningly different - other adaptations to other environments? What else is possible? The nature of life on Earth and the search for life elsewhere are two sides of the same question - the search for who we are. In the great dark between the stars there are clouds of gas and dust and organic matter. Dozens of different kinds of organic molecules have been found there by radio telescopes. The abundance of these molecules suggests that the stuff of life is everywhere. 

Perhaps the origin and evolution of life is, given enough time, a cosmic inevitability. On some of the billions of planets in the Milky Way Galaxy, life may never arise. On others, it may arise and die out, or never evolve beyond its simplest forms. And on some small fraction of worlds there may develop intelligences and civilizations more advanced than our own. Occasionally someone remarks on what a lucky coincidence it is that the Earth is perfectly suitable for life - moderate temperatures, liquid water, oxygen atmosphere, and so on. But this is, at least in part, a confusion of cause and effect. We earthlings are supremely well adapted to the environment of the Earth because we grew up here. Those earlier forms of life that were not well adapted died. We are descended from the organisms that did well. Organisms that evolve on a quite different world will doubtless sing its praises too. All life on Earth is closely related. We have a common organic chemistry and a common evolutionary heritage. As a result, our biologists are profoundly limited. They study only a single kind of biology, one lonely theme in the music of life. Is this faint and reedy tune the only voice for thousands of light-years? Or is there a kind of cosmic fugue, with themes and counterpoints, dissonances and harmonies, a billion different voices playing the life music of the Galaxy? Let me tell you a story about one little phrase in the music of life on Earth...

The stuff of life, it turns out, can be very easily made. Such experiments were first performed in the early 1950’s by Stanley Miller, then a graduate student of the chemist Harold Urey. Urey had argued compellingly that the early atmosphere of the Earth was hydrogen-rich, as is most of the Cosmos; that the hydrogen has since trickled away to space from Earth, but not from massive Jupiter; and that the origin of life occurred before the hydrogen was lost. After Urey suggested that such gases be sparked, someone asked him what he expected to make in such an experiment. Urey replied, ‘ Beilstein .’ Beil stein is the massive German compendium in 28 volumes, listing all the organic molecules known to chemists. Using only the most abundant gases that were present on the early Earth and almost any energy source that breaks chemical bonds, we can produce the essential building blocks of life. But in our vessel are only the notes of the music of life - not the music itself. The molecular building blocks must be put together in the correct sequence. Life is certainly more than the amino acids that make up its proteins and the nucleotides that make up its nucleic acids. But even in ordering these building blocks into long-chain molecules, there has been substantial laboratory progress. Amino acids have been assembled under primitive Earth conditions into molecules resembling proteins. Some of them feebly control useful chemical reactions, as enzymes do. Nucleotides have been put together into strands of nucleic acid a few dozen units long. Under the right circumstances in the test tube, short nucleic acids can synthesize identical copies of themselves. No one has so far mixed together the gases and waters of the primitive Earth and at the end of the experiment had something crawl out of the test tube...

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Cosmos, II-"One Voice in the Cosmic Fugue"

All living things on Earth are made of organic molecules a complex microscopic architecture built around atoms of carbon.
In the great dark between the stars there also are organic molecules in immense clouds of gas and dust.
Inside such clouds there are batches of new worlds just forming.
Their surfaces are very likely covered with organic molecules.
These molecules almost certainly are not made by life although they are the stuff of life.
On suitable worlds, they may lead to life.
Organic matter is abundant throughout the cosmos produced by the same chemistry everywhere.
Perhaps, given enough time the origin and evolution of life is inevitable on every clement world.
There will surely be some planets too hostile for life.
On others, it may arise and die out or never evolve beyond its simplest forms.
And on some small fraction of worlds there may develop intelligences and civilizations more advanced than ours.
All life on our planet is closely related.
We have a common organic chemistry and a common evolutionary heritage.
And so our biologists are profoundly limited.
They study a single biology one lonely theme in the music of life.
Is it the only voice for thousands of light years or is there a cosmic fugue, a billion different voices playing the life music of the galaxy? This blue world is where we grew up.
There was once a time before life.
Our planet is now burgeoning with life.
How did it come about? How were organic molecules originally made? How did life evolve to produce beings as elaborate and complex as we able to explore the mystery of our own origins? Let me tell you a story about one little phrase in the music of life on Earth.

Read more: https://www.springfieldspringfield.co.uk/view_episode_scripts.php?tv-show=cosmos-carl-sagan&episode=s01e02

How did it come about? How were organic molecules originally made? How did life evolve to produce beings as elaborate and complex as we able to explore the mystery of our own origins? Let me tell you a story about one little phrase in the music of life on Earth.

Read more: https://www.springfieldspringfield.co.uk/view_episode_scripts.php?tv-show=cosmos-carl-sagan&episode=s01e02