A Tale of Carbon while on the Trail of Life: Chemistry in the Cosmos

‘We are made of star stuff,’ – words spoken by a scientist and poet who recognizes that humanity’s existence transcends time. Although the words seem trite decades after Carl Sagan spoke them, we may one day trace our birthright to a local nebula.

What’s a Nebula?

In local nebulae, hydrogen, helium, carbon, iron and other elements start coalescing. The ‘dense collection of gas and dust’ migrate to point near our current coordinates in the Galaxy. (The exact details of ‘migration’ are a subject of current research efforts.) The collection of gas and dust heat to form a proto-stellar disk, and at this point, a solar system is in its infancy. At this point, the best that most astronomers can do is to observe other ‘model’ systems similar to our own in order to gain a superior understanding.

Carina: Pre-Supernova Giant

One region of the sky that has garnered much recent attention is in the constellation Carina, or NGC 3372. Carina, a diverse star forming region in the south edge of the Milky Way, lies 7000 light years away. An outstanding feature of Carina is its massive, pre-supernova giant—eta Carina. The star eta Carina, projected by most astronomers to go supernova within the next 100 years, stands to affect any subsequent solar system that forms near to it.

A nearby supernova may trigger other stars within the nebula to implode or may launch a new solar system to form light years away. The types of stars which astronomers like to observe are the genesis of smallish, Sun-type stars. The birth of Sun-type stars would entail elements such as hydrogen, helium, carbon, and iron—also known as type V (read as five) stars. Whereas understanding star formation in the cosmos is complex, understanding the origins of our chemistry would be profound.

Chemical Elements Inside Your Body

If you take an inventory of chemical elements within your body, you find elements that were present at the birth of the Sun. Your body uses combinations of these chemical elements in the form of molecules. The most common elements that the human body uses are carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur (also known as CHNOPs). Life’s molecules arose somewhere upon the Earth almost 3.75 billion years ago and it hasn’t stopped evolving since the momentous occurrence. Why can we not re-create that occurrence? Well, perhaps, our CHNOPS model is too complex to understand.

Carbon Chemistry and Creation

Modern carbon chemistry has not caught-up to all of the natural biochemistry that is possible. Carbon is unique in many ways; the most profound is that carbon chemistry is the most stable. In just a few choice words, our carbon chemistry forms the greatest number of ‘stable molecules’ within our ‘habitable zone.’ [It is not to say that carbon-life is the only life—but it is all which know how to imagine and understand.]

The Solar System, our backyard, tells the story of our creation in puzzle-like fashion. Each planet, planetoid, comet, moon, and asteroid bears an imprint of our birth environment, and our Sun is the most telling evidence of our lives in the cosmos. The question of Earthly carbon revolves about life, and no one can unambiguously answer the question of how we came to be. However, certain research groups propose that primitive life took form through the mimicry of inorganic processes. One candidate process known as Fisher-Tropsh yields methane and begins with simple forms of carbon (e.g. carbon monoxide or graphite). Unfortunately, no research group has learned the conditions of the change from non-biological chemistry to bio-chemistry.

Biological Genesis Conditions: No One Knows For Sure

The conditions of non-biological chemistry-to-biological genesis are subject to current investigation throughout the Solar System. Titan, for instance, is saturated with organic carbon but is not known to harbor life. Enceladus, another of Saturn’s moons, contains a watery interior and one known “hotspot” that is erupting periodically with a watery mixture of its interior. Numerous other planets and moons in the Solar System beg us for exploration in an attempt to understand our origins.

Since we may truly be made of star stuff, our current efforts in understanding our origins starts with ourselves and should continue by furthering our understanding of the cosmos.

Resources

NASA. Titan’s Surface Organics Surpass Oil Reserves on Earth. (2008). Accessed November 19, 2013.

Journal of Biological Chemistry. JBC. (2013). Accessed November 19, 2013.

Evolutionary and Developmental Biology. Precursors of Life, Chemical Models and Early Biological Evolution. (2012). Accessed November 19, 2013.