Thursday, May 3, 2012

Why search for Aliens?

Gliese 581c  NASA Image

The search for extra terrestrial intelligence has been going on for fifty years and still we have not found anything concrete. The recent discovery of "earth-like" planets like Gliese 581 c is re energizing this effort. Will we ever encounter intelligent life in the cosmos? If there are other beings in the universe where are they, and why haven’t they said hello?

In thinking about this blog I came to realize I have many more questions than answers.

What would it mean for our human civilization to discover that we are not alone? Some UFO enthusiasts claim that governments are already aware of intelligent visitation of our planet, but for whatever reason they are keeping it secret. One of those reasons might be the social repercussions of knowing that aliens exist. How would people of faith interpret first contact? Any interstellar civilization would have to be far more advanced than us. Would the fact that far more powerful beings are hanging over our heads induce mass hysteria?

Stephen Hawking, one of the most respected and renowned physicists of our times, argues that we should not broadcast ourselves, that it may be dangerous to contact alien life. After all, we have no knowledge of intent. When it comes to first encounter between “primitive” and “advanced” societies we only have human history to go on and it’s not a pretty picture. What if they want to assimilate us, enslave us, or simply wipe us out?

Gliese 581d NASA Image
The late Carl Sagan argued that any civilization capable of interstellar travel would de facto be benign. The argument goes that overly militant civilizations would not have survived their atomic age or other potential ages of technologically-induced oblivion. Only beings advanced beyond such aggression would have made it to the stars, so we have nothing to worry about. If you had to guess, which do you think it is?

I think it comes down to the fact that we are a curious lot and we just need to know one way or another. We will continue to explore space for many reasons: for resources, for entertainment, for scientific knowledge, and for prestige. Finding extraterrestrial life is central to all those rationales. If there’s one thing I’m sure of it’s that we’re going to keep looking.

The Rift Valley and Evolution

NASA Image, Rift Valley
It's incredible to think about all of the natural forces that came together to create a sentient species on this little blue planet of ours.  There are so many interesting ways to approach the question of our origins. The Great Rift Valley in Africa is a place that elicits such conversations.

What can  geology, the study of rocks and the physical earth, tell us about human origins, for example?  The crust is constantly on the move due to the internal heat of the earth’s interior. Along the Pacific rim, the sea floor is forced back into the depths of the earth forming a vast ring of volcanic fire;  In India, the Himalayas rise as the plates crush into each other.  How can any of this relate to human evolution?

In East Africa the land is being literally ripped apart by the same great forces.  A new ocean will soon sever the continent apart and the horn of Africa will become its own separate land. The African Rift Valley also happens to be the place where our first human ancestors evolved. Could there be a connection between the colossal forces working within the earth and the evolution of life and of human kind?

NASA Map of Rift Valley
Life has blossomed on earth due to the geologically active earth’s interior.  It is the reason why our planet has a magnetic field. Without that field life would be in deep trouble as it protects the earth from the sun’s periodic ejections of radioactive particles. The magnetic field also keeps the atmosphere from being slowly ripped away by the solar wind. Just look at poor Mars as an example of planet that has cooled and lost its shield.

But as far as the human story of evolution, the influence of geology may go further than that. Evolution is all about adaptability. Over the course of about five or six million years the development of hominids may have been spurred by the geomorphic changes happening across the African Rift Valley landscape. As its geology changed, bodies of water formed and disappeared, the climate became cyclically wetter and drier, and in turn the surrounding ecology adapted.

Every creature has evolved in its own unique ways. Nature is amazingly creative in that regard. Perhaps, changes in the Rift Valley favored hominids that were cleverer, more able to survive by using intellect, in turn, encouraging early humans to develop larger brains, and leading ultimately to us.

There were also global climatic changes during this time, possibly related to plate tectonics, as well as changes in the relationship of the earth and sun. Earth has experienced a few dozen ice ages in the last few million years, each one radically changing life on the planet. All but one hominid species went extinct. Climate change is no hand maiden.

In any case, a particular combination of species, land forms and climate change in the Great Rift Valley is probably why you are reading this right now.

Now that’s something to think about. There seems to be a lot that goes into making sentient life, and it seems to be a fragile process. Perhaps it is quite rare in the universe, but I doubt we are the only example, as we now know there are likely tens of billions of planets just in our galaxy alone.

Pattern and Meaning

Earth in Space
NASA photo, Apollo 11 mission.
Who cannot help being humbled by the vastness of the cosmos as compared to the smallness of our earthly home. We are indeed a tiny dot in the universe, but I do not believe significance is a matter of size. I've always been fascinated by the dynamics of pattern -- how pattern reproduces itself in vastly different scales, and how the blueprint of the universe is intimately bound through self-replicating forms.


I revel in how the arrangements of nature are ensconced in space and time; the way patterns are displayed in our planet's landmasses, in the atmosphere and in the oceans. There is an artistry to the earth's physical landscapes that is more richly textured than any human work.

Double Helix
AAAS Image

Walking along a beach I watch the swells run up the sand, weave and merge, and return to the ocean as braided rivulets, and it reminds me of the great river systems of our world.  It brings back memories of the curls in my son hair, the capillaries that course through his young body, and the double helix of DNA that constructs his being. 

Joe and Paul in 2002

So perhaps, it is within the pattern of things that we humans can find solace in this vastness of space. The same patterns, that no matter the scale, inform us that we are an integral part of the cosmos; that our existence is as much a reflection of the universe as is the largest galaxy cluster.

Milky Way
NASA Image

Wednesday, May 2, 2012

Oxygen and Life's Wonders

from Dan Chure's Land of the Dead
What an incredible thing is life.  There are so many ways natural patterns come together in a seemingly miraculous way and create the wonders of life present and past.

The griffenfly you see in the image to the right had a two and a half foot wingspan, and for that hefty size we can thank oxygen.  The level has varied over geologic time, and was once so high it allowed insects, which breathe less efficiently through tubules rather than lungs, to grow much larger. That was 300 million years ago.  There's less oxygen now, hence no more griffenfly; see Dan Chure's, Land of the Dead for more on these fantastic prehistoric insects.

Masahiro Arai Photo
Oxygen itself arises from life, and what is is truly amazing is how self-regulating it is. Virtually all of this essential gas in our atmosphere was created through living systems like the stromatolites you see here.   For billions of years such colonies of photosynthetic blue-green algae have pumped out oxygen, making the earth a home for millions of species.  

Oxygen is reactive, meaning it likes to strip atoms from surrounding molecules. As such free radicals, oxygen atoms can cause a lot of damage in living tissue.  It's probably a good thing the level has gone down.  If it were too low, however, it would be that much harder to breathe, as anyone who's been at high altitude can attest to.  If not for nature's self-balancing oxygen level, earth would not have quite the diversity of life it does.

Oxygen is key to life in more ways than you might think.  It likes to bonds with lots of other atoms, such as hydrogen to make life-essential water.  Oxygen atoms bond with themselves and form the diatomic molecules (O2) that we breathe and metabolize energy with.  One of oxygen's preferred molecules is trioxide (O3),  also called ozone.  It resides in the stratosphere and is essential in reducing the amount of harmful ultraviolet light that reaches the planet.  Ultraviolet light is a life killer, so those griffenflies, like much of life on earth, would never have evolved.

The diverse ways that patterns in nature come together and allow our planet to teem with life seem miraculous.  The earth is nestled in what astronomers call the goldilocks zone; a place in the solar system not too hot and not too cold for liquid water to exist.  Jupiter's massive gravity well sucks up many of our solar system's rogue asteroids and comets.  In four and a half billion years Earth has experienced about five mass extinction events, and each time life had to start over.  If not for Jupiter's protection, many more impacts on our world would have stunted life further.  In the center of the earth there is a giant ball of iron spinning inside a vaster liquid ocean of iron.  The spin generates the protective magnetic field around the planet.  If not for the magnetic field, periodic solar storms would eventually strip away the atmosphere (like happened on poor Mars), and life would be buffeted with deadly radiation.

All of these things allowed for an evolving biosphere and ultimately us.

Some wonder if it is divine providence that creates these seemingly miraculous and interwoven patterns.  On the other hand, if not for all of the things that make life on earth possible I wouldn't be wondering about it, would I?  It could all be just a numbers game, as according to the most current data there are likely billions of planets just in our galaxy.

As a science fiction writer, I like to think that there are many other worlds that also got life lucky.  We are searching...