Anybody out there?

Conservative Christian but not fundamentalist concerning origins. For within all of creation is interlocked a story of how things came to be through change. Surely God wants us to discover this. Had Adam cut down a tree on his first day he might have found 108 rings, then through study found that each corresponds to a year.  So the tree had a hidden history it was created with.  Becoming more astute, he might have postulated how oil originates from deposition, cooks from kerogen to petroleum, migrates into porous rock trapped by geology.  Now Adam has gas for his car, just as soon as he can figure that out.  Do you get a way to find oil from stubbornly insisting on a fundamentalist picture of Genesis?  We’ll leave that argument aside for the moment.  I respect your beliefs if you respect mine. 

Those who have been hard at work to find life in space are being surprised lately.  First, we have discovered life here on earth in places of adversity and in conditions never dreamed of before.  Single celled critters have been found at 300 degrees Farenheit and below zero, at 12,000 feet of depth in formations 80 million years old.  Plants and animals are too narrow in classification to include these so 3 “domains” now supercede the kingdoms we had before.  And the extremeophiles are thus included.  Some of these don’t need oxygen, indeed get energy from decomposing rock minerals.  And it is studied and argued that quite possibly Mars rocks have fossils of single cells in them, and that these kinds of simple critters may exist and have originated spontaneously all over our solar system, from Venus to the moons of Neptune. Encouraging that there is plentiful life out there.

But big organisms and especially animals like us, may be extremely rare.  How rare?  Maybe we are the lone wolves in our galaxy or even all of creation.  Why?  Because getting large animals may be the result of several fantastic circumstances that happened to earth.  First, our earth has an iron-nickel core, i.e. heavy metals, that set up a magnetic field and is coated with lighter elements.  This thin light crust combined with a highly radioactive core gives us plate tectonics.  Thirdly we have a moon that could only have been a highly rare event astrophysically.  We have a perfect-sized star with a perfect-sized large planet, Jupiter.  Without these, you get sporadic orbits, no protection from asteroid bombardments (hence life is constantly snuffed out by catastrophe), no water or air, too hot or cold, no complex evolution of species.  Atop all these is how strange plants and animals are in having cells with mitochondria and other embedded organelles which allow cells to be larger and specialized.This too, by near catastrophe.  Bottom line, Earth and animal life is rare, rare, rare.

Let me give a flavor of the arguments.  If a star is 1/3 larger than our sun, all the planets will be heavy metals and lighter elements will be driven off entirely to interstellar space.  If 10% smaller, then light elements comprise almost everything. Neither type spawns an earth. If earth’s orbit of 93M miles was 1 M miles farther out, we’d be glacial, but 4 M miles closer, we’d be greenhoused like Venus with no oceans.  But 90% of stars are 10% smaller than ours and 7% are much larger.  If stars are found in clusters or on galactic arms, the neighbor hood is too crowded.  Neighbors mess up nice circular orbits, conflict with interstellar bombardments of junk, and climates would contain no nights.  Thus even if the mix of elements was right, the atmospheres would boil off.  So scratch all but 1 out of 100,000 stars of the 200 billion in Milky Way. Our sun, 3/4 the way from galaxtic center and out between arms in a lonely location may well be among just a handful with location.  Next, galaxies are stratified with elements.  Inner galaxies are full of heavies and outer galaxies are light element laden.  Add to this elliptic and young galaxies have crowding and element problems. Scratch almost all galaxies. This does not bode well for your Star Wars fantasies about a bar scene with creatures from all over.

Within our solar system, not only do we occupy a sweet spot, but what if our world had erratic days and climes?  This would happen if we didn’t have an adjacent partner moon that is also large enough to stabilize the axis tilt and day lengths.  Without this, the spinning earth would resemble a wobbly top, which we have come to realize characterize other planets in our system.  But such a large moon is unique, maybe almost unheard of, caused from accident.  Geologic similarity with our crust, yet no core of the moon, could only have happened if early earth was bombarded by a Mars-sized planet but orbiting also almost perfectly circularly—a smaller twin. Then it had to strike at an angled blow.  The result can be modeled as a spun-off moon of lighter crust elements, but no core. No other physical explanation works. Moon stabilizes our weather, gives us tides that work coastal beaches, most important sites for origin of earth’s multicellular life.  The magnetic field protects us from asteroid bombardments so that all life doesn’t go extinct every few million years.  Jupiter’s mega-magnetics and big gravitational pull keeps us from becoming comet fodder.  Yet a smaller population of invading objects has struck the earth--almost a perfect number that has given us continents amid oceans.  More light elements brought by comets and we’d be water world with ocean completely covering and a tendency to be like the ice world Arctic ocean.  This also results from insufficient continental drift. Without continents, there can’t be forests that replace the CO2 and methane of an early atmosphere with O2. And we know that plants and forests had this effect by the massive iron and copper band deposits all around the world where oxygen made rust and precipitated these elements out of the oceans.

Next, earth is borderline Ice Earth (where glaciation completely covers everything) and we have had numerous Ice Ages when poles get corralled by landlocked oceans or continents like today. There are two episodes when this ran away into Snowball Earth—entirely covered with 5000 ft. of ice (known from deposition). Almost all life was extinguished.  But then came Vulcanism and some massive spew of ash atop the glaciation melted the snowball.  Life flourished again.  But to survive the hot-cold-hot, there were enormous evolutionary changes like the mitochondria in cells that are key to larger multi-celled organisms.  So we only get big critters if we have these rare Snowball Earth episodes--and a recovery.  Yet astrogeologists say  that almost always snowball earths are irrecoverable.  Cover a planet with white reflective ice and it stays forever cold. Hence our rare, rare twice recovery is key to evolving large critters and plants.  And in the aftermath it created an oxygen-rich atmosphere, key to growing carbon-based life.   

Beyond this are stunning new developments in understanding of the evolution of life that require earth to evolve from faint, cooler young sun to older warmer just like ours has done.  (But I have not time to write all these)  Bottom line: we’d be lucky to find intelligent life elsewhere in our galaxy because we are the result of so many crazy coincidences and accidents.  As one scientist said, “If an Almighty wanted to create an utterly unique life within the universe, this seems to be the rare circumstances he would impose.”