Tuesday, April 2, 2013

Aliens, Holy Crap!

While immigration is a hot topic, the aliens I would like to talk about fly around in spaceships and abduct cows and drunken farmers.

Actually not really.

Aliens definitely exist.  There is no doubt about that.  The universe has more stars than there are grains of sand on all of the beaches on earth.  I ripped that one off from every star documentary ever.  And the universe is approximately 13 billion years old.  At those time frames and scales it is certain that alien life exists.

So astronomy and astrobiology and all those related fields have not been trying to answer the question of if life exists.  The scientists have basically been asking more evidence based questions.  What does life look like on other planets?  What would be some signs of life?  Could we see life from here?

The last one intrigues me greatly.  The answer to the last question is yes.  Not that we have observed life yet, just that we don't have to travel to every star system to detect extraterrestrial life.

This is because of a cool scientist named Kardashev.  IO9 writes a great blog every now and then about him so I'm just going to direct everyone there and assume you have read it already.  http://io9.com/5986723/using-the-kardashev-scale-to-measure-the-power-of-extraterrestrial-civilizations and http://io9.com/5982820/seti-conducts-first-ever-targeted-search-for-intelligent-life-on-earth+like-planets.

Do not continue reading if you don't have a handle on the Kardashev scale or Dyson Spheres.

Anyways, the Kardashev scale basically categorizes advanced civilizations into broad categories of advancement based on their energy consumption.  It's really rough but it basically demonstrates technological advancement in exponential form.

A type I civilization can harness all of the energy of a planet.  A type II civilization, a star.  III a galaxy, IV a super cluster of galaxies.

These types of civilizations would be extraordinarily powerful and far beyond what many of us can imagine.  Even a type I civ has far more energy at its disposal than we could ever dream of using.

How do these civilizations harness this energy? One supposition is through Dyson spheres, constructs the size of solar systems that completely encompass and absorb the energy of a star.  Think of it as a giant wonderball.  What's in your wonder ball? Just a class m star.

And it's thought that an adequately advanced civilization would go rampant with these things, building them around every star in their reach.  So basically, a galaxy, or parts of one, would start disappearing as each star's light was harnessed into energy.

Corners of the universe would have Dyson spheres obscuring much of the light energy.  But you could still see them.  There would be massive heat output as well as the gravity remaining in place.  There would be signatures outside the visible light spectrum all over the place.

So we, from earth, using our super powerful telescopes, have the ability to look for alien life.

The hardest part is that if we saw them, spotted a civilization in some distant galaxy, we would still never be able to communicate with them.  The discovery of human kind would be really disappointing.  We could signal them and wait hundreds of millions of years or we could try to send a probe.  But that would take even longer.

Why is that? The speed of light.  It sucks but there is a finite speed any message can travel in the universe.

So let's run a scenario. One: we find a Voyager like object.  Traveling at several thousand miles per hour, this object transmits basic radio signals back to its home system at the speed of light.  This extremely small and dark object contains basic and enigmatic markings that give us some indication of what we can expect.  Upon spotting this object from earth, a probe is quickly built to intercept the object. Using traditional technologies it takes thirty years to build launch and intercept the object, which is barely in Sol's reach.

When we finally retrieve this object we discover that the satellite originates from a system a couple hundred light years away.

huzzah!  Except no. We immediately send a signal to the system and spend several hundred years waiting.  It's a pyrrhic victory though because the Voyager object moved so slowly that it took nearly a million years to get to us.

A lot happens in that time.

Two: we encounter a large object moving at relativistic speeds that contains colonists.  This is a likely scenario when encountering a type I civ. While the aliens can't break the speed of light, they can move at a significant fraction of the speed of light to make some sort of long distance space colonization possible.  These organisms would either have to be very long lived or have a hibernation system in place--yay cryogenics.  These organisms would likely take advantage of quantum entanglement to communicate instantly with their home world. 

And hopefully they are peaceful.  Their technology would already be far advanced from ours and any contact with us would be a cowboys and Indians scenario where we are the affable idiots accepting smallpox blankets.

These aliens could likely terraform a planet easily and eliminate any threat we could throw at them.  Even our nukes would likely lack sufficient ability in a war--mostly because it would kill us too.

If they are peaceful they would likely have the ability to harvest and devour the resources of our solar system without even coming to earth. If they want water they could go to Titan, if they want minerals or resources they could easily harvest from nearly any other planet.

In typical human fashion it would likely be up to us to screw everything up.

Three: we encounter a type II civilization.  Forget military conflict.  Forget any notion of self determination.  We are at the complete mercy of the aliens that would visit this solar system.  It is highly likely though that this encounter would never happen.  By this stage aliens have no use for a world as primitive as ours and would prefer to avoid crushing ants between their fingers.  There are billions of stars near us and many are uninhabited and have more energy available than Sol.  We are insignificant.  We could possibly see them though.

Rather, we could watch as a star dims during the construction of a Dyson sphere nearby us.  If we tried to make contact our satellites would be destroyed or disabled.  A manned mission would be stupid. Contact with a race at that level of technology would be far beyond much of our comprehension. Seriously, we would be ants to them, cute pets perhaps but nothing more.

The other types of civilizations we would encounter can only be described as gods.  Civilizations that can perform miracles.  We don't want to screw with these guys.  Seeing them in action is already too close.

In conclusion, aliens--we should be super freakin' scared.