Is the galaxy big enough to host randomly occurring life?




Let's imagine you are a hypothetical being looking for randomly occurring intelligent life within our Galaxy. You contact your local galactic real estate broker, and together you begin the search.  There are an estimated 100 billion stars in the Milky Way Galaxy, so there should be plenty from which you can choose. However, there are many things you must consider on your search.

Galactic Survivable belt

You've got to pick out a star in a place where life can survive. Galaxies have a belt where life can theoretically exist. If a star system is too close to the center of its galaxy it receives too much radiation from supernovas, and x-ray from the supermassive black hole at its heart. These worlds would be sterile. However, closer to the outer edge of the galaxy, the stars are older and don't have the heavy elements needed for terrestrial planets, and advanced life. Too close to the galactic center and the star system is sterile, too far away and life is impossible. Based on their location and age, 99.7% of stars in the Milky Way Galaxy couldn't support life. You've narrowed your search substantially. You now only have 300,000,000 stars from which you may choose.

Astrosphere  

You need a star with the proper Astrosphere. The universe is full of cosmic radiation, which is deadly. A star emits stellar wind that pushes that radiation back. Each star creates a shell of protection. If the star doesn’t emit enough stellar wind, life on the surface of local planets can’t survive the cosmic radiation. However, if the star emits too much, then it can impede or even bring life to extinction. About 96% of Stars do not have the right mass to create a life sustaining astrosphere.

Ultraviolet Balance 

Now you have to consider what type of lighting is available because life is very sensitive in some parts of the spectrum. Too much Ultra Violet destroys DNA. If a star is visible, then it is sending out UV. However, for life to develop, It can’t be too much. Only a small number of stars have both the right amount of UV at a distance that can sustain liquid water on a planet. Stars below 4600Kelvin are off the list. Also stars above 7100Kelvin can't support life either. About 92% of Main Sequence Stars won't support life because of issues pertaining to its UV band.

Star Stability 

Now to complicate this, the habitable zone of a star system moves. That’s right it moves. That’s because the star changes in luminosity throughout its cycle, and throughout its life. If the habitable zone moves out of range, all life that does exist on a planet will die. By this estimate, 96% of stars are not stable enough for prolonged life.

Light quality, astrosphere, and stability are all related so we will lump them together. Even if we are being conservative, these three aspects exclude about 96% of all available stars. So you've narrowed your search once again. You now have 12,000,000 stars from which you may choose.

Planet Presence 

Life can't live on the star, so there needs to be some terrestrial real estate. You're looking for stars with planets.  No problem, most stars have at least some planets. Scientists think the average number of planets per star is around one, although even this is still being researched. Let's be generous and say that every star in the Galaxy has at least one planet. We now have 12,000,000 planets from which we may choose. Those are pretty good odds, right?

Water Habitable Zone 

Surface temperature must be in a narrow range for liquid water to exist on a planet. Too cold and it's all ice. Too hot, and it's all vapor. Outside of our solar system, it's believed, 1 in five planets reside in this orbital range. That means that 80% of planets discovered cannot support life because any water they do have would be ice or vapor. Even for those in the right range, it does not ensure the presence and abundance of water.  We have narrowed our search to 2.4 million planets.

Tidal Locking

When an orbiting body is tidally locked, it means that only one side ever faces the object it’s orbiting. Our Moon is an example. If this happens with a planet, the sunny side becomes blazing hot and the dark side incredibly cold. Life is very unlikely in a world that doesn’t rotate properly. Of around 218 orbiting objects in our solar system, around 61 of them are or believed to be tidally locked. If this proportion were average across the whole galaxy, this would mean another 28% of planets are too lethally hot, or cold for life to survive. We've narrowed our search to 1.7 million planets.

Planet Size  

If the planet is too small plate tectonics, which is vital for planetary life, would not occur. It would be geologically dead as Venus is. Secondly, there is a minimum gravitation threshold for maintaining an adequate atmosphere.  If the planet is too massive, life as we know it couldn't work. 83% of star systems do not have an Earth-sized planet. We've narrowed our search to about 293,760 star systems.

Planetary Obliquity 

Obliquity is the tilt of the axis at which the planet rotates. Without an obliquity, a planet has no seasons. With too much obliquity the seasons will be too violent to sustain complex life. Neptune, Saturn, Mars, and Earth all have a similar obliquity, and probably would be survivable if all other factors were equal. The rest of the planets have an obliquity that would either destroy or make complex life extremely unlikely. So that's 4 out of 11  (I'm including Pluto, the Moon, and the Sun). So if that was average for the Galaxy, about 64% of planets have an obliquity that, likely, would not be life-sustaining. You have narrowed your search to 105,753 planets. The pool is getting smaller.

Orbital Eccentricity 

Elliptical orbits result in variations in the planet's average temperature. The more elongated the orbit is, the more violent the climate change through the year. The orbit has to be close to round to sustain a  consistent average temperature. Nothing orbits in a perfect circle, but Earth's is close. Mars' orbit is more elliptical than Earth's.  Mars is about 43 million Km farther away from the sun on the long end of its orbit than it is on the short end. If Earth's orbit did that, we'd be dead, because we would spend a lot of our year outside the habitable zone. Even if we had the average solar system eccentricity, it would still be a difference of 19.4 million Km. Even with that average elliptical orbit, life would be decimated if not destroyed. Out of a list of 65 orbiting objects in the Solar System, Earth has the 3rd most circular orbit and is not far from 2nd place.   Earth's orbit is unusually round, statistically uncanny, and magnificent for life. Around 90% of known orbits within our solar system are deadly, even if everything else was properly life sustaining. We're down to 10,575 planets. The pickings are looking slim.

Electric Wind  

Electric wind Is an electric flow that can carry water vapor and atmosphere away from a planet. If it's slightly too high, the planet loses atmosphere, higher still and it loses it’s water as well. Venus, which measures at around 10 volts, is parched because of this phenomenon.  Earth, on the other hand, possess an atmospheric electric field weaker than 2 volts. Scientists are currently studying whether this could have occurred on Mars as well. There is not much data on this subject yet, but of the two well measured planetary electric fields, 1 out of 2 have been too high to sustain life. Although, it’s likely that this number will increase as more data comes in let’s just stick with the numbers. Of the planets measured 50% have a known electric fields too high to sustain life. We've narrowed the search to 5,287 planets.

Planet Rotation Rate  

A planet with an iron core must rotate fast enough to create a dynamo effect. This results in a magnetic field around the planet that protects its atmosphere from being carried off by stellar wind and offers further protection from the radiation in space. However, if it rotates too fast, it will stress the crust of the planet and induce more frequent and violent volcanos. The Climate would become hostile. Beyond this, if the days are too long, the day-time heat build up is too severe for life. If the nights are too long, life dies in the freeze. In our solar system, six our of eight planets have a rotation rate that would probably be survivable if all other aspects were perfect. If this represents the average throughout the galaxy, that means that 25% of planets are hostile to life because of their rotation rate. I know it's getting dire, but we still have 3965 planets available.


Orbital Length

If the year is too long, the seasons will cycle too slowly to be of benefit. If the year is too short, then the seasons pass too quickly to offer their replenishing effect. Neptune, for instance, takes 165 years to make one orbit. If Earth had that orbit length, winter would last the equivalent of 41 years. Provided that everything else was life-sustaining, long orbits would either limit life to regions or exclude it all together. Only three out of the eight planets in our solar system have year lengths that would work for life as we know it. If that were the galactic average, it would narrow our search to 1487

Atmosphere Composition

12 of 13 bodies in our solar system that we've been able to measure have either no atmosphere or one that is toxic to life. If that is average for the galaxy, it will narrow our search to 114 planets.

Plate Tectonics

Long term life requires plate tectonics. Earth and, it's believed that Mars as well have tectonic activity. If that ratio of 2 out of 8 is average for the galaxy, it narrows our search by 75%. So we're down to 28 planets.

Gravitational Fence

Any star system that is going to sustain life long-term needs a few large bodies in outer orbits. Meteorite impacts are dangerous for life. Jupiter, Saturn, Uranus, and Neptune act as Earth's barrier from flying space junk. Let's say that we need a system with at least four planets, three of which are large and in outer orbits. So since each star has an average of 1 planet, that means that this cuts our search by another 75%. We're down to 7 available planetary systems, each of which must have at least one planet in the habitable zone. That means we're down to 7 planets. Only about 7% of discovered star systems have a Jupiter or larger sized planet. 7% of our remaining 7 star systems shows that we've met the end of our search. We are out of possible locations where life could randomly occur.

We've run out of planets even though we haven't considered these other life requirements. 

Presence and abundance of water
Atmospheric pressure
Nutrients
Planet's rocky composition
A moon
Binary Star Systems
The rarity of an ozone layer
The unknowns concerning abiogenesis.
And about a million other things.

So, whether life could randomly exist is still up for debate. However, it seems that our Galaxy is not big enough. It just doesn't have a large enough sample size.

However, we are faced with this powerful fact. Life does exist. Life exists in a corner of the galaxy, solar system, and on a planet that is perfectly suited for it. It'd be easy to think when we look at the number of stars; that life is a fore drawn conclusion. However, we know enough now to be sure that life requires help. The galaxy is too hostile and too small for us to be statistically confident that life could occur randomly.

There is another explanation, however. What if the placement of life wasn't random. What if we are here on purpose.

When you consider what we currently know about the galaxy, intelligent design makes much more sense than randomly occurring life.

Note: Much of the above estimates are based on articles and sources that you can find below.

Sources:
https://en.wikipedia.org/wiki/List_of_Solar_System_objects
https://en.wikipedia.org/wiki/Tidal_locking
http://www.keckobservatory.org/recent/entry/one_in_five_stars_has_earth_sized_planet_in_habitable_zone
http://lasp.colorado.edu/home/maven/files/2015/11/Electric-Mars_The-first-direct-measurement-of-an-upper-limit-for-the-Martian-“polar-wind”-electric-potential.pdf
https://en.wikipedia.org/wiki/Solar_analog
https://en.wikipedia.org/wiki/Planetary_habitability
uniqueness: http://www.reasons.org/articles/rare-sun
https://en.wikipedia.org/wiki/Galactic_habitable_zone
http://newsroom.ucla.edu/releases/ucla-scientist-discovers-plate-237303
http://www.popsci.com/science/article/2012-01/new-exoplanet-analysis-determines-planets-are-more-common-stars-milky-way
https://www.nasa.gov/mission_pages/kepler/news/17-percent-of-stars-have-earth-size-planets.html#.V5zTQ1cw38s
https://lcogt.net/spacebook/what-are-requirements-life-arise-and-survive/
http://www.nasa.gov/image-feature/kepler-planet-candidates-january-2015
http://www.learnastronomyhq.com/articles/15-goldilocks-factors-that-allow-life-on-earth-to-exist.html

The King and Queen Planet Do A Dance


I've been looking forward to tonight for the entire month. 24 days ago I serendipitously made a search on planet conjunctions (when two planets have an apparent pass near each other). To my excitement Jupiter and Venus would do this exact thing at the end of June 2015. It's nearly impossible if you've been outside in early evening this month not to have noticed the two bright dots growing steadily closer together in the low western sky. Since Venus' orbit is short it only ever is visible in early morning or early evening. Here is what it looked like tonight to the naked eye.


Once the sun is down the clock is ticking if you want to see this phenomenon. It follows close behind the sun below the horizon so there wasn't much time to get the telescope set. I had already pulled the observatory roof back, but I didn't have the telescope aligned. I began trying to get my scope aligned, but was getting a hardware malfunction. Since my time was running short I decided to run the alignment manually. Normally I'd spend the hour or more to get the problem ironed out, but I didn't want to miss getting a good photo. By the time I was ready to take a shot the King and Queen planet were already beginning to dip into the trees in the above picture. I didn't have any time to get the exposure balanced and the focus sharp. I just had to snap a shot if I wanted to get anything. To my eye, the two planets were clear in the eyepiece, it's unfortunate that I was unable to spend the time I needed to get a great shot, but I'm still happy with what I got.


The cluster of dots at the top is Jupiter and his visible moons Ganymede, Europa, Lo, and Callisto. The bottom bright spot is Venus. It's often called the sister planet to Earth because of her similar composition and size. She's super bright partly because her atmosphere full of shiny sulfuric acid clouds. Below is a labeled diagram of Jupiter and his moons from my stellarium software.


It was an enjoyable couple of hours. My wife and brother-in-law came and sat in the yard and talked as I went full nerd. Looking at the stars is such a great reminder of the amazing creation we have been allowed to enjoy.

A Fresh Slice of Sky

We've got a brand new slice of sky... Well I suppose it's not brand new, but the location, and removable-roofed building we'll be viewing it from is as fresh as a pile of baby ducks.

It's only 20 feet from my back door, but it feels like a sanctuary where I can commune with the divinely inspired sky. Being under the stars offers a chance to worship God in a way that the ancients understood much better than we do today. I'm thankful that God allowed us to have the resources to make this little observatory happen.

So I thought I'd share a little video with you to show you the effort that goes into moving this telescope, and why it became important to have a stationary observatory. This scope weighs in about about 300 pounds so simply wrestling it up onto the tripod was out of the question. I have to warn you, I had my shirt off when we shot this video, so It gets a little sweaty.






Orion Nebula

I went out tonight to get a view of 2004 BL86. It is an asteroid that is passing by Earth. I got the telescope aligned and ready. I charted the path of the asteroid, and waited for dark.

I had done some adjustments to the telescope. One of which was removing one of the finder scopes and placing it on a tripod. I didn't have any particular reason for this, but it came in handy.

My dad showed up after dark to come have some fun. He manned the 80mm Orion scope I had placed on the tripod, and I operated the big boy.

We peered into the vast reaches of space for a few hours, but couldn't find the asteroid. It was fun having company though (thanks Dad). I watched stellarium, which was tracking the asteroid for us, but we just couldn't find it in the sky. It was to faint to see with the naked eye, the planets just didn't align... so to speak. Dad had to head home eventually.

I continued to look for a while longer, but had no luck. I decided to scroll through the available options on the scopes database. I came across the Orion Nebula, and thought it deserved a look.

The telescope slewed over and I could immediately see a nebular mass. I decided to take the back end off the scope and strap up the Canon 5D Mark 3 for a photo op. After a little calibration, I pulled the trigger on four 15 to 30 second exposures. After I cleaned up I came in and popped them into photoshop. (Click the image above to see a little more detail.)

I will say, there have been nicer images taken of the Orion Nebula. Now for the litany of excuses. I shot this from my backyard in city limits. There are street lights all around blasting the humid air with a disgusting orange glow. All things considered though, I'm pleased with this one. This is especially considering that this is my FIRST EVER nebula photo. I don't know anything about this nebula, so I think tomorrow I'll go read up on it.

This was a nice victory after a long evening that was turning into a defeat. I imagine that this colorful cloud of dust and gas is one of God's left over paint pallets from the creation of the cosmos. Space is so alive with color and beauty. This is a reminder that God not only has done great and mighty things, but he is personal enough to make them beautiful.

Well, it's 3:15am... on a monday. I need to go to bed. Thanks!

Astronomy, a Holy Calling

Does God exist? Some might say, "yes, because the bible tells me so." That's fine, but I'd go on to say, "yes, because my telescope tells me so."

One of the unique things about the Bible is that it encourages us to do science... Specifically Astronomy (among others). Whoa wait what? You thought that science and the Bible disagreed. That's what many agenda oriented dabblers would want you to think. The Bible encourages the pursuit of science. Here is a quote from Isaiah. 

"To whom will you compare me? Who is my equal?" asks the Holy One. "Look up into the heavens. Who created all the stars? He brings them out like an army, one after another, calling each by its name. Because of his great power and incomparable strength, not a single one is missing."

This is clear call to do astronomy. It's kind of a strange thought, that all of the astronomers out there are doing what the bible tells them to do. "look up into the heavens."

The next question it asks, is the question that science has been trying to answer since its four hundred year old inception. "who created all the stars?" Although it's not stated outright one of the big pursuits of cosmology is focuses on the universe's Origin. That's just a fancy way of saying, "who created all the stars." Isaiah's question is still being puzzled over. He was confident, as am I, that it should be plainly obvious that there is a master-designer for this extremely intricate place. 

The thing I gather from this verse, is that astronomy can lead us to the truth. If God's existence is the truth, then astronomy should eventually lead us there. (as it has, in my opinion) 

Where modern evangelicalism seems to discourage the sciences, the bible invites us to engage. This verse instructs us to "look up into the heavens." I am following those instructions with the biggest telescope I could get my hands on. 


The Beautiful Moon


Took some shots of the moon tonight. I made it quick since I was out till 3am last night. Thought you guys might like to see even though they are brief. These are not processed, they are just straight out of the lens.

A thought on the moon: Life on earth wouldn't be possible for any extended period without this big beautiful space rock. Scientist believe that a huge collision about 4.5 billion years ago formed the moon. Without it the oceans would die, the hydrological cycle would become dysfunctional, and the planet would start to smell like a sweaty locker room... Well that last one, I'm not sure about.

The point is, that this huge rock is mechanical evidence that someone is watching out for us. I really believe that God fine-tuned our solar system to perfectly sustain life. Things just work too perfectly. The odds that we just arrived here as a result of chance, is over the moon, so to speak. Anyway, I'll stop yacking. Here's some shots form my scope. Enjoy.