The following is a list of things required in order to maintain/ sustain complex life- (outside of the required chemical processes at the cellular level). The point of the list is to show how very incredibly lucky we are. We won the cosmic lottery! Or is there a purpose for our existence? Does Occam’s Razor really favor one designed universe over multiple chance collisions & multiple lucky events? Does science really favor the chance collisions & multiple lucky events scenario? (also mixed in are the ways the factors aid in scientific discovery)
ID vs. sheer dumb luck- You decide.
Factors for complex life:
1.
Liquid watera. Enough surface water to help regulate the planet’s temperature
b. Good solvent
c. Transports minerals
d. The presence of liquid water means the planet is in the habitable zone of it’s local star (Sun)
e. The presence of liquid water defines the CHZ (
Circumstellar
Habitable
Zone. The CHZ of our solar system lies between Venus & Mars. Some scientists have narrowed it to:
-If the Earth were 5% closer to the Sun – too hot, no liquid water
-If the Earth were 20% father away from the Sun- too cold carbon dioxide would build up
2.
Carbon baseda. Great bonding affinities
b. Allows for complex macro-molecules
3.
Terrestrial planeta. Crust thin/ thick and pliable enough to allow for plate tectonics
b. Recycling of minerals
c. Plate tectonics means the crust is sitting on an active core
d. Must retain enough heat for convection, i.e. keep the core liquid
e. Convection mixes the elements & shapes the continents
f. Active iron core is required to generate a protective magnetic field
g. Magnetic field has to be strong enough to withstand the solar winds
h. Must provide protection from radiation
4.
Oxygen atmospherea. Our oxygen/ nitrogen mix is good
b. Clear- allows for good viewing
c. Ours is <1% of planet’s diameter
d. Allows in the right kind of light for viewing
5.
Stable circular orbit6.
Large Moon (see also Gonzalez, G., “Wonderful Eclipses,”
Astronomy & Geophysics 40, no. 3 (1999): 3.18- 3.20) (J. Laskar et al., “Stabilization of the Earth’s Obliquity by the Moon,”
Nature 361 (1993): 615-17)
a. Our Moon is ¼ the size of Earth
b. Stabilizes the Earth’s axis of rotation
c. Gives our oceans a required tidal action
d. Just so happens that our Moon is 400x smaller than the Sun, which is 400x farther away
e. Both with a very circular shape
f. Allows for perfect solar eclipses
g. Confirmed Einstein’s prediction with the 1919 solar eclipse (gravity bends light) when scientists photographed the Stars behind it. We could have only made that discovery during a total solar eclipse.
h. Light spectrum
i. Observing & studying the Sun’s chromosphere is made possible
7.
Gas Giantsa. Protection from intruding cosmic debris
b. Great for observing & scientific discovery
8.
Sun- Spectral type G2 dwarf main sequence star- a. If it were smaller the habitable zone would shrink and any planets in that zone would be locked into a synchronous orbit (rotation = revolution) as our Moon is with us
b. Total number estimated in the Milky Way- 100 billion
c. Over 80% are low-mass red dwarfs (most likely lack a habitable zone)
d. 1-2% are massive short-lived blue giants
e. Only about 4% of the stars are early G-type, main-sequence stars like our Sun
f. 50% of those are in binary systems
g. Then we have to consider what % of those are in the Galactic Habitable Zone
9.
Location in the galaxy- Galactic Habitable Zonea. We are between spiral arms
b. Perfect for viewing
c. Not a lot of activity
d. Not too close to the violent and very active center
e. More radiation near the center
Neighbors
Not a good viewing platform from which to discover
Not so far away where the heavy elements are scarce
10.
Fine-tuninga. Laws of Nature
b. Laws apply here also apply anywhere
c. Constants that are independent of those laws
Summary:
Within the Galactic Habitable Zone
Within the Circumstellar Habitable Zone
Liquid water
Orbit a Spectral type G2 dwarf main sequence star
Protected by gas giants
Nearly circular orbit-
Oxygen rich
Correct mass
Large moon to stabilize the angle of rotation
Moderate rate of rotation
Terrestrial planet
Ratio of water to continents
Plate tectonic re-cycling
Magnetic field
Both plate tectonics and the magnetic field require the core have enough heat to keep it liquid. The convection currents mix the minerals before recycling and also produce the required magnetic field as it flows around the iron inner core.
The Earth’s orbit is slightly elliptical. When the Earth is closest to the Sun (perigee) the southern hemisphere is enjoying summer, i.e. the Earth’s axis of rotation has the southern hemisphere at a better angle (than the northern hemisphere) towards the Sun for absorbing its vital rays. The Earth has the bulk of its continents in the northern hemisphere. Water stores the heat and then transfers it around the globe.
The above list contains factors required for complex life, but life is not guaranteed to arise even if all factors are met. The fact that a large, stabilizing moon is required and ours just happens to provide us with a huge natural setting in which we can & have conducted a multitude of scientific experiments that have increased our knowledge base and confirmed scientific predictions, is just the tip of the iceberg when it comes to evidence to support their finding that habitability = measure-ability. Think about it. In the accepted age view of the solar system & Earth, with the Moon’s recession rate coupled with the Sun’s expansion rate, these perfect solar eclipses, along with the scientific discoveries that accompany them, will soon be gone (10 million years). The best place for viewing eclipses, is also the only place in the solar system with perfect solar eclipses, is also the only place with conscious observers and we, intelligent observers, just happened to arrive when the scenario was best for scientific discovery.
Earthquakes, even though very destructive, are a necessary byproduct of the required plate tectonic recycling. They also offer us a way to measure the density of the material between designated points via the sound waves produced by plate movement. Volcanoes offer a way to vent the internal pressure. Without vents the internal pressure would build uncontrolled, until the planet exploded. Plate tectonics also means that there is an active core. An active core like the Earth’s creates a protective electro-magnetic field. The size of the field is important- too small and the solar winds blow it away; too large and life is a no-no. Volcanoes are part of the mineral recycling process. Volcanic ash also covers the ground, not only providing rich soil for future generations but also in some cases creating a time vault that enables scientists to get an excellent view of the past. To support plate tectonics a crust that is thick enough to support oceans and continents is required, but it can’t be so thick that it doesn’t have subducting plates to recycle vital minerals.
The laws that govern nature are independent of the constants that control them. IOW fudge with the constants and even though the outcome is changed, the law still remains true. And that change will, in all likely-hood, prevent the conditions required for complex life.
Did we win the “cosmic lottery”? Or is intentional design, design with the purpose of having said design be understandable and ensuring beings exist that can grow to understand it, the better explanation?
See also:
The Privileged Planet