As pointed out in the article, ‘Fine Tuning of the Universe’, we conclude that the Universe is Fine tuned to permit Life on earth. Additional proof of the Fine Tuning comes from the fact that the Universe is not only Fine Tuned to permit complex life, but infact our place in the Universe is also designed for Scientific Discovery.
Recently a book published by the name of ‘The Privileged Planet: How Our Place in the Cosmos is Designed for Discovery ‘, the authors, Guillermo Gonzalez and and Jay Richards, have observed that The same narrow circumstances that allow us to exist also provide us with the best overall setting for making scientific discoveries. Those things that make the planet habitable also make that planet the best place for making scientific discoveries.
Some of the evidences for these claims are as follows
On October the 24th 1995, a rare natural phenomenon, a complete solar eclipse was observed from India. For 51 unforgettable seconds astrophysicist Guillermo Gonzalez and thousands of others observed in wonder at this rare historical event.
Guillermo Gonzalez would later reflect on both the mysterious beauty he had witnessed in the sky and the factors that made it possible.
The requirements of producing a total eclipse of the sun are an illuminous body, in our case the sun, an eclipsing body, our case the moon, and an observable platform, in our case, the surface of the earth. And all have to be in the straight in space. The apparent size of the moon in the sky has to be the same as the apparent size of the sun in the sky. The sun is 400 times bigger than moon but its 400 times further away. So there is this co-incidence that people have noted for centuries but they say it’s a co-incidence and try to avoid it.
As Guillermo Gonzalez observed this rare alignment of the sun, the moon and the earth, he recognised the importance of the celestial bodies to the existence of complex lives on our planet. The gravitational pull exerted by our moon, for example, is strong enough to regulate the earth’s climate by stabilizing its tilt and helping to circulate its warm and cold water of its oceans. While our plant’s distance from the sun permits both liquid water and an oxygen rich atmosphere.
You have to have the right distance of the observer’s home planet from its host star and you have to have a large moon and so there is this very strong overlap between the requirement for producing eclipses and the requirement for habitability in a planet that can support life. In 1999 Guillermo Gonzalez described this relationship between our survival and our ability to observe solar eclipses in the journal ‘Astronomy and Geo-Physics”.
In the summer of 1999 Guillermo Gonzalez and Jay Richards initiated a process of joint research. He began his study by considering a characteristic of solar eclipses little known outside the scientific community. These striking events are not only compelling to observe, they also open a port onto the physics and chemistry of the entire universe.
Guillermo Gonzalez observes “really you can think of the eclipse as a giant natural experiment – a setup that allows us to observe a part of the sign that’s critical towards understanding how its light is produced in its atmosphere”.
The fact that the earth is going around the sun and the moon is around the earth and the sizes and the distances between the sun and the moon and the earth are just so to give you a perfect solar eclipse is a wondrous thing because it allows us to measure the constituents of the upper layer of the sun’s atmosphere.
During a solar eclipse the moon fits so perfectly over the sun that it shields its blinding light providing astronomers with a view of the star’s atmosphere otherwise impossible to experience. At the moment of totality, the pinkish arc of the chromosphere (the atmosphere’s innermost layer) becomes visible and with it a rainbow like band called the flash spectrum appears, when the sun is viewed through a prism. The eclipse of the 1870 let to an understanding of the structure of the sun’s chromosphere and the discovery of helium, the second most abundant element in the universe.
Guillermo Gonzalez says “The spectrum is probably the single greatest source of information about our star and it was during a couple of historic eclipses in the 19th century that astronomers figured out how the spectrum of the sun is produced and they were only able to figure it out because of the particular circumstances during a total eclipse”
These circumstances are both precise and crucial. If our moon was slightly larger, it would partially block our view of the chromosphere and diminish its spectrum light. A small moon would allow too much light from the sun, destroying our view of the solar atmosphere and the flash spectrum.
So you have to have a nearly perfect match between the sun and the moon so you don’t hide the chromosome and that insight afforded by eclipses in the 19th century, is what finally permitted the astronomers to figure out how the spectral distant stars are produced. Really that opened up star astrophysics and allows us to understand how other stars work because distant stars are after all other suns.
The relationship between eclipses and scientific discovery was also revealed in the spring of 1990. On may the 29th research teams headed by British astronomer Arthur Eddington photographed the sun and the adjacent star cluster during the darkness of totality. Later analysis of the pictures verified that the sun’s gravity bent light from distant stars coming towards the earth at the angle Albert Einstein had predicted. Einstein’s theory of relativity, idea that revolutionised our idea of the universe, had been confirmed, during a total solar eclipse.
Guillermo Gonzalez comments “And that experiment was only possible because the stars become visible during a total eclipse. They are very important in the history of science and the best place in the entire solar system to view solar eclipses is from the surface of the earth. I have actually calculated the circumstances for eclipses for all the other planets and all the other moons, about 65 of them, the major moons, and its amazing co-incidence that the one place that has observers is the one place that has the best eclipses”
Here we recognise a fascinating connection between the factors necessary for complex life and scientific observation.
The atmosphere of the earth. Its striking when you see pictures of the earth, you see this very thin layer of the atmosphere that sustains all life we know and so we need certain mix of elements in order to support a complex biosphere like ours. Not just any atmosphere would do.
Our appreciation of the Earth’s atmosphere has increased significantly during the last 40 years. As exploratory spacecraft observed the solar system.
These missions have confirmed that within the sun’s family of more than 70 planets, the earth is one of seven bodies enveloped by a thick canopy of gas. Yet among these seven, only the Earth’s atmosphere can sustain complex life and only the earth’s atmosphere is transparent.
Its an atmosphere made up of mainly oxygen and nitrogen with very little carbon dioxide and very little other carbon compounds or atoms that gives you a transparent atmosphere. If we have too much of carbon in the atmosphere, we get organic hazes in the atmosphere. The dense shroud of gas that blankets Saturn’s largest moon resembles the atmosphere surrounding Neptune, Uranus, Saturn, Jupiter and Venus. None of these alien worlds know the stars or even offers a clear view of the sun.
If you are transported to any such planets, the hazy vision would not be much of an issue, because you would be dead. But that’s basically the point. If the conditions that are required for habitability and scientific discovery appear in the same place, then you are going to get conditions like you get on earth. An atmosphere that sustains complex life, like ourselves and also enables scientific discovery of the Universe around us.
As the earth moves through space, it is bombarded by radiation from throughout the universe. This radiation is emitted by the sun and other celestial objects. It reaches our planet in wavelengths described as Gamma, X-ray, Ultraviolet, Visible, Infrared, microwave, and radio. Together they comprise the electromagnetic spectrum. Almost all of these wavelengths are invisible to the eye and are either lethal or useless to organic life. Yet within this spectrum of frequencies a thin sliver of radiation proves essential to plants, animals and human beings.
In other words a very narrow part of the electromagnetic spectrum thats going to be useful for living processes like photosynthesis. Its not that life could have evolved to use gamma radiation or x-ray radiation or something like that. There’s just a narrow part of the spectrum that would be useful for life processes. Well as it turns out, that’s also the same narrow part of the spectrum that’s is the most informative about the various structures that we discover in the universe around us.
These specific frequencies that enable plants to manufacture food and astronomers to observe the cosmos represent less than one trillionth of a trillionth of the universe’s range of natural electromagnetic emissions. Fortunately it is the type of light our sun produces in abundance and that most easily penetrates the filtering shield of our atmosphere to reach the surface of the earth.
A remarkable co-incidence that the kind of atmosphere that supports complex life like ourselves does not preclude that life from observing the distant universe.
Earth’s specific location between the Milky Way galaxy provides more evidence of a correlation between life and discovery.
Just as our location in the solar system is optimized for hospitability, so is our location in the Galaxy. We inhabit a spiral galaxy, which means its highly flattened, and has a spherical boulder in the centre and has spiral arms. And we live in about half way between the centre of the galaxy and the edge.
Galactic centre is the most dangerous. High density of stars, black hole, exploding stars, deadly radiation would make complex life virtually impossible. Outer edge poses other challenges. We live on a planet made of iron, magnesium and silicon and oxygen. In the outer edges, the abundances of these elements are lower. There are not enough heavy elements to build earth size planet that can support life.
In the middle, there is a Galactic Habitable zone, where complex life is possible within the Milky Way. Even large areas within the Galactic Habitable zone are less hospitable to complex life. We don’t want to be close to the spiral arm. We want to be outside the spiral arm at about the right region of the galaxy. This is precisely where the earth is located, in a relatively safe and uncrowded region. Location is everything, and so we occupy that special place in the galaxy where habitability is optimized.
The earth is also located in the best setting in our galaxy for astronomical research. As it turns out, our position in the Universe is not only critical for life, but its also surprisingly important for making scientific discoveries. We’re located in the middle of the galaxy, a highly flattened galaxy, between spiral arms and very low dust extinction. While we are in the plain of the galaxy, that does not obscure a large part of the sky, where you can have very clear views.
For more than a century, this nearly ideal platform of observation, has enabled the astronomers to study, the structure of the milky way. Looking towards the constellation, Sagittarius, on a clear night for example, we see that the stars in our galaxy are not uniformly distributed, across the sky. Instead they appear as a part of a concentrated band, a flattened disc of stars, dust and gas, one thousand light years of diameter.
The Milky Way band in a night sky is us looking into the edge of the galaxy. If we are living in the centre of the galaxy, things would look much more spherically distributed and so, It will be very hard to distinguish things that are inside the galaxy, form things that are outside.
And its also very much dusty, much dustier towards the galactic centre that there is in our region and so the views of the distant galaxies will be much more difficult to obtain, and will be much more compromised.
Similar problems will exist for astronomers working on a planet located within any of the galaxy’s spiral arms. Here denser concentrations of dust clouds and gas illuminated by stars would make it difficult to determine the shape of the Milky Way or to distinguish the stars in our galaxy from the rest of the universe.
On the surface of the earth we are really in an optimal position for seeing both the nearby structure of the milky way galaxy as well as seeing the distant cosmos as a whole. So once again we see that the best location for habitability and for producing a habitable planet is also the best overall position for scientific discovery and in this case, it’s the galactic scale.
So we conclude that Universe is not only Fine Tuned to permit complex life, but infact our place in the Universe is also designed for Scientific Discovery. For more details refer to the book The Privileged Planet: How Our Place in the Cosmos is Designed for Discovery