For most of my life I have been fascinated by the stars and in 1980 (early Middle School for me) I was moved by the PBS special by Carl Sagan called Cosmos. In the 13 part series I had my world view changed and although I was so young I realized there was something larger out there than just Earth. As an adult, I took up Astronomy and Cosmology as a hobby and although I learned much from reading, the true meaning of the Cosmos didn’t reveal itself until I bought my first real telescope and started practicing amateur astronomy for real.
With a telescope, you can view not only stars that reside within our own Milky Way galaxy but also star clusters, planets, asteroids, planetary nebulae and most importantly, other galaxies. There are no words that can describe the feeling you get when you view, with your own eyes, a galaxy that is millions of light years away. The light from the stars of those distant galaxies that is hitting your eyes left hundreds of millions of years ago. You are viewing what the Cosmos looked like before Dinosaurs became extinct! There are many ways I combat the stresses of daily life and one of the tools I employ is something I call ‘star therapy’. Nothing puts problems in perspective like getting my telescope out in the front yard and spending a couple hours looking at the wonders of the Cosmos. It is a hobby that has a steep learning curve but once mastered it can provide a lifetime of enjoyment.
Our Galaxy is about 100,000 light years wide and we occupy the space about 25,000 light years from the center of the galaxy – in other words, we are in the suburbs. We orbit around an ordinary star in a minor area of a galaxy in a known Universe that is comprised of billions of galaxies. Taking these facts into consideration we might conclude that we are not that special but yet we are. Let me explain how special our existence on this planet is but first we have to understand some history.
The Universe (as we know it) started around 15 billion years ago with the Big Bang. This is no longer a wild theory but accepted science once the Cosmic Microwave Background was discovered. Matter condensed to form stars and through fusion, the matter was converted to Hydrogen, Helium and the rest of the elements on the periodic table. Stars go through a life cycle – they are born when they reach sufficient mass that causes them to ‘turn on’ and start fusion, they continue to burn and fuse elements deep inside their cores and then die in various ways which disperses the elements to the rest of the Cosmos. This life cycle is called Stellar Evolution and provides the explanation of life on Earth because after several generations, stars eventually fuse Carbon, Nitrogen and Oxygen which are the building blocks of life as we know it. Most likely, our Sun is at least a 2nd generation star, formed from the remnants of several 1st generation stars’ death. The dust cloud of our star’s birth contained the Carbon, Nitrogen and Oxygen that enabled life to form on Earth.
The elements that make up life on Earth were formed inside stars. In other words, we are composed of star stuff! This is a profound truth that should not be taken lightly and it should guide us in our future endeavors. Evolution is not just confined to life on Earth but is a part of the entire Cosmos. We are the result of 15 billion years of evolution! If that doesn’t provide purpose in your life, then you don’t understand it. Think of it this way – It took the Cosmos 15 billion years to create ‘us’ and we should accept that mantle of responsibility to make sure we don’t squander that effort.
Are we the only planet in the entire Universe that has life? I don’t know but I would like to think that we are not. There are billions of stars in our own galaxy and there are most likely billions of galaxies so I doubt that we are the only planet within the ‘habitable zone’ around a start that is conducive for carbon based life. And that is taking the viewpoint that life can only exist in a carbon based form – we are biased to that form since we are that kind of life form. Only recently have we had the ability to discover planets around stars and in this short time we have discovered many stars that contain planets and dozens of those planets are within the ‘habitable zone’ that makes life as we know it possible to form. For a brief explanation on how we find these planets that orbit stars (they are called exoplanets), go to the following link.
Everyone should be an amateur Astronomer and realize the cosmological significance of our existence. Imagine how that would shape our Politics, Religion, Economics and Inter-National discourse. We are not Americans, Germans, Spanish or members of any other country; we are Earthlings and a member of the cosmic brotherhood. There is room for interpretation on how Religious beliefs play into this and I have reconciled my Christian beliefs with Cosmology but I’d like to think that a greater knowledge of our Cosmos would eliminate the Jihads and Crusades that squander life and threaten to squash 15 billion years of work that brought us to this point in time. How stupid would we be to exterminate each other with weapons of mass destruction and obviate 15 billion years of evolution? If we want to foster a culture of World Peace then we need to learn the lessons of Cosmic Evolution and realize our place in the Cosmos. Cosmology should be taught in High School and College to educate more of our youth about the Universe and help mold their Worldview as they grow to adulthood. We are very special because we live on a planet that is in the perfect orbit around a star that is perfectly sized to provide the perfect conditions for life to spring up and evolve. Now what do we do with this gift?