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My wife and I spent the last 12 days traveling in the New Mexico desert. The sky experience was spectacular, far better than anything Ohio has to offer.
Do not mistake yourself. If you want to visit one of our beautiful parks and state forests, you can get a pretty decent view of the true sky of southern Ohio. That's why I spend my observation time showing people the glory of the night from the new John Glenn Astronomical Park near the center of Hocking Hills National Park.
But New Mexico has something special because of its relative lack of polluting big cities and the variety of its climates. We've been hiking on the purest white gypsum sand dunes, in spectacular canyons and even through what we might almost call forests, if bush pines, big yuccas and cacti can be called trees. We also entered the underground depths of Carlsbad Caverns.
And the sky! I have never seen this shade of azure anywhere else. I have never seen such a pure sunset. And I have never seen so many stars disappear on the horizon.
The remote places of urban life offer the best of what nature offers us in abundance, both above and below the horizon – a real idea of the smallest details of our planet and its place in the cosmos.
I have been particularly impressed by the National Monument to Chaco Canyon, which, like many national parks and monuments, asks its guests to leave the scene at sunset. As we quickly obeyed the rules and rushed out of its raw beauty for one of the most beautiful sunsets I have ever seen, I remembered a story about the great John Dobson, inventor of the mount Dobsonian telescope and astronomer.
Dobson liked to load his bus down, "retired" with huge telescopes of his own creation. He has traveled from national park to national park showing people the real sky from the open sky watchtowers and car parks.
Such pleasures after dark were strictly contrary to the rules. As a result, he was often reprimanded by the rangers and sometimes expelled from the park.
At the Grand Canyon, a ranger sniffed, "Sir, the sky is not part of the park."
Dobson calmly replied, "Sir, the park is part of the sky."
And that, dear reader, is perfectly correct. One way to understand our place in the universe is to look closely at its microcosmic scale, an entity we commonly call "nature."
However, the part of nature under the horizon is only a small fragment of our larger natural world.
So do not stop there. After sunset, look over the horizon to find nature at its macrocosmic scale.
In other words, the best way to get an idea of the place of humanity in the universe is simply to go out and look at the sky in late fall. Of course, the universe is somewhat obscured by the glow of city lights. Why not take the afternoon drive to watch the sunset where the earth and sky meet and stay outside until the universe appears in all its splendor? Do not forget to bring binoculars or a small telescope for a better view.
As night falls, look with the binoculars you were born with, your two eyes. The western horizon glows from a strange convoluted band of silvery light. The summer Milky Way lies to the west, but do not worry. As the night progresses, the winter Milky Way will rise to the east.
You look at the distant stars of your own galaxy, the Milky Way, our cosmic neighborhood. The sun is just one of the 300 billion stars of the Milky Way, many of which are contained in the milky group you see. A simple game of binoculars is enough to blow up this group to make countless stars.
We know that this has been the case for a little over 400 years. All this time we were limited by what the human eye would allow us to see.
The Milky Way has the shape of an Olympic discus, wider in the center and glued to its edges. This cosmic discus has 100,000 light-years from one side to the other. (A light year equals approximately 6,000 billion kilometers.) Light a flashlight at one end and light takes 100,000 years to get to the other side.
Light a flashlight and point it to the moon. The light takes a hair more than one second to cover the distance. Compare a second to 100,000 years and you will begin to realize the enormous size of the Milky Way.
We live on the edge of the Milky Way. As we look in, the glow of innumerable stars and clouds of dust and gas obscures our vision of the greatest universe. To get an idea of the texture of the rest of the universe, we have to look away from the densest part of the Milky Way.
So, just after dark, look high at the constellation Andromeda, where only a thin veil of the Milky Way gets in the way. Far beyond the stars of the constellation, you'll see a cigar-shaped spot of light, called the Andromeda galaxy.
You look at the farthest thing that the human eye can see. His great distance became apparent just a century ago. During all the millennia that preceded, humans stared at this small, fuzzy area and did not realize that they had reached the limit of human vision.
Certainly, with the naked eye, the galaxy does not look like much, but it will fill the field of most binoculars. From our point of view of the Milky Way, Andromeda is partially inclined, which explains its oval shape.
At perhaps 200,000 light-years wide, the galaxy is twice the diameter of our Milky Way. Recent estimates of astronomers locate Andromeda at around 2.5 million years ago. It took 2.5 million years for the light you see to travel. In the huge gulf that separates the two could be placed end to end 15 galaxies of Andromeda and 30 milky ways.
After all my decades of observing the universe, a simple fact makes me lose the sense of oxygen: Andromeda is the great galaxy closest to our Milky Way.
The universe is composed of billions of galaxies such as Andromeda. If you passed a life, a hundred lives, to gaze at each visible galaxy telescope, you would see only a tiny fraction of the galaxies that make up the universe. Each of these galaxies would be much farther away than the faint layer of light called the Andromeda galaxy.
Look at these things once in your life. Look long enough and you will know the place of humanity in the universe.
Compared to the smallest star, you are a tiny and fragile creation. Your body is small, but your mind is measuring the universe as fast as you thought. Perhaps you will know that you had your eyes to see these things. You had the mind to share the immensity of the universe.
People worry a lot about the minutiae of their daily lives, they should also, I guess. They are more worried about the direction of our country and our world, and I do not want to minimize those concerns. In fact, I worry about all these things myself.
However, a lifetime of watching the sky has led to this now unshakable conclusion: once people see – once we see it – our miraculous place in the universe, the vast beauty and the cold efficiency of the cosmos, the smallness of our planet and our tenuous presence on it, the strength and fragility of this thing we call life, and the power and powerlessness we have on the the only planet we have ever called home, I know deep in my heart that they – and you – will do what is necessary. good thing.
Looking up the Andromeda galaxy is a good place to start this journey.
Tom Burns is the former director of the Perkins Observatory in Delaware.
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