This is the Hubble Deep Field photograph. It shows an area of the sky equivalent in size to a tennis ball held 100 meters away... 2.5 minutes of arc. That is a tiny sliver of rather nondescript sky in the constellation Ursa Major, but this photo shows thousands of galaxies, each containing hundreds of billions of stars, and all at a distance of many thousands of light years away.
If this doesn't absolutely blow you mind, well...
I don't know what will.
When one really begins to ponder the significance of this photo, it is hard to overstate how impressive and grand our idea of our universe becomes. This photo represents 1/500,000 (one part in five hundred thousand) of the total sky as viewed from earth... so multiply all those figures I listed above for the number of galaxies and stars in this photograph alone by a 500,000 and you will approach the number of galaxies and stars in our observable universe... a conservative estimate at that, since this photo was purposely taken in one of the emptiest (in terms of visible light) patches of night sky that they could find.
Look at all of that... all of that matter, all of that energy, all of that space. That is a tiny fraction of the observable universe, and we have every reason to think that the observable universe (from Earth, that is) is itself just a tiny fragment of the universe as a whole.
For further perspective, gaze at this photo, taken by Voyager 1 at a distance of 6 billion kilometers from earth. That tiny, blue pixel in the farthest right ray of sunlight contains everything that we are- literally, our whole world. That tiny speck, easy to overlook and insignificant, represents the entirety of yours and my existence.
The next time that you begin to entertain delusions of your own grandeur, remember that you are an absurd bag of molecular carbon- a mere chemical reaction, writ however large- resting on a tiny ball of rock and metal which can barely be seen from the extraordinarily close (astronomically speaking) vantage point of only a few billion kilometers.
Wars have been fought by other bags of carbon over which one of them shall control a tiny fragment of this tiny fragment but for only a tiny fragment of time.
It certainly gives one pause to stop and think, if nothing else...
We live in a philosophically absurd world, and the only sense that we can make out of it comes from observation and experiment... in other words, from science. And yet, a vast number of people hold the idea that somehow their life is special- granted some cosmic meaning by an invisible deity. They hold the idea that our world is somehow special for the same reason. They would do away with science and leave in its stead the clumsy and repressive methods of faith and superstition.
If we are ever to make it off of this pale, blue dot and explore the universe beyond or rather puny horizons, we must first cast off the shackles of religion and superstitious belief. We must embrace the truth- and that means simultaneously embracing the knowledge that we are but an almost infinitesimally small part of this universe, neither necessary for its existence nor special among its many quintillions of molecular collections.
So there you have it... the astronomically large and the infinitesimally small. The entirety of the universe is the former, and we humans and everything we create are the latter.
There is a kind of grandeur in this view of the universe... a sense of awe, wonder, and beauty that is unparalleled in my life. It astonishes me time and again how people can willingly turn away from this compelling and magnificent view of existence and instead opt for the close-minded, dogmatic views of religious superstitions. I am told all the time that since I am an atheist, my life must be drab and bland. My life, the theists tell me, must not have any wonderment in it at all, since I am a godless disciple of science.
When I hear things like that, I chuckle softly to myself. For I have in my mind at all times these beautiful and consequential images, courtesy of NASA (and, the latter, Carl Sagan himself). And I know that no religion, no deity, could ever come close to the awe-inspiring and wonderful universe that is reality.