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You are looking at a corner of a rich star-forming region called the Lagoon Nebula. The entire nebula can be seen here. It is a large object, in the constellation Sagittarius, somewhat larger in apparent size than the full Moon, and barely visible to the naked eye under ideal conditions. It is about 5000 light-years away, in our own Milky Way Galaxy, about a sixth of the way toward the center.
Now let's take a trip backwards in our time machine to the time of Shakespeare and Galileo, 400 years ago, just as Galileo was making his first telescopic discoveries. What sort of world do we find ourselves living in?
A world created only a few thousand years ago, specifically for us. The Earth at its center. The stars just up there beyond the planets on an all-enclosing celestial sphere. Beyond -- the realm of God and the angels, who had little on their minds but us.
A Great Chain of Being reaches from the foot of God's throne down through hierarchies of angels to humans, then on through ordered ranks of animals, plants, and inorganic matter to the dregs of the cosmos at Earth's center. The human body is the microcosm, a little image of the larger universe, linked to the greater cosmos by a vast system of correspondences. Each of the seven holes in the head, for example, corresponds to one of the seven known heavenly bodies. Stars, planets, human life: All are engaged in a cosmic dance, orchestrated by the Creator.
From harmony, from heavenly harmony,An elaborate and beautiful construction that makes sense of every aspect of human life. (To appreciate it in its fullest, read E. M. W. Tillyard's classic little book, The Elizabethean World Picture.) Beautiful and satisfying, yes, but fragile. Precariously vulnerable to empirical refutation. "Take but degree away, untune that string/ And hark, what discord follow."
This universal frame began:
When nature underneath a heap
Of jarring atoms lay
And could not heave her head,
That tuneful voice was heard from high:
Arise, ye more than dead.
Then cold and hot and moist and dry
In order to their stations leap
And music's power obey.
From harmony, from heavenly harmony,
This universe began:
From harmony to harmony
Through all the compass of the notes it ran,
The diapason closing full in man.
Our task, as scientifically literate citizens of the 21st century, is to look at the image above squarely and unafraid, to see it for what it is, and for what it means about our place in the universe. We must embrace new correspondences -- physical and chemical -- in a new and disorienting kind of cosmic space and time. We must listen for a new kind of music, inaudible, humming at the very heart of creation, in every star, every nebula, every cell of our bodies. We must learn to think of ourselves as valuable, not because we are central or because we are the point of it all, but because in us the jarring atoms have contrived a way to bring the yawning, indifferent nebulas down to earth.