Ever ancient, ever new

Door honoring Pope Benedict
in St. Thomas of Villanova church
in Castel Gandolfo.

I just sent off a draft of an essay about water, prompted by reading a paper about "primordial" water, water trapped in the rocks for 2 billion years or more.  Where does the water on earth come from?  For that matter, where does the water in the universe come from?  In one sense, it's incredibly old. The hydrogen atoms, the two H's in H₂O, were made when the universe was 1 second old.  One second. My mind still can't quite take it in. It will take almost another half billion years for oxygen to make an appearance, three times that for water to begin to form.  The earth's water is almost as old as the solar system itself, 4.5 billion years old.

Detail.  Note equations! You can see the tail end of a
double helix at the upper left. 

But individual water molecules don't last long, the average lifetime is on the order of milliseconds. So no water molecule is old, those particular two hydrogens and that oxygen might stay together for a few milliseconds, then exchange a hydrogen with another water, an eternal dance, hand over hand.  The atoms are ancient, the molecules — brand new.

The famous line from Augustine's Confessions kept running through my head, "Late have I loved you, O Beauty ever ancient, ever new, late have I loved you!"  Water, ever ancient, ever new.