— NASA (@NASA) April 18, 2016
The Water in Your Glass Might Be Older Than the Sun
By NICHOLAS ST. FLEUR APRIL 15, 2016
Earth is old. The sun is old. But do you know what may be even older than both? Water.
It’s a mystery how the world became awash in it. But one prevailing theory says that water originated on our planet from ice specks floating in a cosmic cloud before our sun was set ablaze, more than 4.6 billion years ago.
As much as half of all the water on Earth may have come from that interstellar gas according to astrophysicists’ calculations. That means the same liquid we drink and that fills the oceans may be millions of years older than the solar system itself.
The thinking goes that some of the ancient ice survived the solar system’s chaotic creation and came to Earth. To demonstrate that, researchers analyzed water molecules in oceans for indicators of their ancient past.
The clue comes in the form of something known as “heavy water.” Water, as you know, is made up of two hydrogen atoms and one oxygen atom. But some water molecules contain hydrogen’s chunky twin, deuterium. (It contains a neutron in its nucleus, whereas regular hydrogen does not.)