Water on Earth predates the solar system, and even the sun

la times ^ | 9-26-2014 | DEBORAH NETBURN

[Citizen Zed]

To find out, scientists turned to chemistry. Here on Earth, about one in every 3,000 molecules of water is made with a deuterium atom instead of a hydrogen atom.

A deuterium atom is similar to a hydrogen atom except that its nucleus contains a proton and a neutron, instead of a lone proton. (Both atoms also contain a single electron.) That makes deuterium twice as heavy as hydrogen, which is why water molecules made with deuterium atoms (HDO) are known as “heavy water.”

At the time that our sun was born, the ratio of deuterium to hydrogen throughout the universe was about 1 deuterium molecule to every 100,000 hydrogen molecules. But for water in the solar system, the proportion is significantly higher.

Water with a high deuterium content can only form under specific conditions. The environment needs to be very cold, and there needs to be enough energy to power the reaction that binds hydrogen, deuterium and oxygen. Over the past several decades, researchers have come up with two possible — and competing  — explanations of how this heavy water took up residence in our solar system.

The first is that it came from interstellar water ice that formed in the huge cloud of gas that gave birth to our sun and the solar system. Stellar nurseries can be found throughout the universe, and they are rich in both heavy water and regular water (H20), the researchers said.

The second possibility is that the violence and energy of star birth ripped apart that interstellar water, and its building blocks got reprocessed within the protoplanetary disk that would eventually coalesce into the planets and other heavenly bodies.

[John Valentine]

OK, but there is NOTHING in this article to indicate that anything is chiseled “in stone”. In fact, the article mentions that there are two (at least two) ideas that might explain the heavy/light water ratio of terrestrial water. This is really only of academic interest.

On the other hand, I am with you 100% when hypotheses (especially weak ones like man-made climate change/disruption/warming/cooling/ etc.) do become chiseled “in stone” and become the basis for misguided even disastrous public policy.

[Nervous Tick]

>> there is NOTHING in this article to indicate that anything is chiseled “in stone”.

Yeah, I sort of expanded the scope from a narrow answer to your question into a general-purpose rant. This particular article didn’t get that carried away.