DEJA VU

"Memory is like riding a trail at night with a lighted torch.
The torch casts its light only so far, and beyond that is darkness."

----------- Old Lakota Sioux Saying

Earlier this year, I discussed a published report that scientists have asserted the Earth's water was delivered to it by ice-infused asteroids and/or meteorites.* This conclusion was based upon comparisons of the Deuterium-Hydrogen (D/H) ratios of Earth water with water found in rocks from outer space.

Now, a new published report suggests that this water origin conclusion may not be correct, and that no one yet knows how water got here.** According to this report, there are problems with the prior D/H ratio analysis. Most of Earth's water is deep underground and has a different composition from ocean water. In particular, deep water has a different D/H ratio than the seawater ratio previously used to compare with asteroid and meteorite water.

Further, D/H ratios may not be reliable because Deuterium tends to become more prevalent at lower temperature, and computations are variable with distance from the sun making the ratios of questionable value in locating the origin of a water-bearing comet. Alternative ratios, such as nitrogen and oxygen isotopes have been suggested, but such measurements apparently require development of new instruments.

According to the report, no one knows how much water is inside the Earth. Estimates vary from 1.5 times to 11 times the amount of ocean water. Scientists are studying a series of underground lakes located hundreds of feet below Wind Cave National Park in the Black Hills, South Dakota. Wind Cave comprises at least 170 miles of honey-combed tunnels and is said to be the third largest cavern in the world. The lakes pop up in some of these tunnels and form the top of the Madison Aquifer, a valuable drinking water resource. The Lakota believed that their ancient gods delivered their ancestors from Wind Cave to the surface of the Black Hills.

As if figuring out where Earth water came from was not challenging, another report states that several moons of Jupiter and Saturn contain underground oceans of water, not to mention the possibilities on Mars.***

Is looking for a scientific explanation for the origin of water on Earth or anywhere else like looking for love in all the wrong places? To paraphrase the Lakota, "Looking for the origin of Earth's water is like riding a trail at night with a lighted torch. The torch casts its light only so far, and beyond that is darkness."

____________________________________________

* "Who Cares", May 27, 2015

** Crockett,"Struggle To Find Origin Of
Earth's Water",Science News,September 5,
2015, p.8

*** Crockett,"Ocean Envelopes All Of
Enceladus", Science News, October 17,
2015, p.8