Water and the lunar surface

[Woggles]

I was read in Science 101 forum today "Beneath the Surface, the Moon Is Dry as a Bone" the link to the article http://news.sciencemag.org/sciencenow/2 ... n-is-.html .

In this article, the reporter is quoted " Scientists have been arguing for decades about whether the moon contains significant quantities of water. Theoretically, it should because the moon was once part of Earth. (It was created by a catastrophic collision between our planet and a Mars-size body over 4 billion years ago.)"

I was wondering if this changes the theory that the moon was form this way?

 

[MeteorWayne]

Actually, the prevailing theory was that all the water was destroyed during the catastrophic collision, and anything there has been deposited since or created by the solar wind.

 

[Woggles]

Thank MW. I didn’t know that part. So in thinking about this, would the earth, at that time, have much more water then now and some of it would have been destroyed in the collision?

 

[MeteorWayne]

Yes, a large part (or all) of the earth's water would have been destroyed as well. Most of the water here is thought to have been delivered by comets later, though the evidence is not yet conclusive one way or the other. We are still learning

 

[Woggles]

Actually, the prevailing theory was that all the water was destroyed during the catastrophic collision, and anything there has been deposited since or created by the solar wind.

So the finding of no water beneath the surface of moon would validate the prevailing theory. Interesting!!!

 

[StarRider1701]

Actually, the prevailing theory was that all the water was destroyed during the catastrophic collision, and anything there has been deposited since or created by the solar wind.

Interesting. I've never been a big fan of the "catastrophic collision" theory and I think we are now on our way to proving it wrong. There are parts of that theory that have never made sense to me. I've always though the moon may have started life as the moon of another body here in this solar system and found its way here later in time. I think the amount of water in the lunar regolith may be an indicator of this as well as if we find water deeper beneath the surface.

 

[neilsox]

Assuming the center of the moon is cooler than 1000 degrees k (likely) liquid water could average more than 1% of the total mass of the moon, most of it far below the surface. Earth's water is nearly all within 50 miles of the surface, due to the hot interior? Neil

 

[Woggles]

Assuming the center of the moon is cooler than 1000 degrees k (likely) liquid water could average more than 1% of the total mass of the moon, most of it far below the surface. Earth's water is nearly all within 50 miles of the surface, due to the hot interior? Neil

Hi Neil

I guess we really won't know on till there a deep drilling for core samples. I was wondering is there any other way to determine if water is liquid, as in pools or lakes. Maybe seismic?

 

[neilsox]

My guess is water resources more than 5 kilometers below the surface of Earth are subject to reasonable doubt. Yes extensive seismology of the moon should allow us to make educated guesses about pools and streams of liquid water all the way to the center, but reasonable doubt will likely remain forever unless we drill holes more than 1000 kilometers deep. That may be possible, but will be incredible costly. The deep rock pressure and temperature of the moon are likely much less than for earth. Neil

 

[neilsox]

Most of the surface of the moon to a depth of about one centimeter gets heated to 100 degrees c for about 200 hours each month. This is much hotter than the boiling point of water in a vacuum, so we would expect to find an average of a few parts per billion = almost none of water one centimeter below the surface except for locations almost always shaded from sunlight and very recent meteor hits. There is some evidence of rare and small locations on the moon where water is coming up from the depths, so these, if any, likely have damp regolith = soil. Neil

 

[Woggles]

Thanks Neil for the info. Don't really find much to read about this anywhere.