Added to Catastrophism, because there's nonsense about Venus having once been a wet planet. Thanks MtnClimber.
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Posted on 03/23/2016 8:06:54 PM PDT by MtnClimber
Atmospheres, like love, often don't last forever. That's the lesson we astronomers are learning (well, at least, the atmosphere part), as we push outward with our telescopes into a galaxy rich with planets.
It's not an insignificant point, since the fate of atmospheres holds the key to science's most enduring question: Are we alone in the universe?
Last Monday, I spent the day at Penn State working with James Kasting on how planets can lose their atmospheres into space. Kasting is a great scientist who has spent much of his career exploring what allows a planet to become habitable. In astronomy, a planet is habitable if liquid water can exist on its surface. To answer his habitability questions, Kasting uses detailed models of planetary atmospheres that include the absorption of sunlight, the effect of ozone, the action of greenhouse gases and much more.
But, as Kasting will tell you, it's not just what happens inside the atmosphere that matters for keeping a planet safe for life.
What happens high up at the border with interplanetary space can also make the difference between a living or dead world.
(Excerpt) Read more at npr.org ...
This looks to be from NPR. Anyone see any propaganda content?
Dang, I thought this was an article about the GOPe.
Just one more thing to worry about.
He misses one other thing. What protects the Earth’s atmosphere is the Earth’s magnetic field, thanks to the spinning molten iron core. While Mars has a day similar to Earth’s, its core has solidified, thus its field is a mere remnant of what it likely was.
The resulting magnetosphere deflects much of the solar wind, which would otherwise ablate the atmosphere (as what likely happened with Mars).
Venus probably has a molten iron core, but does not rotate like Earth’s due to some tidal lock.
Don’t worry, you can probably get insurance for it.
Good observation. I did not know Mars core had solidified. In fact it is amazing that we have so much iron in our core. The atomic fusion in stars begins with hydrogen fusing into helium. The fusion in stars keeps going with many atomic numbers fusing until it gets up to iron. When this point hits the gravity cannot hold the expansion and a star explodes into supernovae. So our earth and the iron core is likely from the debris of past stars.
Mars they think billions of years ago had a much thicker atmosphere. They say it was destroyed by cosmic radiation when the planet lost its magnetic field and could no longer repel the charged particles. It lost its magnetic field when the core cooled down to the point where it could no longer generate a field.
They know this because magnetic minerals in the ancient bedrock are aligned in one direction while similar minerals in much younger lava rock are not. Both sets of rock were once molten and so minerals were free to align to a magnetic field, if one were present.
Ummmm, yes!
They create an impression of instability and uncertainty for the future of earth's atmosphere by the description of the variability ( over billions of years ) of the atmospheres of other planets under much different conditions.
They include the magic words, "potent greenhouse gasses", so that we may make the connection. It's all, "up in the air" ... ha ha!
“He misses one other thing.”
That NPR for you. Of course they are perfectly believable when it comes to “Global Warming”! /sarc
Added to Catastrophism, because there's nonsense about Venus having once been a wet planet. Thanks MtnClimber.
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Thanks MtnClimber.
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