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-   -   Vision on Venus (http://www.physicsforums.com/showthread.php?t=3354)

Andre Jun27-03 01:25 PM

vision on Venus
 
There may have been other threads, wondering about the mystery of Venus. Or to sum up:

http://solarsystem.nasa.gov/feature...enus/venus.html
Quote:

The atmosphere consists mainly of carbon dioxide (the same gas that produces fizzy sodas), droplets of sulfuric acid, and virtually no water vapor - not a great place for people or plants! In addition, the thick atmosphere allows the Sun's heat in but does not allow it to escape, resulting in surface temperatures over 450 °C, hotter than the surface of the planet Mercury, which is closest to the Sun. The high density of the atmosphere results in a surface pressure 90 times that of Earth, which is why probes that have landed on Venus have only survived several hours before being crushed by the incredible pressure. In the upper layers, the clouds move faster than hurricane- force winds on Earth.

Venus sluggishly rotates on its axis once every 243 Earth days, while it orbits the Sun every 225 days - its day is longer than its year! Besides that, Venus rotates retrograde, or "backwards," spinning in the opposite direction of its orbit around the Sun. From its surface, the Sun would seem to rise in the west and set in the east.

Earth and Venus are similar in density and chemical compositions, and both have relatively young surfaces, with Venus appearing to have been completely resurfaced 300 to 500 million years ago.

The surface of Venus is covered by about 20 percent lowland plains, 70 percent rolling uplands, and 10 percent highlands. Volcanism, impacts, and deformation of the crust have shaped the surface.
There seems to be some explaning to do here for the boldface. We have some tidal - gravity lock mechanism that may have caused that rotation stop, but we may need a asteroid impact to slow down the planet first. There may have been a runaway greenhouse gas mechanism for the extreme temperature but what can cause a complete resurfacing of the planet? Acne redecorating limited? :smile:

I figured out an idea that may logically account for all four of those enigmatic features. But it requires some thinking out of the box. Anybody ready for debunking me?

neutroncount Jun27-03 01:36 PM

Very active volcanos could resurface most of the surface if there were enough of them and they were given enough time. I do know Venus has active volcanos.

I, Brian Jun27-03 03:53 PM

Accretion theory itself is still on a fractional explanation of planetary formation. Until there's a more definite answer of how Venus formed - and, not least, how it developed from that - then those mysteries will remain as they have done since revealed.

I'm sure I just saw on Ceefax possible plans by the European Space Agency to launch a lander to Venus late 2005. A story to watch for.

Andre Jun28-03 03:20 PM

Yes that ESA trip could be interesting. I hope I could make a few suggestions for research. Now about my idea. Suppose that Venus just looked similar to Earth or Mars initially billions of years ago, albeit a bit hotter due to the proximity of the sun, but with a normal spin rate, initially of about 13,5 hours, according to the empirical equation.

Now other than a most unlikely asteroid collision or a thermal greenhouse runaway, I may have stumbled upon a single mechanism that accounts for the resurfacing, the high temperature, the dense CO2 atmosphere and the rotation stop.

More tomorrow.

Andre Jun29-03 08:24 AM

Suppose that Venus has been like the other inner planets, the Earth and Mars, rotating likewise, in the same direction of the orbit, with much similar features.

According to the conventional ideas, the cores of the planets generate heat due to compression, possible nuclear decay processes, Not much difference between Venus, Earth and Mars yet.

Venus was probably rotating normally a few billion years ago, likely the spin axis also being sa bit tilted like the Earth. Also, it has an equatorial bulge and with those properties, also a precession movement, just like Earth, the Precession of the Equinoxes. This precession is supposed to be caused by differential gravity pull of the sun and moon on the closest and farther part of the equatorial bulge. It caused the spin axis of the planet to slowly make a cone like movement

Again the planets are still much the same. Perhaps two things slightly different for Venus, Again, it hass less mass than the Earth and because of that is has compressed less, therefore it may have a slightly bigger core With less compression and perhaps less heavy mass from radiactive elements the core did not heat up that much and Venus may have cooled faster than the Earth.

The core of the earth consist of a liquid outer core and a solid inner core. It is solid despite the high temperature due to the immense pressure it is subjected to. In the core there is a equilibrium between two opposing tendencies, the high temperature tries to liquefy the core and the high pressure tries to solidify the core. Where pressure is higher(inner core) the core is solid and where temperature is higher in relation to the pressure (outer core) it is liquid. But as the earth cools the temperature decreases and hence the solid inner core expands at the cost of the outer core. Since cooling is much faster for the smaller and lighter Venus it may be that the same process took place million of years ago.

These are the basic elements we need. So, what made Venus to the counter rotating Dante’s inferno that it is now?

Deeviant Mar4-04 02:46 PM

Quote:

Originally posted by Andre
Suppose that Venus has been like the other inner planets, the Earth and Mars, rotating likewise, in the same direction of the orbit, with much similar features.

According to the conventional ideas, the cores of the planets generate heat due to compression, possible nuclear decay processes, Not much difference between Venus, Earth and Mars yet.

Venus was probably rotating normally a few billion years ago, likely the spin axis also being sa bit tilted like the Earth. Also, it has an equatorial bulge and with those properties, also a precession movement, just like Earth, the Precession of the Equinoxes. This precession is supposed to be caused by differential gravity pull of the sun and moon on the closest and farther part of the equatorial bulge. It caused the spin axis of the planet to slowly make a cone like movement

Again the planets are still much the same. Perhaps two things slightly different for Venus, Again, it hass less mass than the Earth and because of that is has compressed less, therefore it may have a slightly bigger core With less compression and perhaps less heavy mass from radiactive elements the core did not heat up that much and Venus may have cooled faster than the Earth.

The core of the earth consist of a liquid outer core and a solid inner core. It is solid despite the high temperature due to the immense pressure it is subjected to. In the core there is a equilibrium between two opposing tendencies, the high temperature tries to liquefy the core and the high pressure tries to solidify the core. Where pressure is higher(inner core) the core is solid and where temperature is higher in relation to the pressure (outer core) it is liquid. But as the earth cools the temperature decreases and hence the solid inner core expands at the cost of the outer core. Since cooling is much faster for the smaller and lighter Venus it may be that the same process took place million of years ago.

These are the basic elements we need. So, what made Venus to the counter rotating Dante’s inferno that it is now?

The easiest answer: The sun.

Andre Sep29-05 01:26 PM

I don't think so.

Then why isn't Mercury hotter and why has Venus been much hotter a billion years ago.

Cleaned up the files and had forgot about this one. A smoking gun for crying out loud.

http://www.lpi.usra.edu/meetings/lpsc97/pdf/1343.PDF

Fits beautifully, 100%, into the hot brake hypothesis and debunks the radiogenic heat hypothesis at the same rate which should have resulted in a large excess of 40Ar.

However, trespassers will be prosecuted and I will never get past the not-invented-here spirit. So here is the almost finished manuscript. Go ahead, Get this in, finish it, put your name on it and publish it.


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