Venus: what went wrong?

[DDE]

So, a theory pursued by guys and gals at Goddard is that Venus's predicament is a relatively recent condition (~715 mln years) and it was preceded by distinctly Earthlike conditions. This aligns well with the fact that Venus's surface, all of Venus's surface, is about that old, indicating a global resurfacing far in excess of anything observed on Earth.

What could cause such a global apocalypse? Discuss.

Spoiler

I'm not saying it was aliens, but...

 

Edited September 23, 2019 by DDE

[Barzon]

can you post the source?

[magnemoe]

Venus has an very slow rotation as in rotate backward. Earth, Mars, Jupiter, Saturn and Ceres is much closer in rotation speed, Mercury has loads of tidal effects from sun. 
My guess it got unlucky, we got the moon, on Venus the hit was a bit different and probably larger. 
Kind of doubt it was earth like, the low rotation speed probably caused issues. 

No plate tectonic, but you get lots of major lava flows like the Siberian traps, this was probably much more violent some billion years ago. 
Note you don't want something some magnitudes worse than all the super volcanos popping at once at an regular basis then you are scary close the the sun. 
 

[AngrybobH]

1 hour ago, magnemoe said:

My guess it got unlucky, we got the moon, on Venus the hit was a bit different and probably larger. 

This is my guess as well.

[pmborg]

What make planet Venus hot because of his rotation period, 

Biggest factors that contribute for the surface temperature in scale:

1. Gravity Pressure (for super earth's and gas giants)
2. Distance from Star (in relation to star size)
3. rotation period - Time to allow the planet to get the max temperature per day
4. atmosphere density and composition

For example the

• moon have a rotation period of 27.3 days : Min-Temp:100 K - Max-Temp: 390 K
• earth today we have a rotation period of 23h 56m 4.100s : Min-Temp:184 K - Max-Temp: 330 K ()

In recent earth ancient history the planet was colder due it's rotation:

• Thanks to our moon collision with proto-earth the day lasted only 4 hours  (4,533 million years ago)
• 3.5 billion years ago, happened when the day lasted 12 hours.
• The emergence of photosynthesis, 2.5 billion years ago, happened when the day lasted 18 hours.
• 1.7 billion years ago the day was 21 hours long and the eukaryotic cells emerged.
• The multi-cellular life began when the day lasted 23 hours, 1.2 billion years ago

In this case, the minimum and the max are directly related with the rotation period, because the Gravity Pressure is similar and the Distance from Star don't make such a huge difference in this case from Venus to earth should be about between 25 and 30 deg Celsius.

what went wrong?

Didn't had the bad fortune of another planet collision in the begging of its formation, the bad "luck" was for proto-earth and that lead to our current avg temperature, 4,533 million years later.

If proto-earth didn't had the Theia planet collision 4,533 million years ago, earth today it would have the similar avg temperature of Venus today.

 

 

Edited September 23, 2019 by pmborg

[ThatGuyWithALongUsername]

It's kind of interesting that all 3 rocky planets in our solar systems' optimistic habitable zone (Venus is kinda on the edge, but whatever) are believed to have been earthlike at one point, but different things led to only one of them remaining that way. It's both good news (earthlike conditions are common) and bad news (but can only be sustained under apparently narrow circumstances- I mean, these are planets, there are a LOT of variables, things will turn out differently) for the search for habitable exoplanets.

 

Anyway, clearly what happened here is the Venusians didn't heed their scientists' warnings about climate change (joking, of course... though seriously people, come on).

EDIT: and, uhhh... the resurfacing event was caused by... uh... didn't think this through I guess.

Edited September 23, 2019 by ThatGuyWithALongUsername

[Wjolcz]

2 hours ago, magnemoe said:

My guess it got unlucky, we got the moon, on Venus the hit was a bit different and probably larger. 
Kind of doubt it was earth like, the low rotation speed probably caused issues. 

What interests me the most is how often such collisons happen in other solar systems. If Venus got smacked too hard, Mars probably got a similar treatment and Earth got hit just right to get a moon big enough to help stabilize and enrich it with heavier metals then the odds of having such binary planet-moon systems are much higher, thus complex life is much more likely in the universe.

[kerbiloid]

Wrong went with Earth, Venus is proper.

P.S.
Venus couldn't be Earth-like at least because she doesn't have continental platforms.
It hasn't been affected by a close interaction with another major body (the proto-Moon), so it wasn't rotated and partially melted.
So, its core extraction happened slower, smoother, without continents and other drama.
So, it keeps the original rotation, its light elements have been slowly exhausted from the minerals, and formed the atmosphere.
It's close to the Sun, so it was too hot to condense water before it has been splitted and dissipated.

The Mars presumably has been hit by a Pluto-sized body (a half of it is one big crater). So, it's fast, too.

Edited September 23, 2019 by kerbiloid

[magnemoe]

6 hours ago, Wjolcz said:

What interests me the most is how often such collisons happen in other solar systems. If Venus got smacked too hard, Mars probably got a similar treatment and Earth got hit just right to get a moon big enough to help stabilize and enrich it with heavier metals then the odds of having such binary planet-moon systems are much higher, thus complex life is much more likely in the universe.

Guess its lots of gigant impacts, why is Mercury an iron core with an thin top layer. Uranus with its tilt. Earth's moon, Venus rotation. 
Some recent study indicates Jupiter ate something Neptun sized and still show signs of it.

Planetary formation is pretty violent as in PEGI age rating would be geological 
Think of it as an battle royale there you eat your enemies. 

Edited September 24, 2019 by magnemoe

[magnemoe]

6 hours ago, kerbiloid said:

Wrong went with Earth, Venus is proper.

P.S.
Venus couldn't be Earth-like at least because she doesn't have continental platforms.
It hasn't been affected by a close interaction with another major body (the proto-Moon), so it wasn't rotated and partially melted.
So, its core extraction happened slower, smoother, without continents and other drama.
So, it keeps the original rotation, its light elements have been slowly exhausted from the minerals, and formed the atmosphere.
It's close to the Sun, so it was too hot to condense water before it has been splitted and dissipated.

The Mars presumably has been hit by a Pluto-sized body (a half of it is one big crater). So, it's fast, too.

Well if true you solved the Fermi paradox. 

[insert_name]

On 9/23/2019 at 1:13 PM, kerbiloid said:

Wrong went with Earth, Venus is proper.

P.S.
Venus couldn't be Earth-like at least because she doesn't have continental platforms.
It hasn't been affected by a close interaction with another major body (the proto-Moon), so it wasn't rotated and partially melted.
So, its core extraction happened slower, smoother, without continents and other drama.
So, it keeps the original rotation, its light elements have been slowly exhausted from the minerals, and formed the atmosphere.
It's close to the Sun, so it was too hot to condense water before it has been splitted and dissipated.

The Mars presumably has been hit by a Pluto-sized body (a half of it is one big crater). So, it's fast, too.

We don't know much about the interior structure of Venus, and the surface is relatively new so it would be difficult to determine what has impacted it, also it does have continental platforms in the form of Ishtar and Aphrodite terra

[cubinator]

Venus apparently has had significant volcanism in the past, it may even be fairly active in recent history. This releases a lot of CO2 which on Earth gets picked out of the atmosphere by plants and algae. Venus doesn't have any of those, so the greenhouse gases just build up and make the planet hotter and hotter.

On 9/23/2019 at 12:06 PM, DDE said:

So, a theory pursued by guys and gals at Goddard is that Venus's predicament is a relatively recent condition (~715 mln years) and it was preceded by distinctly Earthlike conditions. This aligns well with the fact that Venus's surface, all of Venus's surface, is about that old, indicating a global resurfacing far in excess of anything observed on Earth.

I don't know that we can tell anything about Venus' condition earlier than the 715 My age you cite, it may have been resurfaced completely many times. Earth has had similar resurfacing events (though more slowly), and the oldest ocean crust is only about 140 My old. We only have a few places with rock older than 1-2.5 billion years old. We can trace the continents back to Pangaea, and further back to Rodinia, but there may have been many supercontinents prior which we have no way of knowing about. But we know Earth has had its oceans for all that time.

Venus may well have been similarly inhospitable prior to this most recent resurfacing.

Spoiler

Though I'm now intrigued by the idea of a sci-fi story set around 2100 where civilizations developed on Venus 710-800 Mya and escaped the planet, and humans are discovering remains of what they left behind...

 

[kerbiloid]

2 hours ago, insert_name said:

We don't know much about the interior structure of Venus, and the surface is relatively new so it would be difficult to determine what has impacted it, also it does have continental platforms in the form of Ishtar and Aphrodite terra

It mostly has cramped crust areas covered with "tesseras", which are presumably a result of cooling,
And it doesn't have a magnetosphere, so an active core.
It has nothing like terrestrial oceans, so its occasional continental plates are just areas of exhausted minerals, nothing compatible to billion-years-aged drifting Earth continents which probably appeared on the core creation as a huge supercontinent when underlaying lightweight material was replaced with quickly sinking.layer of melted iron slabs like a huge plume.

Without lunar shock, Venus differentiation and degasation looks much more calm and smooth, so the core appeared not so active, and makes no magnetosphere.
And it definitely had massive volcanism across/along all its surface because its degasation was happening uniformly, everywhere, unlike the Earth.
So, of course its surface is relatively young and full of volcanism traces, unlike the Earth surface.

1 hour ago, cubinator said:

This releases a lot of CO2 which on Earth gets picked out of the atmosphere by plants and algae.

It also released corresponding amount of water quickly lost due to absence of ozone layer caused by absence of magnetosphere.
And of sulfur oxides now bound into sulfic acid clouds with remains of that water.

1 hour ago, cubinator said:

it may have been resurfaced completely many times.

Unlikely, as it has areas of tesseras. Unlikely its crust could cool more than once.

1 hour ago, cubinator said:

Earth has had similar resurfacing events (though more slowly)

Earth gets resurfaced much faster thanks to active geology and continental drift.
Venus is a frozen pot of boiled milk.
The milk was slowly heating due to the core extraction, then at once boiled and the surface got covered with boiling foam, all at once.
Now the Venus surface is a film of solid froth. Of course, it's young because the milk boiling was the last thing happened before the fire got off, and it happened not so long ago.

***

Venus is what an Earth-like planet should be by default unless it's properly shocked by a future Moon.

The Moon is a defibrillator starting the Earth heartbeating, and an unstoppable heart-lung machine making tides.
(Even when it's a piece of useless slag in the sky).

Usually an Earth-like planet should never get a heartbeating and stays a Venus.

***

Also, it doesn't matter if there still is volcanism on Venus.

Because the Earth volcanoes appear and disappear due to continental drift, crust subduction, and other active geology.
While hypothetical Venusian volcanoes are just last bubbles of the milk foam. So, they probably add nothing to the picture even if they exist.

Edited September 25, 2019 by kerbiloid

[MinimumSky5]

@DDE Do you have a link to a write up on this?

I've always been told that Venus has a very low rate of crustal recycling due to a very low level of water in the aesthenosphere, which means that Venus's upper mantle is too viscous to support proper plate tectonics. Venus's geothermal (Cytheriothermal?) heat load has nowhere to go without plate tectonics, so it just builds up in the upper mantle until almost the entire crust breaks up and gets covered in lava. This has always been seen as Venus's default state since its creation, so I wonder what new analyses has lead them to this? 

[kerbiloid]

Of course it should dramatically lack the water after the permanently increasing smooth degasation reached its peak about a billion years ago and resulted into a total massive volcanism which spent all available fluids from the upper lithosphere, leaving the frozen lava foam everywhere.

Edited September 25, 2019 by kerbiloid

[KerikBalm]

The new article assumes a slow rotation rate. It also assumes similar topography with the "continents" in their current position, so that most of the water was not at the equator.

I saw another (older) study showing that with significant oceans and its closer position to the sun, that tidal forces would slow its rotation to about what it is now (starting at a much faster rotation than now, but still much slower than earth) in 50-100 million years. So, it may just be that oceans will tidally lock a planet faster, so being close to a star is a problem for more than just the temperature.*

The global resurfacing events thought to occur in the past of Venus, I thought were because of the effect of water on plate tectonics... that the water disappears, and then plate tectonics stops, then you get periodic massive resurfacing, instead of more continuous resurfacing like Earth has.

This brings up a question, did the water go away first, or the plate tectonics? Does rotation affect plate tectonics? does it affect the magnetic dynamo?

*which makes red dwarves even worse, because to get sufficient heat, the planet needs to be much closer (proportionately, because of the lower energy output to mass ratio), if it has oceans, it will tidally lock even faster.

 

[kerbiloid]

Why do they call the Venus rotation "slow" and "opposite"? Why should it be faster and in another direction?

The Earth and other planets are moving along the orbit rotating like a "rolling wheel".
The Venus is orbiting like a "wheel rolling back", I don't know how to describe better. They call it "in opposite direction".

A stoneball is orbiting around the sun in a torus of dust.
Originally it doesn't rotate (because it doesn't exist).

Sometimes the stoneball collides with dusticles, and every hit (always non-central due to finite sizes) pushes it, making to rotate.

When a dusticle is in farther orbit, the stoneball moves faster, and hits the dusticle with farther front quadrant, a "forehead".
When a dusticle is in lower orbit, the stoneball moves slower, and the dusticle hits the stonevball in its rear lower quadrant, in a "donkey".

As we can see, any dusticle hits the stoneball rotating it in same direction, "forehead retrograde, donkey prograde", i.e. enforces its rotation in direction a "wheel rolling back", i.e. like the Venus.

Delta-V between the stoneball and the dusticle is negligible, ~Rplanet/(2 Rorbit), i.e. ~1 m/s for the Earth and Venus.
As we can see, (2 pi * 6 400 000 / 86400 / 1) gives ~450 Earth days of rotation period. I.e. "months".

So, the natural native rotation of a stone planet is "slowly as a wheel rolling back", i.e. exactly like Venus.

So, that's the Venus who has "direct", non-disturbed rotation.
Others, like the Earth and Mars, are victims of obstacles.

Gas giants appear by consuming enormous, whirling gas clouds, so they have another way of their rotation appearance.

***

If Venus is at least minimally "tidally locked", then why Earth isn't in any degree. It's just for 40% farther.

And that the Venus (unlike the wounded Earth) has the proper, undisturbed rotation, is another evidence of absence of any catastrophic collision in Venusian history.

***

31 minutes ago, KerikBalm said:

The new article assumes a slow rotation rate. It also assumes similar topography with the "continents" in their current position, so that most of the water was not at the equator.

I saw another (older) study showing that with significant oceans

And this perfectly matches the case when the degasation was smooth and uniform, so pools and silicate pancakes appeared here and there, and no continental drift ever happened.

While the Earth survived a shock event when it was partially melted, the gravitational differentiation increased, the core extraction happened fast and non-symmetrical, and large amount of silicate was thrown from below as a plume/jet making the crust non-symmetrical and non-uniform.

Edited September 25, 2019 by kerbiloid

[KerikBalm]

Please provide citations to any of the above. Its basically completely wrong.

Your comment about the natural rotation direction is completely wrong. Note that Venus rotates in the same direction as every other body in the solar system. The difference is that it is so slow that its longer than its year, so from the surface, its apparent rotation, using the sun as a reference, seems to be reversed. Against the "fixed" stars, it rotates the same direction, just very slow. *edit*, oops, I was wrong on that point, but still, simulations of planet formation show that Venus's rotation is not the normal one, something funky had to have happened.

Yes, Earth is 40% farther out, that's a big difference.

https://en.wikipedia.org/wiki/Tidal_locking#Timescale

Quote

tlock≈ωa6IQ3Gmp2k2R5{\displaystyle t_{\text{lock}}\approx {\frac {\omega a^{6}IQ}{3Gm_{p}^{2}k_{2}R^{5}}}}

where

• ω{\displaystyle \omega \,} is the initial spin rate expressed in radians per second,
• a{\displaystyle a\,} is the semi-major axis of the motion of the satellite around the planet (given by the average of the periapsis and apoapsis distances),
• I{\displaystyle I\,} ≈0.4msR2{\displaystyle \approx 0.4m_{s}R^{2}} is the moment of inertia of the satellite, where ms{\displaystyle m_{s}\,} is the mass of the satellite and R{\displaystyle R\,} is the mean radius of the satellite,
• Q{\displaystyle Q\,} is the dissipation function of the satellite,
• G{\displaystyle G\,} is the gravitational constant,
• mp{\displaystyle m_{p}\,} is the mass of the planet, and
• k2{\displaystyle k_{2}\,} is the tidal Love number of the satellite.

Now we see that it depends on the 6th power of SMA! For precision, its Sma is 1.3825 x larger. This to the 6th power increases tidal locking time by a factor of 7

As for the R⁵ notation, that's offset by I, which is related to mR² . m is basically R³ and density, so the I = 0.4 mR²  is similar to 0.4 R⁵ * density... so the R⁵ cancels out on the top and bottom, and Earth's greater density increases locking time.

Earth's rotation is 1/4 what it used to be anyway. Yes, it did get a lot higher initial rotation rate because of that collision, it seems.

 

https://newatlas.com/ancient-venus-ocean-slow-down-rotation/59808/

Edited September 25, 2019 by KerikBalm

[kerbiloid]

https://en.wikipedia.org/wiki/Tidal_locking#List_of_known_tidally_locked_bodies

Trying to find Venus.

 

33 minutes ago, KerikBalm said:

Please provide citations to any of the above. Its basically completely wrong.

In Newton's laws we trust. And momentum conservation, too. Simulations are secondary and change not once.

Edited September 25, 2019 by kerbiloid

[KerikBalm]

Yea, its not completely tidally locked, but it rotates so slowly it might as well be for the purposes of life. We aren't really talking about tidally locked vs not, but rather the effect of slowing rotation significantly when a planet still has liquid water, and the effect on how long that water can last when daytime temperatures start to skyrocket, even as average temperature isn't so bad.

You can cite newton's laws and conservation of momentum, but you still haven't actually demonstrated anything, and your explanation as to why you think venus has the " proper, undisturbed rotation" is frankly incoherent. When I try to be the most generous and make sense of what you are trying to say, it comes out as obviously erroneous.

Since its the only major body we know of orbiting in that direction, and even then just very slowly, it flies in the face of Occam's razor to say that every other major (and nearly every other minor body) in the solar system has had its rotation "disturbed" to rotate (much faster) in the same direction. If this is a random disturbance that overwhelms the "proper rotation", shouldn't we see a mixture of bodies that rotate faster than Venus in both directions?

Edited September 25, 2019 by KerikBalm

[DDE]

9 hours ago, MinimumSky5 said:

 

@DDE Do you have a link to a write up on this?

I've always been told that Venus has a very low rate of crustal recycling due to a very low level of water in the aesthenosphere, which means that Venus's upper mantle is too viscous to support proper plate tectonics.

Unfortunately, the papers I see mostly just estimate the amount of water.

https://meetingorganizer.copernicus.org/EPSC-DPS2019/EPSC-DPS2019-1846-1.pdf