The Making of Hell:

[beecee]

https://www.bangor.ac.uk/news/latest/new-research-at-bangor-university-helps-shed-light-on-the-possibility-of-past-life-on-venus-40747

New research at Bangor University helps shed light on the possibility of past life on Venus:

Whilst today Venus is a very inhospitable place, with surface temperatures hot enough to melt lead, geological evidence, supported by computer model simulations, indicate it may have been much cooler billions of years ago and had an ocean, and so have been very similar to Earth.

more at link.........

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https://www.universetoday.com/142307/theory-proposes-that-venus-could-have-been-habitable-but-a-large-ocean-slowed-down-its-rotation-killing-it/#more-

 

extract: 

"This suggests that the tidal brake could have slowed down Venus to its current rotation in just 10 to 50 million years. Since it was this reduced rotation rate that caused Venus’ oceans to evaporate on its Sun-facing side, leading to the runaway greenhouse effect, this tidal disruption effectively robbed Venus of its habitability in what was (from a geological standport) a pretty short time frame".

"In other words, tidal-braking may be the reason why Venus went from being an ocean-covered world that could have very well support life to a hot, hellish environment where nothing could survive – and in the space of a few eons. These findings could also have implications for the study of extrasolar planets, where many “Venus-like” worlds have already been found".

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Edited May 26, 2019 by beecee

[MigL]

Interesting, BeeCee.

But the rotation didn't just slow down to current levels.
It actually went retrograde.
I could see this for an outer planet, orbiting out of the plane of the ecliptic, suggesting capture.
But Venus orbits close to the Sun, and in the plane of the ecliptic, suggesting it was formed from the primordial gases/dust that made up the solar system.
Tidal forces could not have made its rotation retrograde in that case.

This is just a theory.
But my money is still on the collision theory.

[beecee]

49 minutes ago, MigL said:

Interesting, BeeCee.

But the rotation didn't just slow down to current levels.
It actually went retrograde.
I could see this for an outer planet, orbiting out of the plane of the ecliptic, suggesting capture.
But Venus orbits close to the Sun, and in the plane of the ecliptic, suggesting it was formed from the primordial gases/dust that made up the solar system.
Tidal forces could not have made its rotation retrograde in that case.

This is just a theory.
But my money is still on the collision theory.

The retrograde scenario is mentioned in the article and does suggest an inter-planetary collision. Certainly, tidal forces alone, could not have been the cause of the retrograde motion.

[Moontanman]

The fact that the Sun has increased in it's output as much as 30% over that time span wasn't mentioned.  

 

http://faculty.wcas.northwestern.edu/~infocom/The Website/evolution.html

 

Quote

In short, in the end, the nuclear furnace at the center of every star begins to overheat.  To put numbers on this, when the Sun was formed 4.5 billion years ago it was about 30% dimmer than at present.  At the end of the next 4.8 billion years, the Sun will be about 67% brighter than it is now.  In the 1.6 billion years following that, the Sun's luminosity will rise to a lethal 2.2 L_o.  (L_o = present Sun.)  The Earth by then will have been roasted to bare rock, its oceans and all its life boiled away by a looming Sun that will be some 60% larger than at present.⁴  The surface temperature on the Earth will be in excess of 600 F°. But even this version of the Sun is still stable and golden compared to what is to come.

 

[beecee]

1 hour ago, Moontanman said:

The fact that the Sun has increased in it's output as much as 30% over that time span wasn't mentioned.  

 

http://faculty.wcas.northwestern.edu/~infocom/The Website/evolution.html

That would have added to the process of evaporation of the Oceans presumably.

Either way it tells me that any stellar system, and the ability to support life [as we know it] largely can depend on the age of the system. eg: Our own system in 3 billion years, could see Mars probably more attuned to life [possibly again] 

Then we have the process of planetary migration, although so far the only literature I have read on that process, concerns gaseous giants. Could it also happen with terrestrial planets?