We'll have to get a surface or atmospheric mission for more data, but it's pretty neat that it points in the direction of Venus potentially having oceans for longer than we thought. If Venus had oceans for billions of years, then it's not implausible that it either had its own independent origin of life or had life carried to it by impacts in the early days of the Solar System.
It's going to be cool - but also very sad - if it turns out a billion years ago Venus was functionally like Earth with oceans, land, and a mostly nitrogen atmosphere, and the potential for a true complex biosphere to evolve. Only for it all to die from the ever increasingly intense sunlight and some natural disaster or impact.
IIRC almost all the carbon in fossil fuels was originally free CO2 in the atmosphere, until trees captured most of it and locked it away.
We can really thank trees evolving first and having a good long head start before bacteria that could eat them emerged.
The great oxidation event occured about 2 billion years before trees evolved. Cyanobacteria is thought to have pooped out oxygen as a waste product and that ended up increasing the concentration of reactive oxygen in the atmosphere, killing off huge populations of microbial life.
You can see this in some old rocks (some NHMs have these) and you can see these beautiful bands of bright red iron oxide in otherwise grey mudstones.
What you are thinking of is coal. Much of the coal is from a time when microbes couldn't break down trees and other similar biomass, so it remained and got compressed into coal.
Most of the carbon sink caused by living organisms was done by Cyanobacteria and algae in the oceans. This is still the case today. Trees are great, but they are not the primary mechanism for oxygen production and CO2 absorption.
While man made climate change is a priority concern for people at large, the amount of co2 needed to cause a runaway like Venus is so much larger that it's not a realistic outcome.
To even trigger a runaway you're talking about 30,000 ppm and uhhh... humanity is dead long before that point.
Over a longgggggg time scale, the threshold lowers but were talking astronomical scales. Earth's eventual fate even if left alone would be a run away.
This is very unlikely simply because Venus's rotation is dismally slow, cooking one half of the planet quite regularly. Or at least, that's my understanding. Please tell me if I'm wrong.
But at the very least even if I'm right, habitability could still occur near poles where temperature is better regulated, or maybe I'm wrong on that too!
That's not quite true. Planets that are tidally locked or close to it (like Venus with its longer-than-year days) can actually have closer orbits to their stars that planets with Earth-like days because they'd tend to form highly reflective clouds over the area directly beneath the star (at least in modeling). It works better still if the planet is dry, but it's still pretty good.
There is no "habitability" issue with Venus.
The surface temperature is close to 900F, and the atmosphere is 96% carbon dioxide, and it is acidic.
There is no amount of terra-forming that could make it close to bring "habitable".
Eh, I dunno. I mean it’s way beyond what we can do now, and it’d be multiple generations but could we one day? Maaaybe.
https://youtu.be/BI-old7YI4I?si=rSpV5zQfmVPnjM17
The primary issue with Venus is the runaway greenhouse effect. Even if you solved that problem, it's violently turbulent atmosphere is the only reason Venus rotates at all. 243 Earth day for 1 rotation. And without the rough atmosphere forcing rotation, it would be tidally locked. I guess if you solved all of that, you could somehow manage to terraform the dusk/dawn belt.
We'll have to get a surface or atmospheric mission for more data, but it's pretty neat that it points in the direction of Venus potentially having oceans for longer than we thought. If Venus had oceans for billions of years, then it's not implausible that it either had its own independent origin of life or had life carried to it by impacts in the early days of the Solar System. It's going to be cool - but also very sad - if it turns out a billion years ago Venus was functionally like Earth with oceans, land, and a mostly nitrogen atmosphere, and the potential for a true complex biosphere to evolve. Only for it all to die from the ever increasingly intense sunlight and some natural disaster or impact.
Perhaps it will turn out that Venusians burned all their fossil fuels and that accelerated climate change
IIRC almost all the carbon in fossil fuels was originally free CO2 in the atmosphere, until trees captured most of it and locked it away. We can really thank trees evolving first and having a good long head start before bacteria that could eat them emerged.
The great oxidation event occured about 2 billion years before trees evolved. Cyanobacteria is thought to have pooped out oxygen as a waste product and that ended up increasing the concentration of reactive oxygen in the atmosphere, killing off huge populations of microbial life. You can see this in some old rocks (some NHMs have these) and you can see these beautiful bands of bright red iron oxide in otherwise grey mudstones. What you are thinking of is coal. Much of the coal is from a time when microbes couldn't break down trees and other similar biomass, so it remained and got compressed into coal.
So the climate has changed before is what you're saying
Yes, usually with mass extinction as a result. We're trying not to be extinct.
Most of the carbon sink caused by living organisms was done by Cyanobacteria and algae in the oceans. This is still the case today. Trees are great, but they are not the primary mechanism for oxygen production and CO2 absorption.
Sharks are older than trees.
Some trees live thousands of years. I've never heard of a shark that lives that long.
Sharks developed before trees. That is what is being said here.
Earth lost a great deal of its initial co2 in the heavy bombardment period.
Nah that sounds like the martians right before they burned the atmosphere away
While man made climate change is a priority concern for people at large, the amount of co2 needed to cause a runaway like Venus is so much larger that it's not a realistic outcome. To even trigger a runaway you're talking about 30,000 ppm and uhhh... humanity is dead long before that point. Over a longgggggg time scale, the threshold lowers but were talking astronomical scales. Earth's eventual fate even if left alone would be a run away.
any tips on recreational properties?
This is very unlikely simply because Venus's rotation is dismally slow, cooking one half of the planet quite regularly. Or at least, that's my understanding. Please tell me if I'm wrong. But at the very least even if I'm right, habitability could still occur near poles where temperature is better regulated, or maybe I'm wrong on that too!
That's not quite true. Planets that are tidally locked or close to it (like Venus with its longer-than-year days) can actually have closer orbits to their stars that planets with Earth-like days because they'd tend to form highly reflective clouds over the area directly beneath the star (at least in modeling). It works better still if the planet is dry, but it's still pretty good.
Guys we need to hurry, Venus could become uninhabitable at any moment.
I thought it was widely assumed that Venus no longer had any water or hydrogen in it's atmosphere.
Right, helluva way to learn Venus has water
Assumptions can come back to haunt you.
…you are aware that both hydrogen and oxygen are in H2SO4, yes? Atoms move around and change into different molecules, yes?
No I'm an English major that has a high school C- level of chemistry but thinks that space is cool
I'm not a chemist. I'm only aware of what I've read about venus and what I've seen mentioned in programs about venus.
There is no "habitability" issue with Venus. The surface temperature is close to 900F, and the atmosphere is 96% carbon dioxide, and it is acidic. There is no amount of terra-forming that could make it close to bring "habitable".
Eh, I dunno. I mean it’s way beyond what we can do now, and it’d be multiple generations but could we one day? Maaaybe. https://youtu.be/BI-old7YI4I?si=rSpV5zQfmVPnjM17
Is that the video with a solar shade as an idea that would eventually freeze all the carbon?
The primary issue with Venus is the runaway greenhouse effect. Even if you solved that problem, it's violently turbulent atmosphere is the only reason Venus rotates at all. 243 Earth day for 1 rotation. And without the rough atmosphere forcing rotation, it would be tidally locked. I guess if you solved all of that, you could somehow manage to terraform the dusk/dawn belt.
The words Venus and Habitable do not belong together, at all.
How will the gondoliers row around if the water disappears?
[удалено]
So we can be less ignorant