- "Several upcoming missions, including NASA’s DAVINCI (Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging)"
DAVINCI is actually cancelled in the latest budget request. For obvious reasons, the NASA press office (the OP) won't talk about this. But 50% of NASA's science funding is gone.
Supposedly, the Senate Launch System boondoggle is being killed, but not until 2027, by which time the Artemis III moon landing is supposed to happen. Since Artemis II (manned flight around the moon) has been delayed again, that's unlikely.
Ninth Space-X Starship/Super Heavy launch some time this month.
No. Let's first feed the homeless and struggling, and fix the crisis that are affecting ordinary people.
Governments should have been able to do that up until now. Instead the government has been shipping money overseas and spending it on foreigners for far too long. That's why people are angry and they will cut anything and everything that they deem as not part of the "core" proposition of government.
> No. Let's first feed the homeless and struggling, and fix the crisis that are affecting ordinary people.
I may be wrong, but it's not money that's the problem; there's plenty of money. (I would also point out the NASA budget is a miniscule spec of dust compared to the total budget.)
It seems to me the problem is organization and politics - actually doing the right things to address these problems.
It's like, say, Microsoft. They can't run a successful project to save their lives. This is an organizational and cultural problem. Large organization, lots of politics, enough money that success or failure is not critical to survival.
> Governments should have been able to do that up until now. Instead the government has been shipping money overseas and spending it on foreigners for far too long.
I would remind everyone that congress sets the budget. This is merely a proposal from the president. The proposal is regularly ignored. Nothing has been cancelled, yet, merely proposed to be cancelled.
Haha Venus keeps reminding us how little we know about rocky planets. The crust movement stuff is particularly interesting—kind of like plate tectonics-lite?
Are you just looking at the photo to determine volcanoes and craters? Wouldn't we expect that with so much atmosphere on Venus, that meteors would have a much harder time reaching the surface? That is, much larger ones would burn up or get deflected than on Earth.
I remember that episode being excellent! Scientists could tell that Venus’s crust was somehow reforming because of the crater pattern but the didn’t know whether it was gradual change or something catastrophic, and the thickness of the crust would point to one way or the other but they didn’t have that data.
> The paper used modeling to determine that its crust is about 25 miles (40 kilometers) thick on average and at most 40 miles (65 kilometers) thick.
I wonder if Venus could be terraformed via a sun shield placed in orbit around it. How big would it have to be to reverse the runaway greenhouse effect?
Part of the problem is having too much atmosphere. In the original Cosmos Carl Sagan talked about a hypothetical solution where we capture asteroids, and throw them at Venus in such a way that they just nick the atmosphere and knock large quantities of atmosphere out into space. One you reduce atmospheric pressure to a certain level, things could become habitable.
Then throw in iron form the atseroid belt to react with it to form carbonates. Venus is dry so brining in hydrogen form the outer planets would be necessary anyway to form wate r and thta will account for a good bit. Garden the surface so subsurface rocks which might react with the atmosphere cna absorb some. (Assumign the subsurface rocks are thta reactive.) Scoop it off with smaller versions of the same scoops used to harvets hydrogen from the gas giants.
I thought the Venus theory was runaway greenhouse driven initially by water vapor. Going off memory, H2O is roughly 10 times as effective a greenhouse gas as CO2, with Venus being closer to the sun A larger percentage of water ended up in vapor form, leading to a feed back loop where the increased heat pushes more water to vapor leading to more heat, eventually liberating the co2 from the rock, making everything worse, ending up with the current situation where venus has way too much atmosphere.
Which is the long way to say, I think there is a lot of water on venus.
Moreover, I think Venus has lost most of its hydrogen to space, so you can't even make water anymore. Hydrogen escapes the atmosphere relatively easily for Earth- and Venus-sized planets[1], and the vaporization of all the water and subsequent disassociation[2] of H2O allowed the hydrogen to escape into space.
Couldn't we just build a MegaMaid and suck the atmosphere out? If we're going to go sci-fi, it seem easier to hoover it out than capture an asteroid and nick the atmosphere just right.
I’ve read that a large asteroid could be positioned at a particular Mars L point and it would protect the planets atmosphere from being stripped by the sun.
That would require a lot of energy to ensure the gasses escape Venus' gravitational pull, which would in turn effectively be a rocket. So then we'd be adjusting to ensure we don't mess with Venus' orbit too much.
Venus outweighs its atmosphere by about 10,000 times. This is actually less than I thought -- for comparison Earth outweighs its atmosphere by over 1,000,000 times, which is still far less than I would have guessed.
Venus's escape velocity is less than 1/3rd of its orbital velocity. According to google, Venus's orbit, despite being very circular, causes its velocity to vary by a KM/s from aphelion to perihelion.
So I believe you could send all of Venus's atmosphere off permanently into space at the cost of about 1/30,000th of Venus's orbital velocity, meaning you could very slightly circularize its orbit further.
I recall one of the plans being to use the sun shield to entirely freeze out the atmosphere, then use a mass driver to chuck most of the CO2 into space. I don't recall exactly where that was supposed to be on the feasible to scifi spectrum.
I'd rather try to keep the carbon around for organic molecules. Are we sure we can't get in enough H2O and N to balance it out and build a nice thick biosphere?
I guess I'll count that as another reason to prefer managing it in situ. But it might be fine, actually? Slow re-accretion can probably be managed by whatever terraforming process we've kickstarted while most of it was gone.
Oh wait, I remember the plan, ship it to Mars so they can have some decent atmospheric pressure.
If the commenters are discussing diverting enough meteors to terraform Venus, there's enough fantasy to consider using nukes to apply the necessary torque to speed the orbit up
With that much atmosphere that’s a lot of tidal forces too, if you just get some I to orbit.
But the question. Is do you spin it backward or slow it down to spin it the right way, creating a situation where one side of the planet always faces the sun for a while. Might be an opportunity to freeze and cart off the other side of the atmosphere…
If you're interested in human habitation of Venus overall, you may find it interesting to learn Venus is probably preferable kept at about its current temperature or only made a little colder.
See, the atmosphere at ~50 altitude... happens to be about 1 bar (which happens to be Earth's atmospheric pressure ASL)... and happens to have temperatures that can support human and plant life!
And better still, the atmosphere being mostly co2 with a little nitrogen actually means normal Earth air is a lifting gas! Starting to see where this is going?
It's not too hard to imagine the skies of Venus full of floating habitats that move to stay in the sunlight, or occasionally dock with tethers or balloons carrying cargo from extremely reinforced mining facilities deep underground (where they could be much more protected most of the time from the pressure/temperature/corrosion) -- a future where people (or machines!) might scoff at the idea of cooling off Venus and losing out on such an excellent habitation zone, one which could also fairly easily support elevated runways or launch platforms to more cheaply reach space from.
With Venus also having 91% of Earth's gravity, and those atmospheric conditions at high altitudes that add some radiation shielding and would probably let a human worker only need a very limited suit more akin to a hazmat or firefighting suit with SCBA to work outside habitats... Venus is actually easily the single best planet for humans to live on after Earth!
(Can you tell I'm writing a story set there? Hehehe)
You need to give us more. I feel that just the heat is a tricky problem, even at 50km altitude. Anything todo with Venus is very much scifi at the moment. It might be easier than a moon base but we can not know.
Oh it wouldn't be easier than a moon base or simple orbital habitats. And as for Venus being scifi, anything to do with space colonization period is scifi right now; humans haven't even stepped foot on another celestial body of any kind in over half a century.
Rather my meaning was that it's (a little shockingly) the best suited planet for humans in terms of most closely and reliably resembling conditions humans could survive in, which relates to the terraforming notions I was replying to.
It'd be overwhelmingly harder to make all of Venus Earthlike than to just use the existing relatively Earthlike regions of the upper atmosphere to our advantage along with their unique properties. Cool off Venus and you just get a big ocean of liquid or frozen co2 to have to deal with after a loooong time and a lot of construction. Keep it like it is and a fraction of the resources/effort will yield far more utility while we can still enjoy a segment of the atmosphere.
1. "Humidify" the atmosphere by crashing comets into Venus. This will also allow us to create a temporary "cloud" around Venus that can shield it from the Sun and lower down the temperature.
2. Once the temperature is low enough, Venus will get oceans on its surface.
3. At this point, CO2 can be split into carbon and oxygen. Oxygen will be immediately bound by the huge amount of under-oxidized iron on the surface, and carbon can be buried under the new ocean. Essentially, carboniferous age for Venus.
4. Once this is done, the atmosphere will be mostly nitrogen (at ~3 bar) and people could live there with just respirators. Eventually, once the surface iron is oxidized, the atmosphere can even be made breathable.
Apparently, this can be done within 2000-5000 years without any exotic-level engineering.
My understanding is that it was water that started the whole thing. water vapor is about ten times as effective a greenhouse gas as co2. and the runaway heat started with too much water vapor(closer to to the sun I think), leading to more heat, leading to more water vapor. eventually it got hot enough to start liberating co2 out of the rocks. leading to the current situation today where venus has way too much atmosphere.
Which is to say, putting a ring around venus to block the sun may have merit, but adding more water sounds like pouring petrol on a fire.
Depending on a size, probably on the order of tens of thousand.
Comets in the Oort cloud take very little energy to put on a collision orbit, the Sun barely holds them gravitationally, orbital speeds in the Oort cloud are measured in _meters_ per second. So they require (relatively) little energy to put them into a required orbit. It might be doable with just regular thermonuclear charges.
It will then take these comets more than a thousand years to "fall" from the Oort cloud.
Venus is a damned shame. Had planetary evolution gone just slightly differently, the solar system could have had two habitable water planets. Mars, owing to its size, was never going to cut it, but Venus might have.
I wonder how a system with 2 planets with intelligent lifeforms would've developed culturally and politically... if both civilizations grew at the same rate, 2 Galileos would've looked at the other planet and figured out "we have neighbors!", but it'd be several hundred more years before communication could be done. Even know we don't have manned missions to Mars or Venus...
> a system with 2 planets with intelligent lifeforms
That is an extremely unlikely scenario because both intelligent life forms would have had to evolve before either of them developed space flight. It took homo sapiens 4 Gyr to evolve in the first place but only 100 kyr to develop space flight after that. So the odds are slim to none.
Does intelligent life mean only human-level intelligence? If we found a bunch of chimp-like animals running around, would that count as intelligent life?
Sure, but our interactions with chimp-like intelligence on another planet are unlikely to be substantially different from our interactions with chimp-like intelligence on this planet. It only gets interesting when both are more or less evenly matched, and that is extremely unlikely.
And our interactions with same-level intelligence on another planet are unlikely to be substantially different from our interactions with same-level intelligence on this planet. We've seen this before when people from one continent encountered those from another. In fiction, we show (via projection) how we might treat other intelligent life forms (every accusation is a confession).
I don't know why you'd think it'd be several hundred more years before communication could be done. If they can both observe each other, then all that's left is to devise a way to signal back visually. Seeing proof of one's neighbors would definitely drive people to develop ways to communicate, though I guess both planets would need to be similarly driven in order to establish communication.
Using Hohmann transfer, I believe the energy cost is the same both ways. Of course as you point out we have the Moon, "they" have none. So we'd have plenty of rocks to throw.
That said, we'd have to throw much bigger rocks to penetrate their atmosphere. And the likely (to me) actual plans would be:
Us: launch to the Moon, set up there, launch rocks from the Moon to Venus.
Venusians: launch and travel to the asteroid belt, launch an asteroid toward Earth.
The more I think about it, the more I realize that our plan would be the same as theirs: we'd both be heading for the asteroid belt, because nothing we could reasonably launch from the Moon would put a dent in Venus with that atmosphere.
And if we assume they actually can launch through that atmosphere, we're screwed: if they can do that, they're way ahead of us.
Same energy to enter the orbit, but the kinetic energy per unit mass should be a whole lot higher at Venus than Earth, so each of your shots count for a lot more. But yeah, the main advantage is the moon. And you wouldn't launch things from the moon. You would launch pieces of the moon from mass drivers.
The situation I replied to assumed they were both inhabitable planets which I assume means Earth like atmosphere on Venus. The thick atmosphere complicates things, but I don't think you actually have to hit the ground. Tunguska didn't even get near the ground and it still leveled 1000 km^2. Also if Venus has the atmosphere there's no point of a war since there's no benefit to conquest in either direction.
If the Venusians had the technology to lob rocks, they'd have the technology to do so from the asteroid belt. They don't need to mine them their own non-existent moon.
- "Several upcoming missions, including NASA’s DAVINCI (Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging)"
DAVINCI is actually cancelled in the latest budget request. For obvious reasons, the NASA press office (the OP) won't talk about this. But 50% of NASA's science funding is gone.
https://spacenews.com/white-house-proposal-would-slash-nasa-...
> But 50% of NASA's science funding is gone.
The proposed cuts to science are catastrophic, but there’s still time to call your Congressperson.
https://aas.org/posts/news/2025/05/week-of-action
Supposedly, the Senate Launch System boondoggle is being killed, but not until 2027, by which time the Artemis III moon landing is supposed to happen. Since Artemis II (manned flight around the moon) has been delayed again, that's unlikely.
Ninth Space-X Starship/Super Heavy launch some time this month.
> Senate Launch System
Where can I contribute to put all the senators in a spaceship and yeet them into outer space?
I propose we just yeet one of them and see if the rest clean up their act.
I remember writing to my red congressman once and they wrote back telling me how wrong I was. Democracy felt different after that.
No. Let's first feed the homeless and struggling, and fix the crisis that are affecting ordinary people.
Governments should have been able to do that up until now. Instead the government has been shipping money overseas and spending it on foreigners for far too long. That's why people are angry and they will cut anything and everything that they deem as not part of the "core" proposition of government.
> No. Let's first feed the homeless and struggling, and fix the crisis that are affecting ordinary people.
I may be wrong, but it's not money that's the problem; there's plenty of money. (I would also point out the NASA budget is a miniscule spec of dust compared to the total budget.)
It seems to me the problem is organization and politics - actually doing the right things to address these problems.
It's like, say, Microsoft. They can't run a successful project to save their lives. This is an organizational and cultural problem. Large organization, lots of politics, enough money that success or failure is not critical to survival.
> Governments should have been able to do that up until now. Instead the government has been shipping money overseas and spending it on foreigners for far too long.
In what ways?
the government that slashes your science budget is the same government that would never feed the homeless, unless it was -to the sharks.
What is the Trump administration doing to feed the homeless and struggling?
Programs like SNAP benefits (a.k.a. food stamps) have always been top of the list of what Republicans want to cut.
The full proposed budget is available at https://www.whitehouse.gov/wp-content/uploads/2025/05/Fiscal... folks are interested in seeing the whole picture and reasoning.
> reasoning
The justification? I don't think they are open about their reasoning.
Typo in your URL. replace the last l with a d ....".pdf" not ".plf"
Thanks! Fixed.
And no thanks to autocorrect.
HTTP 404
wp-content?
Am I the only one shocked to see wordpress here.
The WH website switched from Drupal to WordPress in 2017.
I would remind everyone that congress sets the budget. This is merely a proposal from the president. The proposal is regularly ignored. Nothing has been cancelled, yet, merely proposed to be cancelled.
That really stinks. As I said before, the US is handing all good research and science ti China.
Haha Venus keeps reminding us how little we know about rocky planets. The crust movement stuff is particularly interesting—kind of like plate tectonics-lite?
I'm blown away at the number of huge volcanos and relative lack of craters. If that's right, Venus must recycle its surface relatively often.
Are you just looking at the photo to determine volcanoes and craters? Wouldn't we expect that with so much atmosphere on Venus, that meteors would have a much harder time reaching the surface? That is, much larger ones would burn up or get deflected than on Earth.
> Scientists expected the outermost layer of Venus’ crust would grow thicker and thicker over time
I recall watching this NOVA episode in 1995 where scientists had no idea whether the lithosphere is thick or thin. Seek to 36 minutes: https://archive.org/details/VenusUnveiled/NOVA.S22E10.Venus....
I remember that episode being excellent! Scientists could tell that Venus’s crust was somehow reforming because of the crater pattern but the didn’t know whether it was gradual change or something catastrophic, and the thickness of the crust would point to one way or the other but they didn’t have that data.
> The paper used modeling to determine that its crust is about 25 miles (40 kilometers) thick on average and at most 40 miles (65 kilometers) thick.
So would that be considered “thick” or “thin”?
Thick compared to Earth, but I think it has an especially thin crust.
I wonder if Venus could be terraformed via a sun shield placed in orbit around it. How big would it have to be to reverse the runaway greenhouse effect?
Part of the problem is having too much atmosphere. In the original Cosmos Carl Sagan talked about a hypothetical solution where we capture asteroids, and throw them at Venus in such a way that they just nick the atmosphere and knock large quantities of atmosphere out into space. One you reduce atmospheric pressure to a certain level, things could become habitable.
Then throw in iron form the atseroid belt to react with it to form carbonates. Venus is dry so brining in hydrogen form the outer planets would be necessary anyway to form wate r and thta will account for a good bit. Garden the surface so subsurface rocks which might react with the atmosphere cna absorb some. (Assumign the subsurface rocks are thta reactive.) Scoop it off with smaller versions of the same scoops used to harvets hydrogen from the gas giants.
"Venus is dry"
I thought the Venus theory was runaway greenhouse driven initially by water vapor. Going off memory, H2O is roughly 10 times as effective a greenhouse gas as CO2, with Venus being closer to the sun A larger percentage of water ended up in vapor form, leading to a feed back loop where the increased heat pushes more water to vapor leading to more heat, eventually liberating the co2 from the rock, making everything worse, ending up with the current situation where venus has way too much atmosphere.
Which is the long way to say, I think there is a lot of water on venus.
https://en.wikipedia.org/wiki/Atmosphere_of_Venus
From your link:
> Lighter gases, including water vapour, are continuously blown away by the solar wind through the induced magnetotail.
There used to be a lot of water on Venus.
Moreover, I think Venus has lost most of its hydrogen to space, so you can't even make water anymore. Hydrogen escapes the atmosphere relatively easily for Earth- and Venus-sized planets[1], and the vaporization of all the water and subsequent disassociation[2] of H2O allowed the hydrogen to escape into space.
[1] See https://en.wikipedia.org/wiki/Atmosphere#/media/File:Solar_s...
[2] See https://en.wikipedia.org/wiki/Atmospheric_escape
Couldn't we just build a MegaMaid and suck the atmosphere out? If we're going to go sci-fi, it seem easier to hoover it out than capture an asteroid and nick the atmosphere just right.
Then, move the MegaMaid into an orbit around Mars and go from suck to blow. Venus has too much atmosphere, Mars has too little. Win Win.
It wouldn't do Mars any good. Lacking a magnetosphere, any atmosphere you add will get stripped away by the Sun.
The estimate I heard is it would take 100,000 years for the atmosphere to be stripped off. That’s a long long time.
I’ve read that a large asteroid could be positioned at a particular Mars L point and it would protect the planets atmosphere from being stripped by the sun.
I've read something similar, but I believe it has to be an asteroid with a magnetic field, whether permanent or electromagnet.
The atmosphere will be stripped away over a time period of millions of years though.
Something like a solar powered space elevator that just blows atmosphere into the sun
That would require a lot of energy to ensure the gasses escape Venus' gravitational pull, which would in turn effectively be a rocket. So then we'd be adjusting to ensure we don't mess with Venus' orbit too much.
Venus outweighs its atmosphere by about 10,000 times. This is actually less than I thought -- for comparison Earth outweighs its atmosphere by over 1,000,000 times, which is still far less than I would have guessed.
Venus's escape velocity is less than 1/3rd of its orbital velocity. According to google, Venus's orbit, despite being very circular, causes its velocity to vary by a KM/s from aphelion to perihelion.
So I believe you could send all of Venus's atmosphere off permanently into space at the cost of about 1/30,000th of Venus's orbital velocity, meaning you could very slightly circularize its orbit further.
Spinning it up would be handy.
We can avoid orbital drift through the magic of building two of them.
I recall one of the plans being to use the sun shield to entirely freeze out the atmosphere, then use a mass driver to chuck most of the CO2 into space. I don't recall exactly where that was supposed to be on the feasible to scifi spectrum.
I'd rather try to keep the carbon around for organic molecules. Are we sure we can't get in enough H2O and N to balance it out and build a nice thick biosphere?
There’s a book where they freeze the atmosphere then cover the ice with a thick layer of dirt. But I cannot recall which.
You'd have to shoot it out of the solar system, otherwise much of it would reaccrete onto Venus... or onto Earth!
I guess I'll count that as another reason to prefer managing it in situ. But it might be fine, actually? Slow re-accretion can probably be managed by whatever terraforming process we've kickstarted while most of it was gone.
Oh wait, I remember the plan, ship it to Mars so they can have some decent atmospheric pressure.
Venus has a retrograde day that is longer than it's year.
While the atmosphere is a big problem, even without this issue the rotation would be problematic.
If the commenters are discussing diverting enough meteors to terraform Venus, there's enough fantasy to consider using nukes to apply the necessary torque to speed the orbit up
If we're spitballing, one could simply angle the impacts of asteroids to add momentum in the desired direction.
With that much atmosphere that’s a lot of tidal forces too, if you just get some I to orbit.
But the question. Is do you spin it backward or slow it down to spin it the right way, creating a situation where one side of the planet always faces the sun for a while. Might be an opportunity to freeze and cart off the other side of the atmosphere…
Why don't we simply vaporize Venus entirely and construct our own bespoke planet in its place, if it's so damn problematic
https://memory-alpha.fandom.com/wiki/Technobabble
If you're interested in human habitation of Venus overall, you may find it interesting to learn Venus is probably preferable kept at about its current temperature or only made a little colder.
See, the atmosphere at ~50 altitude... happens to be about 1 bar (which happens to be Earth's atmospheric pressure ASL)... and happens to have temperatures that can support human and plant life!
And better still, the atmosphere being mostly co2 with a little nitrogen actually means normal Earth air is a lifting gas! Starting to see where this is going?
It's not too hard to imagine the skies of Venus full of floating habitats that move to stay in the sunlight, or occasionally dock with tethers or balloons carrying cargo from extremely reinforced mining facilities deep underground (where they could be much more protected most of the time from the pressure/temperature/corrosion) -- a future where people (or machines!) might scoff at the idea of cooling off Venus and losing out on such an excellent habitation zone, one which could also fairly easily support elevated runways or launch platforms to more cheaply reach space from.
With Venus also having 91% of Earth's gravity, and those atmospheric conditions at high altitudes that add some radiation shielding and would probably let a human worker only need a very limited suit more akin to a hazmat or firefighting suit with SCBA to work outside habitats... Venus is actually easily the single best planet for humans to live on after Earth!
(Can you tell I'm writing a story set there? Hehehe)
You need to give us more. I feel that just the heat is a tricky problem, even at 50km altitude. Anything todo with Venus is very much scifi at the moment. It might be easier than a moon base but we can not know.
Oh it wouldn't be easier than a moon base or simple orbital habitats. And as for Venus being scifi, anything to do with space colonization period is scifi right now; humans haven't even stepped foot on another celestial body of any kind in over half a century.
Rather my meaning was that it's (a little shockingly) the best suited planet for humans in terms of most closely and reliably resembling conditions humans could survive in, which relates to the terraforming notions I was replying to.
It'd be overwhelmingly harder to make all of Venus Earthlike than to just use the existing relatively Earthlike regions of the upper atmosphere to our advantage along with their unique properties. Cool off Venus and you just get a big ocean of liquid or frozen co2 to have to deal with after a loooong time and a lot of construction. Keep it like it is and a fraction of the resources/effort will yield far more utility while we can still enjoy a segment of the atmosphere.
Scifi? Of course!
Cool? Without a doubt!
Wow and then we get Lando
Venus probably doesn't have enough hydrogen to be of any use.
I've read a crazy proposal:
1. "Humidify" the atmosphere by crashing comets into Venus. This will also allow us to create a temporary "cloud" around Venus that can shield it from the Sun and lower down the temperature.
2. Once the temperature is low enough, Venus will get oceans on its surface.
3. At this point, CO2 can be split into carbon and oxygen. Oxygen will be immediately bound by the huge amount of under-oxidized iron on the surface, and carbon can be buried under the new ocean. Essentially, carboniferous age for Venus.
4. Once this is done, the atmosphere will be mostly nitrogen (at ~3 bar) and people could live there with just respirators. Eventually, once the surface iron is oxidized, the atmosphere can even be made breathable.
Apparently, this can be done within 2000-5000 years without any exotic-level engineering.
My understanding is that it was water that started the whole thing. water vapor is about ten times as effective a greenhouse gas as co2. and the runaway heat started with too much water vapor(closer to to the sun I think), leading to more heat, leading to more water vapor. eventually it got hot enough to start liberating co2 out of the rocks. leading to the current situation today where venus has way too much atmosphere.
Which is to say, putting a ring around venus to block the sun may have merit, but adding more water sounds like pouring petrol on a fire.
Water is not a driver of warming, it's an amplifier. If CO2 is removed, then the equilibrium water content will still allow Venus to be liveable.
How many comets would you have to crash and how would one redirect and crash them that wouldn't make this exotic-level?
Depending on a size, probably on the order of tens of thousand.
Comets in the Oort cloud take very little energy to put on a collision orbit, the Sun barely holds them gravitationally, orbital speeds in the Oort cloud are measured in _meters_ per second. So they require (relatively) little energy to put them into a required orbit. It might be doable with just regular thermonuclear charges.
It will then take these comets more than a thousand years to "fall" from the Oort cloud.
We'll be dead by then I'm afraid.
Venus is a damned shame. Had planetary evolution gone just slightly differently, the solar system could have had two habitable water planets. Mars, owing to its size, was never going to cut it, but Venus might have.
Crazy factoid one: The Earth masses more than everything else between the Sun and Jupiter combined.
Crazy factoid two: Venus is 80% of the Earth's mass.
It also blows my mind that the Sun accounts for 99.86% of the entire Solar System’s mass.
I wonder how a system with 2 planets with intelligent lifeforms would've developed culturally and politically... if both civilizations grew at the same rate, 2 Galileos would've looked at the other planet and figured out "we have neighbors!", but it'd be several hundred more years before communication could be done. Even know we don't have manned missions to Mars or Venus...
> a system with 2 planets with intelligent lifeforms
That is an extremely unlikely scenario because both intelligent life forms would have had to evolve before either of them developed space flight. It took homo sapiens 4 Gyr to evolve in the first place but only 100 kyr to develop space flight after that. So the odds are slim to none.
Does intelligent life mean only human-level intelligence? If we found a bunch of chimp-like animals running around, would that count as intelligent life?
Sure, but our interactions with chimp-like intelligence on another planet are unlikely to be substantially different from our interactions with chimp-like intelligence on this planet. It only gets interesting when both are more or less evenly matched, and that is extremely unlikely.
And our interactions with same-level intelligence on another planet are unlikely to be substantially different from our interactions with same-level intelligence on this planet. We've seen this before when people from one continent encountered those from another. In fiction, we show (via projection) how we might treat other intelligent life forms (every accusation is a confession).
I don't know why you'd think it'd be several hundred more years before communication could be done. If they can both observe each other, then all that's left is to devise a way to signal back visually. Seeing proof of one's neighbors would definitely drive people to develop ways to communicate, though I guess both planets would need to be similarly driven in order to establish communication.
H.G. Wells has you covered here.
Luckily we are up gravity well from them and also have a moon as a great source of low launch cost projectiles.
Using Hohmann transfer, I believe the energy cost is the same both ways. Of course as you point out we have the Moon, "they" have none. So we'd have plenty of rocks to throw.
That said, we'd have to throw much bigger rocks to penetrate their atmosphere. And the likely (to me) actual plans would be:
Us: launch to the Moon, set up there, launch rocks from the Moon to Venus.
Venusians: launch and travel to the asteroid belt, launch an asteroid toward Earth.
The more I think about it, the more I realize that our plan would be the same as theirs: we'd both be heading for the asteroid belt, because nothing we could reasonably launch from the Moon would put a dent in Venus with that atmosphere.
And if we assume they actually can launch through that atmosphere, we're screwed: if they can do that, they're way ahead of us.
Same energy to enter the orbit, but the kinetic energy per unit mass should be a whole lot higher at Venus than Earth, so each of your shots count for a lot more. But yeah, the main advantage is the moon. And you wouldn't launch things from the moon. You would launch pieces of the moon from mass drivers.
The situation I replied to assumed they were both inhabitable planets which I assume means Earth like atmosphere on Venus. The thick atmosphere complicates things, but I don't think you actually have to hit the ground. Tunguska didn't even get near the ground and it still leveled 1000 km^2. Also if Venus has the atmosphere there's no point of a war since there's no benefit to conquest in either direction.
If the Venusians had the technology to lob rocks, they'd have the technology to do so from the asteroid belt. They don't need to mine them their own non-existent moon.
Sounds delicious.
I would absolutely demolish a Venus Crust Surprise
From the headline I can't decide if it was a study in astronomy or gastronomy