Life on Venus?

[korwynkim]

Hmm. I just learned about the Martian labeled release experiment done in the 70s by the Viking landers. They took soil samples and injected nutrients tagged with Carbon-14, then monitored for evolved gas which could result from metabolism. This produced positive results with multiple samples from both landers. Control tests were done to eliminate the effect of UV-chemistry and samples were heated at different temperatures to help distinguish biology from chemistry.

Results were dismissed due to the lack of detection of organic compounds (at the time) and the lack of water, along with the result of chemical experiments carried out involving gamma ray interactions with perchlorate which could partially explain the results.

This seems like it was possibly stronger evidence of life than phosphine on Venus. I wonder how the phosphine discovery will turn out.

[korwynkim]

Some researchers went through the old Pioneer Venus mass spectrometer data and found that it probably detected phosphine: https://arxiv.org/abs/2009.12758

Others came up with a set of assumptions under which volcanism could explain the phosphine amount: https://arxiv.org/abs/2009.11904

[Guest]

Well, it's good to have more data, it suggests that phosphine is real, at least (and even in the right place, which is good). Vulcanism may be a possible explanation for why it's there, but come to think of it, we don't really know much about geology of Venus, either. I suppose we'll see a lot more reviews of the old data, it'll be a while till there'll be a new mission to check all that. Either way, that sample return mission is looking more and more interesting.

Mars is certainly looking better than Venus, but seeing as we've recently confirmed the presence of underground lakes there, it has a lot going for it either way.

[kerbiloid]

They will discover huge underground lakes of sulfic acid exhausting phosphine from dissolved venusian fishes.

[cubinator]

44 minutes ago, kerbiloid said:

They will discover huge underground lakes of sulfic acid exhausting phosphine from dissolved venusian fishes.

Venutefisk?

[Incarnation of Chaos]

Would it even be possible to construct a "Suit" that would allow someone to move on the surface? Assume we're reserved to just throwing mass at the problem at this point, since the only similar environment (pressure wise; literally nothing else) would be the bottom of the Marianas trench. And they used a thick walled steel sphere to survive that descent. You'd also need some form of air conditioner/heat exchanger/acid neutralizer/literally hell to slightly annoying conversion magic spell box to keep a passable environment. And then powering all of it; you'd probably just need to be tethered to a vehicle with some way to generate it's own power. 

Main reason I'm curious is that I've seen multiple suggestions for a manned mission already, and if anything goes wrong doomed doesn't even describe how **** they would be (Though with CO2 levels so high, they could just vent the capsule to ambient and let Hypoxia and eventual asphyxiation kill them well before hitting the gnarliest bits). I'd honestly be amazed if you could pull it off with anything short of a powered exoskeleton, but that's just me.

[kerbiloid]

The suit would be nearly spherical, weight several tons and roll on wheels.

Btw, the Venusian pressure is just about 1 km of our ocean depth, far from the Mariana trench.

Edited October 2, 2020 by kerbiloid

[Scotius]

21 minutes ago, kerbiloid said:

The suit would be nearly spherical, weight several tons and roll on wheels.

Btw, the Venusian pressure is just about 1 km of our ocean depth, far from the Mariana trench.

 

Like this, only much... much heavier. And no windows

[Guest]

Nah, it would likely resemble modern atmospheric diving suits, they can already withstand similar pressures. It'd have to be reinforced a bit, and likely powered, because unlike in water, there's no buoyancy to take advantage of on Venus. 

Thermal control would be a bigger problem, and it would probably require a large power source. So it would indeed be best to tether it to a vehicle. That would also allow moving the cooling problem to the vehicle, which is another advantage. It could be a useful attachment to a Venusian rover.

Edited October 2, 2020 by Guest

[kerbiloid]

It would be like modern diving suits but reinforced, spherical, weighting several tons due to the cooling equipment, and roll on wheels.

[Guest]

It doesn't need to be spherical, the pressures on Venus are not that high. And the cooling equipment (and power) will be in a rover, though it would still weigh a few tons. Hence why it would have powered legs.

The whole point of the suit is to provide a means of going into places which a wheeled rover can't safely reach. 

[kerbiloid]

It needs to be nearly spherical to minimize heat exchange.

[Scotius]

Airgel-like substance could be used to minimize heat transfer. It could be enough for a couple of hours long activity outside of the lander. But eventually it would need active cooling. It's funny how we can deal with extreme cold better than with heat.

[kerbiloid]

A multi-layer hull (some layers strong, some layers with low heat conductivity) with active cooling by pumping liquid hydrogen between the layers.

I estimated by fingers, a ~3 m-dianeter hull with equip behind is enough to have a short (several hours long) trip around the landing place, collect the visually chosen samples and drop them into a rotary pack of meter-long cylinders after forced cooling, then have about a half-hour of inertial cooling to lift them into the ascent stage before the rover cabin gets too hot, but it requires better calculations.

[Guest]

1 hour ago, Scotius said:

Airgel-like substance could be used to minimize heat transfer. It could be enough for a couple of hours long activity outside of the lander. But eventually it would need active cooling. 

It'll need an external power source anyway, might as well run a coolant hose, too. It'd be too heavy to move around by the operator. As a bonus, there's no need to make an actively cooled suit spherical.

Extended operations on the surface will need a rover, possibly a large one, equipped with heat pumps and probably a nuclear power source to run all this. One neat trick would be to connect it to a balloon by a cooling hose, if the pump is powerful enough, you can have the actual radiator a few kilometers up, where the air is cooler. This might be easier than trying to heat pump it up to surface temperature.

[KerikBalm]

6 hours ago, Dragon01 said:

It'd have to be reinforced a bit, and likely powered, because unlike in water, there's no buoyancy to take advantage of on Venus. 

Strictly speaking, there would be buoyancy. If the inside is 1 atm, and outside is 90+, then you will have a density difference (ignoring temp and gas composition). So I looked it up, the surface density is roughly 65 kg per cubic meter, or 6.5% the density of water.

Its not huge, but its not nothing...displacing a cubic meter of venusian atmosphere gets you 65kg of buoyant force

[Guest]

It's not really comparable to water, though. Water feels more like 0G, it can fully support even a heavy suit like an ADS, if it's filled with air. Here you get a small weight relief,  movement is still basically the same as in air at 1G.

Edited October 2, 2020 by Guest

[cubinator]

Thermal regulation requires an element which can dissipate heat away from the human, or whatever you're protecting on the surface. This is an issue because the ambience is 400 degrees C, and that part needs to get hotter than that to wick heat away from anything, and then it needs to wick over 350 degrees out of a fairly large volume. That's a far greater temperature difference than cooling something from Earth ambient to absolute zero...

[Guest]

Hence my idea with a balloon.  400 degrees would require one heck of a heat pump, and I'm not even sure if that'll be feasible at all, since a heat pump can never be 100% efficient (because thermodynamics). It's difficult to build a heat pump that would run its machinery in 400 degree heat, and you can't run it at RT and have it cool itself because it would produce more waste heat than it could ever pump out. However, what you can do is pump the coolant upward, to a balloon hovering in cooler air.

[Incarnation of Chaos]

On 10/2/2020 at 6:01 AM, kerbiloid said:

The suit would be nearly spherical, weight several tons and roll on wheels.

Btw, the Venusian pressure is just about 1 km of our ocean depth, far from the Mariana trench.

I thought the surface was 90ATM of pressure?

Oh...

Wow i really underestimated how much pressure was at the bottom of the Marianas, by about 970 ATM.

On 10/2/2020 at 5:50 PM, Dragon01 said:

Hence my idea with a balloon.  400 degrees would require one heck of a heat pump, and I'm not even sure if that'll be feasible at all, since a heat pump can never be 100% efficient (because thermodynamics). It's difficult to build a heat pump that would run its machinery in 400 degree heat, and you can't run it at RT and have it cool itself because it would produce more waste heat than it could ever pump out. However, what you can do is pump the coolant upward, to a balloon hovering in cooler air.

Goodness Gracious....

That's actually loveing brilliant, and why I'm glad i came around here! I kept trying to think about how the heck you'd manage to get heat away from something like a reactor due to the extreme heat, or cool anything down for that matter...(Since we have to have a "Cold side" and a "Hot Side"...). And completely forgot that while the surface and Atmospheric pressure is absolutely hellish, it does have the advantage of making balloons much, much more viable. 

On 10/2/2020 at 8:59 AM, Dragon01 said:

Nah, it would likely resemble modern atmospheric diving suits, they can already withstand similar pressures. It'd have to be reinforced a bit, and likely powered, because unlike in water, there's no buoyancy to take advantage of on Venus. 

Thermal control would be a bigger problem, and it would probably require a large power source. So it would indeed be best to tether it to a vehicle. That would also allow moving the cooling problem to the vehicle, which is another advantage. It could be a useful attachment to a Venusian rover.

And this also allows you a pretty easy last-ditch "Bailout" plan if you get in trouble, if you designed the rover to be justttt heavy enough with the balloon + power/radiators/etc. to remain on the surface. You could have a secondary balloon, inflated either by pyrotechnics or cylinders of compressed gas that could be activated once you clamored back inside. Once inflated; it could carry you and the machinery to a slightly more hospitable layer of the atmosphere.

The more and more i read about this, and discuss this. The cooler it actually sounds to be rather honest. Everything on this thread so far really seems startlingly similar to terrestrial diving bell operations, except inverted.

[kerbiloid]

Like always, I suggest a turboexpander to quickly cool the hydrogen coolant from +480 down to -200 and return it into the cooling pipes.
While the work produced by the turboexpander use to heat the xternal CO2 from +480 up to ~+800 and exhaust like a hot torch of superhot CO2.

The rover may have a tall exhaust pipe with a gilded umbrella to deflect its thermal radiation.

Spoiler

 

[KerikBalm]

On 10/3/2020 at 12:50 AM, Dragon01 said:

Hence my idea with a balloon. ... However, what you can do is pump the coolant upward, to a balloon hovering in cooler air.

On top of that, if the ballon is linked to the surface, you will be able to make use of the wind gradient to generate power. 

Just mount some wind turbines on the balloon. Since its not floating freely in the air, but tethered to the surface, it will experience relative wind.

I just can't see exploring the surface of venus for any substantial length of time without using a balloon that gives access to the much more temperate upper atmosphere.

-I still don't think there is any life there though :p

[Terwin]

On 10/2/2020 at 3:17 PM, Dragon01 said:

Extended operations on the surface will need a rover, possibly a large one, equipped with heat pumps and probably a nuclear power source to run all this. One neat trick would be to connect it to a balloon by a cooling hose, if the pump is powerful enough, you can have the actual radiator a few kilometers up, where the air is cooler. This might be easier than trying to heat pump it up to surface temperature.

How high would the balloon need to get to reach a usable temperature, and how heavy would the working fluid+insulation for that be?

(assuming you used a series of intermediate balloons to provide support so that the tube would not need a huge amount of strength to hold it's entire mass)

[kerbiloid]

On 10/5/2020 at 3:15 PM, KerikBalm said:

-I still don't think there is any life there though :p

Venus is alive. It digests fishes in the underground vacuoles and burps with phosphine.

The atmosphere is its outer layer.

So, the planets are slow mineral infusoria, and we are parasiting on one of them.

[korwynkim]

A team including two of the original authors looked at a different spectral frequency for phosphine and found an upper bound of only 5 ppb:

https://arxiv.org/abs/2010.07817

 

Another team disagrees with a part of the methodology used for the original data analysis and says the results are invalid:

https://arxiv.org/abs/2010.09761

 

A possible detection of glycine on Venus:

https://arxiv.org/abs/2010.06211