Author Topic: Using Synthetic Lifeforms To Terraform Other Planets  (Read 1843 times)

Offline Star One

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Springing out of this article on a breakthrough in this area, I would imagine terraforming planets such as Mars could be an important use of this technology. Any thoughts?

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Now, the first living organisms to thrive with an expanded genetic code have been made by researchers in work that paves the way for the creation and exploitation of entirely new life forms.

Scientists in the US modified common E coli microbes to carry a beefed-up payload of genetic material which, they say, will ultimately allow them to program how the organisms operate and behave.

The work is aimed at making bugs that churn out new kinds of proteins which can be harvested and turned into drugs to treat a range of diseases. But the same technology could also lead to new kinds of materials, the researchers say.

In a report published on Monday, the scientists describe the modified microbes as a starting point for efforts to “create organisms with wholly unnatural attributes and traits not found elsewhere in nature.” The cells constitute a “stable form of semi-synthetic life” and “lay the foundation for achieving the central goal of synthetic biology: the creation of new life forms and functions,” they add.

https://www.theguardian.com/science/2017/jan/23/organisms-created-with-synthetic-dna-pave-way-for-new-entirely-new-life-forms

And here's the paper.

http://m.pnas.org/content/early/2017/01/17/1616443114
« Last Edit: 01/23/2017 09:28 PM by Star One »

Offline Vultur

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Re: Using Synthetic Lifeforms To Terraform Other Planets
« Reply #1 on: 01/29/2017 02:18 AM »
Interesting.

There's been other work on "synthetic genomes" (the Mycoplasma laboratorium thing published in 2010), but this new base pair thing might be new.

It sounds like the usefulness of it hasn't been demonstrated though... given that the cell's biomechanical machinery still needs to interpret the DNA to get anything out of it, what does it gain you really? Information density, I guess, but I don't think that's a limit in any biological system.

As for the more general question of using heavily engineered lifeforms for terraforming... it's highly possible. If there's even an occasional trace of liquid water in the shallow Martian subsurface, some Earth life could probably survive there unaltered.

IIRC it's been shown that some Antarctic lichens can use the Martian atmosphere to grow at Martian temperatures, the only necessity being protection from UV (which could be provided by cracks in rock, apparently, which is how some of these lichens grow naturally).

I'm not sure about water availability though...

Offline scienceguy

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Re: Using Synthetic Lifeforms To Terraform Other Planets
« Reply #2 on: 01/29/2017 04:27 AM »
Actually, the lichen Xanthoria elegans has survived the vacuum of space (including the radiation), AND survived in Martian conditions. The limiting factor was water. Mars was just too dry for the lichen to survive more than 4 days.

https://en.wikipedia.org/wiki/Xanthoria_elegans
e^(pi)i = -1

Offline Star One

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Re: Using Synthetic Lifeforms To Terraform Other Planets
« Reply #3 on: 01/29/2017 03:25 PM »
Springing out of this article on a breakthrough in this area, I would imagine terraforming planets such as Mars could be an important use of this technology. Any thoughts?

My first thought is that level of control over an organism could be used first to clean up our own atmosphere.

But there's no free ride, where does the synthetic lifeform get its energy and resources, and what is the chemical output you wish to see?

Finally, how do you shut it off?  This sort of thing would have to be released into the wild to have any appreciable impact at a terraforming scale.  How does it know when to stop?

BTW, this sort of concept has been popular with sci-fi for ages.  James Corey's "Expanse" series and Neal Asher's "Polity" series are good examples, as is the Alien series prequel "Prometheus".

Do you think there may not be enough of the right kind of things on Mars to start with for even a synthetic organism to get anywhere no matter how highly manufactured?

Offline Vultur

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Re: Using Synthetic Lifeforms To Terraform Other Planets
« Reply #4 on: 01/29/2017 10:10 PM »
My first thought is that level of control over an organism could be used first to clean up our own atmosphere.

could be used for that, but maybe not "first"... you might want to experiment on a planet without a pre-existing biosphere first...

EDIT: If you're talking about quick radical transformations (like turning Mars into an Earthlike environment), that is. But Earth doesn't and isn't likely to need anything nearly that dramatic. But still, on Earth you'd have to worry about displacing existing life. Turning the Sahara green or such might help a lot though.

Quote
Finally, how do you shut it off?  This sort of thing would have to be released into the wild to have any appreciable impact at a terraforming scale.  How does it know when to stop?

Assuming you want it to ever stop (e.g. an oxygen-producer could continue alongside the human settlement indefinitely) it could just use up its starting material and either die off or decline into low numbers.

Do you think there may not be enough of the right kind of things on Mars to start with for even a synthetic organism to get anywhere no matter how highly manufactured?

 The materials are all there - Mars has plenty of CO2, ice & minerals, and at least some nitrogen. The question is whether there's any environment currently where at least intermittent traces of liquid water are available.

Crash a comet or two into the polar caps (to liberate CO2 & H2O as well as the comet's own volatiles) and it should work. Mars is very close to the triple point of water so even a small atmospheric pressure increase greatly increases water's liquid range.
« Last Edit: 01/29/2017 10:12 PM by Vultur »

Online Steve D

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Re: Using Synthetic Lifeforms To Terraform Other Planets
« Reply #5 on: 01/30/2017 02:31 PM »
Everyone keeps talking about teraforming Mars. What about Venus? Easy to get to, thick atmosphere, plenty of water vapor. Why not send an organism to Venus to break down the CO2?

Offline Phil Stooke

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Re: Using Synthetic Lifeforms To Terraform Other Planets
« Reply #6 on: 01/30/2017 02:46 PM »
Carl Sagan has a reply to that.  Break down the carbon dioxide and you are left with a planet covered with a thick layer of carbon dust and a dubious future.

"if the scheme worked, the result would be a surface buried in hundreds of meters of fine graphite, and an atmosphere made of 65 bars of almost pure molecular oxygen. Whether we would first implode under the atmospheric pressure or spontaneously burst into flames in all that oxygen is open to question. However, long before so much oxygen could build up, the graphite would spontaneously burn back into CO2, short-circuiting the process."

Offline DarkenedOne

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Re: Using Synthetic Lifeforms To Terraform Other Planets
« Reply #7 on: 01/30/2017 03:03 PM »
Carl Sagan has a reply to that.  Break down the carbon dioxide and you are left with a planet covered with a thick layer of carbon dust and a dubious future.

"if the scheme worked, the result would be a surface buried in hundreds of meters of fine graphite, and an atmosphere made of 65 bars of almost pure molecular oxygen. Whether we would first implode under the atmospheric pressure or spontaneously burst into flames in all that oxygen is open to question. However, long before so much oxygen could build up, the graphite would spontaneously burn back into CO2, short-circuiting the process."

Not if you have an ocean.  Earth began with a CO2 atmosphere like Venus.  Plant life eventually consumed the CO2 releasing O2 in the process.  Of course in the ocean the microorganisms would die and fall to the bottom.  It is definitely conceivable that the same process that Earth went through can occur on Venus. 

The real problem is that the heat I think prevents any life from getting a foot hold.

Honestly I think that Venus has more potential to be an alternative home for humanity than Mars.  It has about the same gravity.  It is just 25% closer to the sun.   

Online Steve D

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Re: Using Synthetic Lifeforms To Terraform Other Planets
« Reply #8 on: 01/30/2017 03:40 PM »
It wouldn't be powdered graphite, it would be hydrocarbons left over from the dead organisms.  And wouldn't the oxygen start to react with other elements on Venus? Surface pressure is around 90 atmospheres right now. Wouldn't removing the carbon dioxide greatly drop the pressure?
« Last Edit: 01/30/2017 03:45 PM by Steve D »

Offline Star One

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Re: Using Synthetic Lifeforms To Terraform Other Planets
« Reply #9 on: 03/09/2017 07:00 PM »
And here you have it another step towards our ability to construct scratch built artificial life forms. And I have to feel if we ever want to colonise other planets this is one of the technologies we will need.

http://gizmodo.com/scientists-just-took-a-major-step-toward-the-first-comp-1793106676

Offline quanthasaquality

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Re: Using Synthetic Lifeforms To Terraform Other Planets
« Reply #10 on: 03/10/2017 12:37 AM »
Yeah, that 'synthetic life' is not a big difference from current earth life. Earth life is carbon, nitrogen, and water based, which limits the conditions it can exist under. It can go a bit below 0 celsius in salt water. I guess the upper limit could be around 150 celsius, where biomolecules cook here on earth. The actual upper limit is probably going to be lower than that. Now if 'synthetic life' was something weird, like carbon, and ammonia based, or silicon based, there could be real applications.

I guess much of the carbon dioxide could be sequestered on Venus into carbonate rocks, but Venus still needs lots of hydrogen. As for Mars, life on Earth requires a lot of water. The Sahara desert technically has life, but only a small fraction of its surface is covered with plants.

Offline KelvinZero

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Re: Using Synthetic Lifeforms To Terraform Other Planets
« Reply #11 on: 03/10/2017 06:13 AM »
Carl Sagan has a reply to that.  Break down the carbon dioxide and you are left with a planet covered with a thick layer of carbon dust and a dubious future.

"if the scheme worked, the result would be a surface buried in hundreds of meters of fine graphite, and an atmosphere made of 65 bars of almost pure molecular oxygen. Whether we would first implode under the atmospheric pressure or spontaneously burst into flames in all that oxygen is open to question. However, long before so much oxygen could build up, the graphite would spontaneously burn back into CO2, short-circuiting the process."
We discussed an idea for this somewhere a while back.. I think it was inspired from a scene from interstellar.

For venus, I imagine a sort of self reproducing foam bubble. It breeds high in the atmosphere where conditions are roughly earthlike. It contains a lighter than air gas which could be almost anything on Venus. It might be breathable air or hydrogen painstakingly extracted from the surroundings, so that inside the membrane of each bubble we can do normal chemistry with the usual CHON elements. Another option is Nitrogen and water vapor which could make the foam a fire retardant overall.

If this bubble creature could breed exponentially it could soon cover venus in a massive aerogel-like layer, effectively creating a new surface that could perhaps rotate faster than the underlying solid planet. Although the foam itself could be very fragile a km-thick layer could easily support a hard surface.

If exponential growth caused this to eat the entire atmosphere, perhaps you could arrange all the pure carbon to be sequestered beneath a chalk-like layer?

Offline Star One

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Re: Using Synthetic Lifeforms To Terraform Other Planets
« Reply #12 on: 03/10/2017 07:24 AM »
Yeah, that 'synthetic life' is not a big difference from current earth life. Earth life is carbon, nitrogen, and water based, which limits the conditions it can exist under. It can go a bit below 0 celsius in salt water. I guess the upper limit could be around 150 celsius, where biomolecules cook here on earth. The actual upper limit is probably going to be lower than that. Now if 'synthetic life' was something weird, like carbon, and ammonia based, or silicon based, there could be real applications.

I guess much of the carbon dioxide could be sequestered on Venus into carbonate rocks, but Venus still needs lots of hydrogen. As for Mars, life on Earth requires a lot of water. The Sahara desert technically has life, but only a small fraction of its surface is covered with plants.

Well the debate seems to be in the longer term whether it's going to be cheaper and more useful to scratch build lifeforms or to edit the existing ones to the way you want them.

Offline IRobot

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Re: Using Synthetic Lifeforms To Terraform Other Planets
« Reply #13 on: 03/10/2017 08:20 AM »
Everyone keeps talking about teraforming Mars. What about Venus? Easy to get to, thick atmosphere, plenty of water vapor. Why not send an organism to Venus to break down the CO2?
How about doing the reverse of proposed Mars magnetic field generator? Could we create a magnetic field that, interacting with Venus magnetic field would maximize the effect of solar wind, ripping the upper atmosphere?

This could be combined with an organism that would break down the atmosphere into lighter gas, so it would expand.

Offline Rei

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Re: Using Synthetic Lifeforms To Terraform Other Planets
« Reply #14 on: 03/20/2017 03:23 PM »
Carl Sagan has a reply to that.  Break down the carbon dioxide and you are left with a planet covered with a thick layer of carbon dust and a dubious future.

"if the scheme worked, the result would be a surface buried in hundreds of meters of fine graphite, and an atmosphere made of 65 bars of almost pure molecular oxygen. Whether we would first implode under the atmospheric pressure or spontaneously burst into flames in all that oxygen is open to question. However, long before so much oxygen could build up, the graphite would spontaneously burn back into CO2, short-circuiting the process."

I strongly disagree with Sagan's assessment, for one key reason.

The length of time for such terraforming has been estimated at between tens of thousands to millions of years.  You don't just instantly end up with some giant pile of carbon and huge amount of oxygen; it's a slow process.  Venus's surface contains large amounts of FeO (upper single digits percent).  Under Venus's extreme surface conditions, this will oxidize almost immediately with even tiny amounts of oxygen (ultimately up to Fe2O3).  Oxygen doesn't accumulate - at least at first.  It rusts the surface.

The exact same thing happened on Earth; that's what the banded iron deposits are. When Earth lifeforms started accumulating carbon biomass and generating oxygen, did Earth turn into some giant explosion-in-waiting?  Of course not.  Carbon from  primitive autotrophs was sequestered in along with the huge amounts of rust they were generating, locking it up in the crust.  The exact same thing should happen on Venus (with the difference that on Earth the rusting primarily happened in the oceans, while on Venus it would be the surface).  Rust erodes away.  Venus's winds are slow, but the density means that they still have significant power to move dust.  Its characteristic dune sizes are much smaller than on Earth (more like oceanic sand ridges), but it does blow things around, and has even sculpted yardangs.  Iron rusts preferentially to carbon, dust blows it away, mixes it with precipitating carbonaceous matter, accumulates in low points, and continues to be buried until it compacts into sedimentary rock (no subduction on Venus, though).

Oxygen can only build up when things that it is significantly reactive with have been consumed.  Like on Earth, once the FeO and other under-oxidized compounds start to disappear, then you can start to accumulate oxygen in the atmosphere. But not before then.
« Last Edit: 03/20/2017 03:50 PM by Rei »

Offline Rei

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Re: Using Synthetic Lifeforms To Terraform Other Planets
« Reply #15 on: 03/20/2017 03:30 PM »
As for general viability of the idea, it's hard to say. Of the basic components of Earth life - CHONPS - C and O are extremely abundant, N and S moderately abundant, H rare but present, and P would best be described as "probably detected, theoretically moderately abundant, but poorly quantified, and altitude-dependent". It's been argued that the lower cloud layer is primarily majority phosphoric acid and related compounds - but our knowledge of Venus's atmosphere is sadly very poor.  Another element often used by life, iron, is also surprisingly found (under the same caveats as phosphorus) in the clouds in the form of ferric chloride, at an abundance somewhere around 1% as common as sulfuric acid.  Chlorine itself is pretty common too, mainly as anhydrous hydrogen chloride. Alkali and alkaline cations however are probably not present in any relevant quantities.

The big problems for life are the relative rarity of hydrogen-bearing compounds (primarily locked up in acids and anhydrous acidic gases), and the extremely hygroscopic, acidic environment. It might be possible to make something that could survive there, but it'd be pushing up against the edges of what life might be able to achieve.
« Last Edit: 03/20/2017 03:48 PM by Rei »

Offline Rei

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Re: Using Synthetic Lifeforms To Terraform Other Planets
« Reply #16 on: 03/20/2017 03:37 PM »
How about doing the reverse of proposed Mars magnetic field generator? Could we create a magnetic field that, interacting with Venus magnetic field would maximize the effect of solar wind, ripping the upper atmosphere?

This could be combined with an organism that would break down the atmosphere into lighter gas, so it would expand.

Any of the proposals for "ripping away" or "ejecting" or "sequestering" Venus's atmosphere suffer from the inverse of the iron problem above: once you start making oxygen, it's going to start rusting the planet and be lost. You really need the oxygen from the CO2 in the atmosphere... or if not it, then at least some crustal source.

That said, the solar wind is interesting from a different aspect: it's mostly hydrogen, and that's the hardest thing to get to Venus. I've not seen any studies on the topic, so its pure speculation, but if a system could be designed to decelerate solar wind to Venus capture, it might be a solution to that problem (without hydrogen, Venus will be a desert world... hydrogen is to it what nitrogen is to Mars, one of the tougher stumbling blocks to overcome if you want life to become abundant).  It's pretty easy to demonstrate that you're not going to supply hydrogen quickly from the solar wind, but if you're talking on the scale of the tens of thousands to millions of years phototrophs would need to sequester the atmosphere, it might be plausible.

The other big issue, its slow rotation rate, is probably easiest just to deal with via soletta to mimic a shifting day/night cycle; the amount of energy needed to actually change the planet's rotation rate is insane.  Well, at least giving Venus an Earthlike rotation wouldn't be as hard as giving Mars Earthlike gravity, but on the order of insanely difficult things to accomplish, it's up there.
« Last Edit: 03/20/2017 03:51 PM by Rei »

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