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The phosphorus problem: how severe is it?

puskas78

puskas78

Phosphorus shortage may make alien life very rare

TL;DR some regions in space contain a very little phosphorus. This could hinder the natural development of life, because ATP and nucleic acids contain phosphorus.

The article says that phosphorus is scarce in some regions, not completely absent.

While this could mean that there are fewer alien biospheres out there, it doesn't mean that life (as we know it) couldn't exist on planets formed in these regions. If phosphorus is too rare for life to develop on its own but not completely absent, then colonists could "mine" it for the closed biospheres of the colonies.

This would make establishing a colony on an alien planet much more difficult, but not impossible.
 
Are there other chemicals that exotic life could use instead of ATP and nucleic acids? Life need not neccessarily work the way it does here, after all.
 
Zap Rowsdower said:
Are there other chemicals that exotic life could use instead of ATP and nucleic acids? Life need not neccessarily work the way it does here, after all.
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Yes, but they are way worse for that job. That's why carbon, water and phosphorus are so important: they do have other chemicals to replace them, but they are the definite best from chemical point of view to create life. Nothing else comes close.
 
Zap Rowsdower said:
Are there other chemicals that exotic life could use instead of ATP and nucleic acids? Life need not neccessarily work the way it does here, after all.
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I think that this is more realistic than life based on silicon and similar things. I'm not sure about a possible replacement for ATP, but genes? Does data storage (this is what nucleic acids do) really depend on some specific chemical property? Could transcription factors and ribosomes "read" a different "data format" from a different "storage medium" for protein synthesis?
 
puskas78 said:
Phosphorus shortage may make alien life very rare

TL;DR some regions in space contain a very little phosphorus. This could hinder the natural development of life, because ATP and nucleic acids contain phosphorus.

The article says that phosphorus is scarce in some regions, not completely absent.

While this could mean that there are fewer alien biospheres out there, it doesn't mean that life (as we know it) couldn't exist on planets formed in these regions. If phosphorus is too rare for life to develop on its own but not completely absent, then colonists could "mine" it for the closed biospheres of the colonies.

This would make establishing a colony on an alien planet much more difficult, but not impossible.
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I guess we just won't find many aliens in those regions?

We could just look elsewhere...
 
Given that we have exactly one example of life to examine, I wouldn't be too firmly attached to the idea that all life has to work just like our kind does.

Also after some googling there's apparently at least one exception here on Earth to life needing phosphorus.

Researchers conducting tests in the harsh environment of Mono Lake in California have discovered the first known microorganism on Earth able to thrive and reproduce using the toxic chemical arsenic. The microorganism substitutes arsenic for phosphorus in its cell components.

"The definition of life has just expanded," said Ed Weiler, NASA's associate administrator for the Science Mission Directorate at the agency's Headquarters in Washington. "As we pursue our efforts to seek signs of life in the solar system, we have to think more broadly, more diversely and consider life as we do not know it."
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Avernus said:
Given that we have exactly one example of life to examine, I wouldn't be too firmly attached to the idea that all life has to work just like our kind does.

Also after some googling there's apparently at least one exception here on Earth to life needing phosphorus.
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TL;DR uses arsenic instead of phosphorus. Arsenic is more rare, if even phosphorus is rare on an alien planet, then don't expect much arsenic to be around.
 
This whole thing comes off as a bit stupid. Assuming that life will be like our life is foolish, assuming life will be constructed like us is foolish.
 
Download said:
This whole thing comes off as a bit stupid. Assuming that life will be like our life is foolish, assuming life will be constructed like us is foolish.
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Not really. It's stupid to think life can ONLY be like us, sure, but it's even stupider to think that it will be completely different.

Life is made of the simplest parts, not the most complicated.

Take Silicon Life, for example. Theoretically possible, maybe, but even if it is, there would probably be FAR more carbon based life simply because carbon is more abundant.
 
When it comes to the search of life, I do wonder how to quantify terms like "rare" or "abundant" without a proper reference. While we have earth's biosphere, I wonder how an optical spectrum of earth or the solar system would look like from 10 light years away. Now add that the elemental composition/distribution of the original proto disc or the original super nova also probably looked different.

Science is hard......
 
Cloak&Dagger said:
Not really. It's stupid to think life can ONLY be like us, sure, but it's even stupider to think that it will be completely different.

Life is made of the simplest parts, not the most complicated.

Take Silicon Life, for example. Theoretically possible, maybe, but even if it is, there would probably be FAR more carbon based life simply because carbon is more abundant.
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It's a bit more nuanced than this. Yes, at a glance, Carbon is more abundant in the universe than Silicon (4 600 : 650 PPM(Mass)). And this goes for our solar system as well (3 032 : 653 PPM(Mass)).

On Earth, however, Silicon is far more abundant than Carbon (730 : 161 000 PPM(Mass)).

So, given their relative abundances, it would seem more likely to have Silicon based lifeforms rather than Carbon based ones. Except that Silicon is pretty terrible at forming covalent bonds with itself, something which severely limits its ability to form complex molecules. Carbon, on the other hand, readily forms single, double and triple bonds with itself.
This versatility of Carbon is what makes it far superior at forming complex compounds. And this versatility, not its apparent abundance, is what makes it the element of choice at forming (at least our complex compound based) life.

So, just because Phosphorus is generally relatively scarce in a certain region, this does not mean that there will be a shortage for the formation of life. There could be planets with a ar greater abundance of Phosphorus present than the region might suggest (in the same way Silicon is far more abundant on Earth than its region, the solar system, might suggest).

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Other than that, I agree. To quote Ian Malcolm: "Life, uh, finds a way". Phosphorus is probably not absolutely necessary for life to form (although it might still be pretty convenient to have around).

On the colonization angle, I expect even the low abundance regions to have enough Phosphorus to sustain human life. I haven't done the math, but I suspect that even here on Earth most of the Phosphorus is in the form of mineral deposits. The same would probably go for other planets, which would require it to be liberated from those minerals, but this would only make colonization a bit more expensive.
 
Shimrod said:
, it would seem more likely to have Silicon based lifeforms rather than Carbon based ones. Except that Silicon is pretty terrible at forming covalent bonds with itself, something which severely limits its ability to form complex molecules. Carbon, on the other hand, readily forms single, double and triple bonds with itself.
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The behavior of the oxides in Earth's surface conditions (reactive gas and almost completely inert solid) is also important...

Shimrod said:
On the colonization angle, I expect even the low abundance regions to have enough Phosphorus to sustain human life. I haven't done the math, but I suspect that even here on Earth most of the Phosphorus is in the form of mineral deposits. The same would probably go for other planets, which would require it to be liberated from those minerals, but this would only make colonization a bit more expensive.
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Human life needs a lot of phosphorus for the bones:
Bone - Wikipedia
The inorganic composition of bone (bone mineral) is primarily formed from salts of calcium and phosphate, the major salt being hydroxyapatite (Ca10(PO4)6(OH)2).[18] The exact composition of the matrix may change over time and with nutrition, with the ratio of calcium to phosphate varying between 1.3 and 2.0 (per weight), and trace minerals such as magnesium, sodium, potassium and carbonate also being found.[18]
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