Exobiology/xenoscience

[Johnny Pneumatic]

Welcome to the discussion of alien life.:)

First off, what about a life form that has one end in sunlight and the other end in shadow, setting up an electric current that fuels it instead of it eating or using photosynthesis?

[Yaotl]

Originally posted by SkepticJ
Welcome to the discussion of alien life.:)

First off, what about a life form that has one end in sunlight and the other end in shadow, setting up an electric current that fuels it instead of it eating or using photosynthesis?


How would it set up the electric current?

[Johnny Pneumatic]

Originally posted by Yaotl
How would it set up the electric current?

Perhaps it could work like a PV cell.

[Yaotl]

Originally posted by SkepticJ
Perhaps it could work like a PV cell.

I don't understand how those work (yes, I did Google it, but I don't understand it), but let's assume that's the case. Is there anything out there that converts energy into matter? Googling that doesn't turn up anything practical.

[Johnny Pneumatic]

Originally posted by Yaotl
I don't understand how those work (yes, I did Google it, but I don't understand it), but let's assume that's the case. Is there anything out there that converts energy into matter? Googling that doesn't turn up anything practical.

Why would it need to create matter? Plants don't. They use the energy from the sun to put together organic molecules that they and heterotrophes eat plants or other heterotrophes. Basically I'm trying to put forth an idea which isn't mine and see if it's plausible. After this maybe we could then move into the chemistry of alien life. The chemical arrangement we have can't be close to all their is.

[Soapy Sam]

Larry Niven's Outsiders.

Hey- you read "Ringworld". Your mind is going.

[Yaotl]

Originally posted by SkepticJ
Why would it need to create matter? Plants don't. They use the energy from the sun to put together organic molecules that they and heterotrophes eat plants or other heterotrophes. Basically I'm trying to put forth an idea which isn't mine and see if it's plausible. After this maybe we could then move into the chemistry of alien life. The chemical arrangement we have can't be close to all their is.

How don't plants create matter? Do they not grow and reproduce? Something that would only use the sun as food wouldn't be taking in anything else, correct? Where would it get anything it needs to grow or reproduce from?

[Johnny Pneumatic]

Originally posted by Yaotl
How don't plants create matter?

How long has it been since you took biology? Plants don't create matter from energy. They use the energy input from the sun to put molecules together to store energy. We eat plants and animals to get this potential energy to run, we're fighting entropy. We break the molecules down taking their potential energy, poop them out and plants put the chemicals back together again. Over and over again. Until the sun grows into a red giant and boils away the oceans there will be life on earth.

[Yaotl]

Originally posted by SkepticJ
How long has it been since you took biology? Plants don't create matter from energy. They use the energy input from the sun to put molecules together to store energy. We eat plants and animals to get this potential energy to run, we're fighting entropy. We break the molecules down taking their potential energy, poop them out and plants put the chemicals back together again. Over and over again. Until the sun grows into a red giant and boils away the oceans there will be life on earth.

Sorry, that should have been "How don't plants create matter from matter?" As in, they still "eat" in a sense.

[Johnny Pneumatic]

Originally posted by Soapy Sam
Larry Niven's Outsiders.

Hey- you read "Ringworld". Your mind is going.

Hey I have the disclaimer already on here. I don't steal. Mind going?

[phildonnia]

Originally posted by Yaotl
How don't plants create matter? Do they not grow and reproduce? Something that would only use the sun as food wouldn't be taking in anything else, correct? Where would it get anything it needs to grow or reproduce from?

Plants take in water and carbon-dioxide, and this is turned into cellulose. The solar energy provides energy for the series of chemical reactions that does this.

A pure-sunlight plant could work perhaps like this: Solar energy consists of photons which have been known to break into matter-antimater pairs. If these could be separated, (through some machine that also consumes solar energy??) then atoms and molecules and stuff could be built from this.

But I think it would take a crapload of energy to pull this off.

[Johnny Pneumatic]

Originally posted by Yaotl
Sorry, that should have been "How don't plants create matter from matter?" As in, they still "eat" in a sense.

Then by your definition these PV beings eat light.

[Yaotl]

Originally posted by SkepticJ
Then by your definition these PV beings eat light.

Through photosynthesis? I just don't understand how it could live off of purely light.

[Johnny Pneumatic]

Originally posted by phildonnia
A pure-sunlight plant could work perhaps like this: Solar energy consists of photons which have been known to break into matter-antimater pairs. If these could be separated, (through some machine that also consumes solar energy??) then atoms and molecules and stuff could be built from this.

How can they split? I thought photons were their own antiparticle.

[Johnny Pneumatic]

Epona Project (http://www.eponaproject.com/)
Looks like they beat me to the idea of mushroom trees, maybe. Their's don't look like mine.

[Johnny Pneumatic]

I found another new neat site just now. http://www.contact-conference.com/

[phildonnia]

Originally posted by SkepticJ
How can they split? I thought photons were their own antiparticle.

"Split" was perhaps an over-evocative word choice. I believe the technical term is "couple."

The photon disappears entirely, and an electron-positron pair appears, for example.

[Xeriar]

Originally posted by SkepticJ
Welcome to the discussion of alien life.:)

First off, what about a life form that has one end in sunlight and the other end in shadow, setting up an electric current that fuels it instead of it eating or using photosynthesis?

It still needs something to grow with though. As far as I know, actual energy absorbtion isn't that different between chloroplasts and PV cells - photon strikes exciteable molecule, activates electron, electron goes on its way.

Many different pigments are possible though, and it certainly isn't necessary for plants to be green.

Regardless, in order to be called life it's going to have to grow or reproduce after some fashion. This means stripping carbon out of the surrounding environment - probably either methane or CO2.

Methane does not seem to me like a suitable solution unless we're talking about a planet with 5 times Earth's gravity to keep escaped hydrogen in.

[Johnny Pneumatic]

Originally posted by phildonnia
"Split" was perhaps an over-evocative word choice. I believe the technical term is "couple."

The photon disappears entirely, and an electron-positron pair appears, for example.

Weird. How? Now here are a few ideas I came up with.

Imagine an animal that looks kind of like a wood louse(a.k.a. pill bug) from a distance because it has overlapping aerogel (http://www.sti.nasa.gov/tto/spinoff2001/ch5.html) plates. It lives in extrem(compared to earth) arctic conditions. It doesn't have to eat because it has a symbiotic relationship with algae-like organisms. It's a completely closed system except for light, like those glass spheres with water an shrimp. The algae are insulated against the cold and the "exo pill bug" never has to eat or drink. The algae use its waste including its watery urine, CO2 from its cellular respiration and sunlight to photosynthesize. The animal only moves to keep out of shadows and when they mate for the only time in their 4,400 year life span. They aren't even close to sentient by the way.

[Xeriar]

Originally posted by SkepticJ
Imagine an animal that looks kind of like a wood louse(a.k.a. pill bug) from a distance because it has overlapping aerogel (http://www.sti.nasa.gov/tto/spinoff2001/ch5.html) plates. It lives in extrem(compared to earth) arctic conditions. It doesn't have to eat because it has a symbiotic relationship with algae-like organisms. It's a completely closed system except for light, like those glass spheres with water an shrimp. The algae are insulated against the cold and the "exo pill bug" never has to eat or drink. The algae use its waste including its watery urine, CO2 from its cellular respiration and sunlight to photosynthesize. The animal only moves to keep out of shadows and when they mate for the only time in their 4,400 year life span. They aren't even close to sentient by the way.

Aerogel begins to collapse with too much moisture. Not that something similar won't work.

It needs to have a larval stage of some sort, I think, if it's going to reproduce. Some way to make new bugzies.

I think phildonnia was talking about quantum vacuum fluctuations? I didn't think they require photons...

[Johnny Pneumatic]

Originally posted by Xeriar
Aerogel begins to collapse with too much moisture.


I don't know what "aerogel" you're talking about; aerogel is water proof, at least I thought so.....
Perhaps you're thinking of "seagel"?

[Xeriar]

Originally posted by SkepticJ
I don't know what "aerogel" you're talking about; aerogel is water proof, at least I thought so.....
Perhaps you're thinking of "seagel"?

No, I was thinking of earlier gels that could not be made with or around water. There are lots of different kinds.

http://www.aerogel.com/literature.htm

Is an interesting resource.

[Johnny Pneumatic]

What of bones made from stuff other than calcium? Metal alloys for example, perhaps in the form of open celled metal foams? What of claws or "horns" made of metal alloys? Or....dare I utter a reference to carbon nanotubes............? Damn, just did! :biggrin:

[Xeriar]

Originally posted by SkepticJ
What of bones made from stuff other than calcium? Metal alloys for example, perhaps in the form of open celled metal foams? What of claws or "horns" made of metal alloys? Or....dare I utter a reference to carbon nanotubes............? Damn, just did! :biggrin:

I'm kind of curious as to what kind of evolution would bring about nanotubes. If, by some unheard-of enzyme, a cell could form its shell out of C2 carbon bonds, then it'd be the kind of the hill. But it'd have to form it.

Titanium bones could be interesting, though I think we use calcium because mechanisms for handling magnesium required us to do -something- with calcium, just because it got common. Titanium, on the other hand, is safe to ignore.

[Johnny Pneumatic]

Originally posted by Xeriar
I'm kind of curious as to what kind of evolution would bring about nanotubes. If, by some unheard-of enzyme, a cell could form its shell out of C2 carbon bonds, then it'd be the kind of the hill. But it'd have to form it.

I thought up a six legged turtleish animal with a nanotube shell a few weeks back, and something that would make a predator basically unstoppable....but I'm not telling.:p

[Xeriar]

Originally posted by SkepticJ
I thought up a six legged turtleish animal with a nanotube shell a few weeks back, and something that would make a predator basically unstoppable....but I'm not telling.:p

I sometimes wonder if a species might place its heart, brain or other organ that generates a magnetic field such that it might actually power a sort of biological moter.

So you have living cars running around :p

[Johnny Pneumatic]

I take the smilely as meaning you know the fields made by those are to weak to do anything like that by orders of magnitude.

[Xeriar]

Originally posted by SkepticJ
I take the smilely as meaning you know the fields made by those are to weak to do anything like that by orders of magnitude.

For us, yes, but for something a lot smaller than us that for some reason developed much stronger fields, I don't find it much less plausible than a biological process making nanotubes.

Our heart only generates a field of several dozen picotesla, but muscles can generate a lot of electrical power if they are put to the task, however.

For me the joke is what would develop spinning.

[Johnny Pneumatic]

Originally posted by Xeriar
For me the joke is what would develop spinning.

Soapy Sam had some ideas on this, I'll let him tell you so I don't screw up the description.

This is an oldie of mine. What do you make of it? http://randi.org/vbulletin/attachment.php?s=&postid=1870551971

I had pictured these clogging the sky of a planet. Small flying animals that could reach them speciated and there is a full ecology going on. The aniamls are pretty small obviously. Probably the top predator isn't much larger than a spider monkey. Perhaps they are connected into vast mats/clusters in the sky by tough vine like "runners" Other plants grow on the gas plants for food for the small arthropods to feed on as the second step in the food chain.

[Xeriar]

Originally posted by SkepticJ
This is an oldie of mine. What do you make of it? http://randi.org/vbulletin/attachment.php?s=&postid=1870551971

I had pictured these clogging the sky of a planet. Small flying animals that could reach them speciated and there is a full ecology going on. The aniamls are pretty small obviously. Probably the top predator isn't much larger than a spider monkey. Perhaps they are connected into vast mats/clusters in the sky by tough vine like "runners" Other plants grow on the gas plants for food for the small arthropods to feed on as the second step in the food chain.

I think it would look more like a funnel to collect more sunlight and water. I don't think it'd have an H2 release valve. The clearest way I see that evolving is somehow developing a way to store 'unneeded' hydrogen, either macroscopically or inside cells. When it needs it, it starts burning hydrogen with the surrounding oxygen to make water. For energy generation and, perhaps, for propulsion.

This has several benefits - releasing H2 like that will quickly deplete the world's water, and even more quickly depleting -their- water, which they only get from rain and ambient moisture. So not only will making use of that hydrogen possibly lead to living jets, it's the sustainable way to go :-)

Potentially very cool. A warm planet with a thick atmosphere and lots and lots of rainfall.

[phildonnia]

Originally posted by SkepticJ
Weird. How? Now here are a few ideas I came up with.


Now mind you, I don't understand this, I'm just mentioning that it's possible.
http://en.wikipedia.org/wiki/Pair_production

[wollery]

Originally posted by phildonnia
Now mind you, I don't understand this, I'm just mentioning that it's possible.
http://en.wikipedia.org/wiki/Pair_production Yeah, you can make electron-positron pairs easily enough, but you would also need to make proton-antiproton pairs, and have you any idea how much energy is required to do that? It requires the collision, at high velocity, of an electron-positron pair (which doesn't guarantee the right result), or the collision of two very high energy photons (again, no guarantee of proton-antiproton pair). They do it regularly at CERN, but how would a plant or animal produce that kind of effect?

[Johnny Pneumatic]

This idea I "stole" from nature. Fan-like alien plants that live on the ocean floor relativly close to geothermal vents. How do they survive you ask, there's no light? Oh yes their is, IR light. On Earth there are microrganisms down near these vents that use this to power their photosynthesis instead of the light we can see which doesn't exist there.

What of an alien animal that lifts about 95% of its weight using a hydrogen gas bag. It generates the rest of its lift and thrust with a pair of wings. It has four grabber arms with sharp hooked claws that it uses to attach itself to something when at rest so it doesn't blow away.

[TillEulenspiegel]

Originally posted by SkepticJ
This idea I "stole" from nature. Fan-like alien plants that live on the ocean floor relativly close to geothermal vents. How do they survive you ask, there's no light? Oh yes their is, IR light. On Earth there are microrganisms down near these vents that use this to power their photosynthesis instead of the light we can see which doesn't exist there.

What of an alien animal that lifts about 95% of its weight using a hydrogen gas bag. It generates the rest of its lift and thrust with a pair of wings. It has four grabber arms with sharp hooked claws that it uses to attach itself to something when at rest so it doesn't blow away.

It's been done. I don't recall the name or author ( Niven maybe?) but it had huge gasbags that used the currents in Jupiter's atmosphere to get around . It also had predators called sharks that ate the gasbags.

There is a difference between Photosynthesis and the photo-voltaic effect. Einstein (who else? ) explained it . The incoming photon causes the atom it strikes in the PV cell to elevate the orbit or energy level of an electron in it's outer orbit , the electron then drops back to it's intrinsic state. The excess energy expressed is carried away as a current.

Thats fine but any growth in any real animal must have raw material to draw upon. An electric eel consumes food and uses it as a source of it's electrical generator - kind of biological battery. That is a chemical reaction. The photosynthesis of a plant uses the sun but also water and nutrients from the soil to grow. The direct transformation of energy to matter is just impossible and a bad SF road to travel.

Your idea of a symbiotic relationship is more plausible say where organism 1 is able to absorb light and express it as heat. The secondary organism uses the heat to enable it to convert the matter it consumes (gasses, water, whatever) and it's waste is the food of the primary organism.

[Johnny Pneumatic]

Originally posted by TillEulenspiegel
It's been done. I don't recall the name or author ( Niven maybe?) but it had huge gasbags that used the currents in Jupiter's atmosphere to get around . It also had predators called sharks that ate the gasbags.

The direct transformation of energy to matter is just impossible and a bad SF road to travel.

New ideas must be nearly impossible now. No matter we're just talking about what could evolve, not something for a story.

How so? I thought E=MC squared? In fission, atomic nuclei are destroyed and energy is released. Why not the opposite?

[wollery]

Originally posted by SkepticJ
New ideas must be nearly impossible now. No matter we're just talking about what could evolve, not something for a story.

How so? I thought E=MC squared? In fission, atomic nuclei are destroyed and energy is released. Why not the opposite? It's the amount of energy required that prevents it. As I posted above, it's easy to make electrons/positrons, you only need gamma radiation. Making protons/antiprotons and neutrons/antineutrons requires the direct collision of two extremely high energy photons, or an electron-positron pair. We need a massive particle accelerator like CERN to do it. If you can design a biological system that can do that without being destroyed itself then more power to ya.

[Larspeart]

Ah yes. This goes back to the old 'what IS 'Life'' arguement.

Lemme put it this way. I put a stone in front of you. I ask you to PROVE to me that this is NOT alive. I stitulate that perhaps it is just living, growing, dying, reproducing so slowly that you simply can not see it happen.

Or, I put a wristwatch in front of you. it shows rhythm, movement, order. it consumes energy. it produces waste. Prove that it isn't alive.

[TillEulenspiegel]

Well it's not a suitable story line. Einstein did show that matter and energy are equivalent but we can only do fission , which is pretty destructive. Fusion is less destructive and converts and synthesizes one element from another , so your talking about a walking atom bomb or a mini sun. Neither one is practical or believable especially when there are acceptable working scenarios.

[phildonnia]

Just to be clear, it's misleading to speak of "transforming energy into matter". They are the same thing. Although it's fine to dispute the feasability of converting photons into atoms.

Even if we accept the artificial "atoms = matter, photons = energy", it is misleading to say that nuclear reactions convert matter into energy. Not one single neutron is converted in this way in a nuclear reaction.

The only reason nuclear reactions got associated with E=mc^2 is that this equivalence was once used as a guesstimate of the energy from a nuclear reaction. But its not specific to nuclear reactions. Burning a piece of wood will convert lose a (very) small amount of mass, representing the energy of the chemical bonds.

[Xeriar]

Originally posted by TillEulenspiegel
It's been done. I don't recall the name or author ( Niven maybe?) but it had huge gasbags that used the currents in Jupiter's atmosphere to get around . It also had predators called sharks that ate the gasbags.

Arthur C. Clarke's 2010, actually.

[chance]

SkepticJ First off, what about a life form that has one end in sunlight and the other end in shadow, setting up an electric current that fuels it instead of it eating or using photosynthesis? This is the principle of a thermocouple, two strands of dissimilar metal joined at both ends, heating one end only will induce a small current to flow, the load is in series with one of the strands. Currently used in high temperature measuring instruments. I don’t think there is a biological equivalent.

A plant could make use of this type of arrangement the roots would be at a different temperature to the leaves.

[Soapy Sam]

Reading the thread just triggered a bizarre notion of vast, low pressure, organic steam engines- living in a rarified atmosphere, generating steam by internal metabolic heat, assisted by partial vacuum generated by a muscular gut that acts as an air pump.

Big, floppy, muscular valves in the circulatory system... motive power would be a problem- reaction jets? They might communicate chemically, by fart codes or enzyme doped flatulence.

MY mind is going. I can feel it...

[Johnny Pneumatic]

Originally posted by Soapy Sam
MY mind is going. I can feel it...

Daisy..., Daisy, Give me your answer to. I'm half crazy, all for the love of you.....

[Soapy Sam]

It was the slow Doppler drop in pitch of HAL's voice that made my hair stand on end...few death scenes in movies made such an impression.

[Johnny Pneumatic]

Originally posted by Soapy Sam
It was the slow Doppler drop in pitch of HAL's voice that made my hair stand on end...few death scenes in movies made such an impression.

What creeped me out the most in the movie is the "Ahaaaa ahaaaa ahaaaa" music when you first see the monolith in the pit on the moon. It sent shivers up my spine. For some reason though they didn't do the music just right in that part for the DVD version so it just doesn't make me feel nervous like the tape version's music did. Maybe they will go back and fix it one day.