r_rolo1
King of myself
...unless, like Willem hinted, if thay have the same base chemistry (DNA, proteins, sugars..... ) and the same way of coding DNA. That in fact would be a strong evidence of panspermia.
What if Alpha Centauri has no planets?
- Thread starter Magma_Dragoon
- Start date
Wodan
Deity
Gotta love those progenitor aliens.
Why don't we have a BEM smiley? Well,
has got to suffice. 
Even that is highly unlikely. Our base DNA was created by a long process of evolution, from the first single celled organisms through the whole reptilian/dinosaur period which stretched millions of years. Then finally to the mammalian code which we've come from. Any microorganism that migrated to another planet in the universe would be so primitive that even if it managed to adapt itself to an alien environment, the long term evolution into even a single celled organism would be quite different than our own current genetic makeup. We still carry within us DNA coding that we inherited from some creature that lived on this planet millions of years ago. It's next to impossible that the same genetic structure would manifest itself in some other environment, and then follow in a way similar enough to directly adapt to ours.
The chances are that if panspermia did occur it was only through the migration of base amino acids, which has been shown to be possible. Any higher form of organic structure probably wouldn't survive the cosmic radiation it would encounter. So once those basic elements arrived on another planet it would have to start from scratch, the same way it did here. With the result that any higher life forms that evolved would no doubt have a completely different DNA structure than ours.
That still doesn't justify the assumption that any alien life form we encounter will necessarily be dangerous to us. What makes you think the local diseases will even be compatible with our biology? We have no alien bacteria to base it on!
And there's nothing saying we absolutely have to colonise every planet that can support carbon-based life. If we find a planet full of bacteria, so what?
frekk
Scourge of St. Lawrence
Or that old TV show from the same time period ... I used to watch this as a kid:
http://en.wikipedia.org/wiki/The_Starlost
Yeah, I remember that one. A bit cheesy but I kind of liked it. I never realized they had a couple of sci-fi big-wigs on the crew. Between Harlan and Ben, it should have done well. Too bad the corporate types had to stick their noses into it.
frekk
Scourge of St. Lawrence
Me neither, I just found out two minutes ago.
It was a brilliant concept, especially for a television series ... the problem was in the execution of it. The idea should probably be revisited someday by someone who knows how to produce television sci-fi. Ron Moore, somebody like that.
Magma_Dragoon
Reploid
- Joined
- May 10, 2008
- Messages
- 2,354
Lets hope we run into the Protoss before we meet the Zerg. HAIL TASSADAR!
frekk
Scourge of St. Lawrence
It's probably actually better if they don't get the rights to it and don't have anything to do with the original franchise in any way, shape, or form. It has a bad reputation as one of the worst sci-fi series ever made. They should just take the essential idea and make something new.
AutomatedTeller
Frequent poster
I have no doubt that humans will colonize other planets - it just makes sense as a survival mechanism for the species.
I am pretty sure there is some form of intelligent, alien life out there, though I have no idea if we'll encounter it or when. Space is big...
I am pretty sure there is some form of intelligent, alien life out there, though I have no idea if we'll encounter it or when. Space is big...
Arexack_heretic
Emperor
What Willem said.
Yeah he is right, even IF panspermia is taken as a given and DNA the general templete for inheritance, there is no guarantee that anything like earth carbon-nitrogen-oxygen based life will arise.
Even on earth several archeabacteria have a divergent code, many have several divergent nucleic acids and some even use several different aminoacids to build their proteins.
Basically the further back you go evolutionwise, the greater the postential for divergence. Each minor step in evolution is built upon an earlier form and thus is basically limited to choices previously made.
Although much code is just edited in 'do not read' tags in modern species to speak in coders terms, allowing much permutation, microorganisms are highly optimized critters and as such do not have a long retention of stuff not neccesary for survival. Allowing much less back-tracking once a choice is taken. Basic choises as what type of biochemistry are only available at the most basic level of evolution. (thankfully Mo's are so small and mindboggling prollific that pockets of old populations usually survive way past their 'expiration date')
So given that the local environment would be most crucial in these choises, only the most basic of organisms would be viable as a panspermia agent.
Maybe even as basic as only a set of biomechanical replication strategies
of which DNA/RNA are two of the same type, the latter being less phosphorous dependent IIRC, but also less stable in our prevalent environment.
(In high degree due to destructive enzymes created in defence by DNA-lifeforms against RNA-highjackings such as retrovirusses.)
(Hmm DNA is like a higher level code used for interaction and easilly edited and repaired, while RNA is like machine code used for internal purposes. A computer can be hacked easilly with machine code messages, if access is acquired, same with cells. RNA virusses that manage to survive RNAses are transcribed into DNA and then safe -largely- to run their malicious code to the incidental ruin of the cell.)
erm...sorry 'bout the ranting...it is a field that excites me.
edit: oh on topic: No matter if no planets are at AC, we'll just pick another location, maybe a proven likely location or just some other unexplored region and exclaim "here be dragons" erm "aliens" or "terrestrial, earthlike planets" or whatever. Just like with martians, SciFi has a tendency to become outdated when now achieves or overreaches the extrapolated. Some SF is just baseless speculation or fantasy in a futuristic setting, but much is really been thought out really well, still the nature of SciFi is extrapolation and anyone versed in the nature of statistics or basic mathematical modelling can tell you extrapolation is dangerously unreliable.
It's guesswork, sometimes educated, sometimes based on unfounded but fun assumptions... such as intelligent life on mars.
Even when defuncted by later developments, it makes for exciting "what if" scenarios that could still be viable.
I saw a bit of "escape from NewYork" yesterday which has the opening line of "It is 1994...NOW" heh, now that is just writing with a expiration date, but it's another way of expiring SF. One way of dealing with this as reader/viewer is to access it as historical or fantasy setting instead. Ranting again. Must be in semantic mode.
Yeah he is right, even IF panspermia is taken as a given and DNA the general templete for inheritance, there is no guarantee that anything like earth carbon-nitrogen-oxygen based life will arise.
Even on earth several archeabacteria have a divergent code, many have several divergent nucleic acids and some even use several different aminoacids to build their proteins.
Basically the further back you go evolutionwise, the greater the postential for divergence. Each minor step in evolution is built upon an earlier form and thus is basically limited to choices previously made.
Although much code is just edited in 'do not read' tags in modern species to speak in coders terms, allowing much permutation, microorganisms are highly optimized critters and as such do not have a long retention of stuff not neccesary for survival. Allowing much less back-tracking once a choice is taken. Basic choises as what type of biochemistry are only available at the most basic level of evolution. (thankfully Mo's are so small and mindboggling prollific that pockets of old populations usually survive way past their 'expiration date')
So given that the local environment would be most crucial in these choises, only the most basic of organisms would be viable as a panspermia agent.
Maybe even as basic as only a set of biomechanical replication strategies
of which DNA/RNA are two of the same type, the latter being less phosphorous dependent IIRC, but also less stable in our prevalent environment.
(In high degree due to destructive enzymes created in defence by DNA-lifeforms against RNA-highjackings such as retrovirusses.)
(Hmm DNA is like a higher level code used for interaction and easilly edited and repaired, while RNA is like machine code used for internal purposes. A computer can be hacked easilly with machine code messages, if access is acquired, same with cells. RNA virusses that manage to survive RNAses are transcribed into DNA and then safe -largely- to run their malicious code to the incidental ruin of the cell.)
erm...sorry 'bout the ranting...it is a field that excites me.
edit: oh on topic: No matter if no planets are at AC, we'll just pick another location, maybe a proven likely location or just some other unexplored region and exclaim "here be dragons" erm "aliens" or "terrestrial, earthlike planets" or whatever. Just like with martians, SciFi has a tendency to become outdated when now achieves or overreaches the extrapolated. Some SF is just baseless speculation or fantasy in a futuristic setting, but much is really been thought out really well, still the nature of SciFi is extrapolation and anyone versed in the nature of statistics or basic mathematical modelling can tell you extrapolation is dangerously unreliable.
It's guesswork, sometimes educated, sometimes based on unfounded but fun assumptions... such as intelligent life on mars.
Even when defuncted by later developments, it makes for exciting "what if" scenarios that could still be viable.
I saw a bit of "escape from NewYork" yesterday which has the opening line of "It is 1994...NOW" heh, now that is just writing with a expiration date, but it's another way of expiring SF. One way of dealing with this as reader/viewer is to access it as historical or fantasy setting instead. Ranting again. Must be in semantic mode.
r_rolo1
King of myself
RNA is less stable than DNA because it can't form a stable double helix as easily ( due to the fact that 2'-OH of RNA ribose destabilizes a possible double helix structure based on RNA )... Since it can't form a double helix so easily, it becomes more reactive in Hidrofilic enviroments than DNA ( the bases are exposed to the watery medium ) , thus shortening his life as a organized structure.
OTOH RNA is much more plastic than DNA and in some configuations it even has catalitical properties....
This makes lots of people to think that life on Earth may have passed by a stage that both cataysis and information storage functions were made by RNA strings, with both DNA and proteins coming later
/biochemistry lesson
About panspemia: if we discovered a life form of other planet that was carbon based, I would not be surprised; if it had aminoacids, DNA or DNA like molecules ( with other basis isntead of ATGC ) ,lipids and sugars, I would be a little suspicious ( but given Miller's experience, it would not be surprising at all to find carbon based life forms using that kind of coumpounds ); if it has L-aminoacids , D -sugars , triglicerids, ATGC based DNA,etc .. , i would be highly suspicious of panspermia; if it had the same DNA-aminoacid coding than a Earthlife form and virtually the same proteins , I would be pretty sure that panspermia had happened somehow.
And linking to MagnaDragon concerns: only in the last two stages a alien life form could be physically dangerous to us and a virus would most likely need the last stage. So, if we got a alien cold ( or the aliens get a Earth flu ), I would bet my money that panspermia had happened ( and that we could use our current biochemical knowledge + some investigation of the native enviroment to get some kind of cure/vacine/paliative )
OTOH RNA is much more plastic than DNA and in some configuations it even has catalitical properties....
This makes lots of people to think that life on Earth may have passed by a stage that both cataysis and information storage functions were made by RNA strings, with both DNA and proteins coming later
/biochemistry lesson
About panspemia: if we discovered a life form of other planet that was carbon based, I would not be surprised; if it had aminoacids, DNA or DNA like molecules ( with other basis isntead of ATGC ) ,lipids and sugars, I would be a little suspicious ( but given Miller's experience, it would not be surprising at all to find carbon based life forms using that kind of coumpounds ); if it has L-aminoacids , D -sugars , triglicerids, ATGC based DNA,etc .. , i would be highly suspicious of panspermia; if it had the same DNA-aminoacid coding than a Earthlife form and virtually the same proteins , I would be pretty sure that panspermia had happened somehow.
And linking to MagnaDragon concerns: only in the last two stages a alien life form could be physically dangerous to us and a virus would most likely need the last stage. So, if we got a alien cold ( or the aliens get a Earth flu
), I would bet my money that panspermia had happened ( and that we could use our current biochemical knowledge + some investigation of the native enviroment to get some kind of cure/vacine/paliative )Eclipse-X010
Imperial Ascended Being
This is assuming the alien species was either non-sentient or some what passive: i.e. not interested in annexing Earth. After all: If a virus were to infect the human race it is most likely that sucha species would rather watch us die then help us. Then they would have a planet complete with cities, agriculture and ecosystems and probably enough knowledge to find the cure for any diseases that arise when they begin to populate it.
Arexack_heretic
Emperor
indeed! In fact even the basic mechanism for gene-translation from DNA to protein is mediated by an RNA complex.
The Earthlife-choices for the handedness of steriometric(?) molecules would be a good marker to test panspermia on as it is one independent of survival odds.
If I'm right, for an biochemistry it does not matter much which to be able to assimilate, most likely at the most early start mirror-biochemestries may develop...untill such time that one or the other manages to convert the opposite metabolites or create more of it's own type. (in a zero-sum survival environment). In fact this point would probably be the first time one can speak of a lifeform.
Assuming panspermia, this stage is skipped and a biochemistry is in place and thus identical. Assuming independent origination, the handedness of these molecules in an otherwise similar biochemistry should be roughly evenly devided (50% deviation).
The latter would require assuming that our biochemistry is inevitable, which is very highly unlikely as well.
But as our number of examples of functional biochemistries in earthlike is severely limited, making any such assumptions is as rash as estimating the likelyhood of life anywhere.
(e.g. our dataset is too limited! it needs further study.)
The Earthlife-choices for the handedness of steriometric(?) molecules would be a good marker to test panspermia on as it is one independent of survival odds.
If I'm right, for an biochemistry it does not matter much which to be able to assimilate, most likely at the most early start mirror-biochemestries may develop...untill such time that one or the other manages to convert the opposite metabolites or create more of it's own type. (in a zero-sum survival environment). In fact this point would probably be the first time one can speak of a lifeform.
Assuming panspermia, this stage is skipped and a biochemistry is in place and thus identical. Assuming independent origination, the handedness of these molecules in an otherwise similar biochemistry should be roughly evenly devided (50% deviation).
The latter would require assuming that our biochemistry is inevitable, which is very highly unlikely as well.
But as our number of examples of functional biochemistries in earthlike is severely limited, making any such assumptions is as rash as estimating the likelyhood of life anywhere.
(e.g. our dataset is too limited! it needs further study.)
r_rolo1
King of myself
They would have all the interest in the world ( pun intended ) in helping us, even for their own safeguard: only the heavens know what a alien bug genetic code, combined with some of the Earth genetical viral code that all the Euchariots bring buried in their genome can give ( not counting with the possibility of the alien bug infected a cell at the same time than a Earth bug and they trade genetical intel ... it is not that common per se, but it is most likely the genesis of most of the flus: pig virus meets new and improved chicken virus... ) and it could backfire on them....
Of course if the consider themselfs far superior to us, they can simply cauterize the planet to stop it
... just like we do to chickens and pigs
Arexack_heretic
Emperor
We must do it in the most humane way possible...
I suggest rape and pillaging followed by nuclear death.
Or would that aliens do it in the most alien way imaginable...uhh..
injecting us with their sick hybrid children?
Seriously the most logical course in any case would be an enforced quarantine.
No scarcity of planets (that we know of) when you can go anywhere on a whim.
Maybe get humans to self-sabotage any expansion into space (not much incentive needed, just show some shiny baubles).
This does require keeping something here enforcing the Q, maybe sterilisation is more efficient in the long run.
But if visitors have our current level of technology, they have been underway a lo-ong time and might not considder leaving an option...or might just never want to set traction-appendage on solid ground ever again and not bother with us at all.
I suggest rape and pillaging followed by nuclear death.
Or would that aliens do it in the most alien way imaginable...uhh..
injecting us with their sick hybrid children?
Seriously the most logical course in any case would be an enforced quarantine.
No scarcity of planets (that we know of) when you can go anywhere on a whim.
Maybe get humans to self-sabotage any expansion into space (not much incentive needed, just show some shiny baubles).
This does require keeping something here enforcing the Q, maybe sterilisation is more efficient in the long run.
But if visitors have our current level of technology, they have been underway a lo-ong time and might not considder leaving an option...or might just never want to set traction-appendage on solid ground ever again and not bother with us at all.
Arexack_heretic
Emperor
Double Post. sorry
Some highly intelligent people here, rarely as a mechanical engineer do I feel outclassed but I have no idea what some of you are talking about. You guys figure out the biology I'll just buld the damn space station. 
Anyhow, how do you guys feel about aliens visiting us for pretty much as long as human civilization has been around? There are countless records of UFOs from Heiroglyphics to Columbus to military documents. Being far superior, say having a million years more developed knowledge of physics, there really would be no interest to them making any kind of large scale contact with us because we would have nothing to offer them.
Looking down on our planet as whole you would see bombs going off daily, RPGs launched across borders, and military occupations. They most likely view us as very primitive destructive animals, which is why if they are visiting us they simply pluck people up, do some experiments (the same way we endlessly perform experiments on monkeys), and then plop us down or kill us.
Personally I believe that there are most likely aliens watching us (and who knows maybe they even seaded our planet) and they probably have underwater bases, and generally get from point a to point b on our planet underwater. It's fairly obvious that we know far more about space than we do about our own oceans and there accompanying underwater networks of caves.
Well now I sound crazy, cheers
Anyhow, how do you guys feel about aliens visiting us for pretty much as long as human civilization has been around? There are countless records of UFOs from Heiroglyphics to Columbus to military documents. Being far superior, say having a million years more developed knowledge of physics, there really would be no interest to them making any kind of large scale contact with us because we would have nothing to offer them.
Looking down on our planet as whole you would see bombs going off daily, RPGs launched across borders, and military occupations. They most likely view us as very primitive destructive animals, which is why if they are visiting us they simply pluck people up, do some experiments (the same way we endlessly perform experiments on monkeys), and then plop us down or kill us.
Personally I believe that there are most likely aliens watching us (and who knows maybe they even seaded our planet) and they probably have underwater bases, and generally get from point a to point b on our planet underwater. It's fairly obvious that we know far more about space than we do about our own oceans and there accompanying underwater networks of caves.
Well now I sound crazy, cheers
Some highly intelligent people here, rarely as a mechanical engineer do I feel outclassed but I have no idea what some of you are talking about. You guys figure out the biology I'll just buld the damn space station.
How do you think I feel? At least you get to build the space station, I just get to lock up whatever punk decides to graffitti it.
