Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: ukmicky on 29/09/2005 03:29:38

Title: Could there be life on other planets?
Post by: ukmicky on 29/09/2005 03:29:38
Could there be life on other planets.

If you go by earths example then shouldnt the anwser be,unlikely.

The earth has been around for about 5 billion years, and yet life has only started here once, as all life on earth is related.

once in 5 billion years would mean life must be so hard to start in the first instance that maybe life on earth is just a fluke[:)]

There are also many other factors that have got be taken into account which has aided life and complex life on our planet to survive.

Like our position in our galaxy,our type and size of our sun and the fact that its not a binary. Jupiter handy for removing the odd comet that comes our way. the moon. the tilt of our planet very handy that. the size of our planet and its position in our solar system ,it's molten core , magnetisphere. oxygen nitrogen mix. the list could go on for ever.

May be our planet is unique and the life on it is unique. is it so unlikley that we are alone,could we be the first.[:)]

Michael                                      (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa186%2Fukmicky%2Frofl.gif&hash=481319b762ee9d57cda15e90d2e83ee6)
Title: Re: Could there be life on other planets?
Post by: neilep on 29/09/2005 13:38:16
I have no doubt whatsoever that there IS life elsewhere.

Yes, the circumstances required for life are not condusive to a mass outbreak where ever we look in the Cosmos but when you consider that our Sun is one of three-five hundred billion suns in our galaxy, and our galaxy is one of three-five hundred billion galaxys (give or take a few billion !)...and it has been shown that there are indeed many many many planets out there, far more than we ever could imagine.....the chances that this planet is the only planet that supports life is not even worth considering.

And life can take many types and forms. Just dive in the ocean and keep going down and you'll find life that doesn't require light and oxygen to exist, check out the deepest dankest caves and pools, play around in the hottest springs and you'll find algae and stuff, just check the back of your fridge, I'm sure there is life there that is developing it's own intelligence !!!

Life as we know it is only contained to our planet, life is out there , it has to be, the friggin Universe is just too friggin large and the maths make it so !!..and who knows what other ' types' of life exist !


It is even suggested that life on this planet hitched a lift in/on a meteor that crashed landed here.



STAR TREK QUIZ:

I have used two well know Star Trek Phrases above, what are they ?

Prizes will be determined by the gender of the quiz winner !


Men are the same as women.... just inside out !! (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fwww.zerogain.com%2Fforum%2Fimages%2Fsmilies%2Faction-smiley-075.gif&hash=84631c0c4a382b5e68463904b7b9fddf)
Title: Re: Could there be life on other planets?
Post by: johndiver on 29/09/2005 15:31:26
UK: Your concern is real but your logic is flawed.
Life is simply the result of complex chemistry. Molecules such as DNA control chemical reactions which consume surrounding molecules and use their pieces to make copies of itself. Whenever we have a liquid solvent (water, ammonia, methane), carbon-based molecules, and a substrate (silicon-based clay) there exists a possibility that one or more molecules will form that have the properties of encoding information, cutting apart other molecules, attaching smaller molecules into strings of carbon, utilizing energy from sunlight or chemical reaction, and repairing the information carrying molecule. Once this system forms and is able to withstand environmental stresses, then the base of life has begun. Whether it evolves into sapient beings or beautiful flowers is another matter.
The other big theory out there (pun intended) is Panspermia. Astronomers have discovered organic molecules floating in interstellar space and have raised the possibility that comets have picked up these molecules and crashed into earth and other planets with these precursors of life. If so, then comets may be spreading the seeds of life around the galaxy, where they can replicate and evolve as conditions permit.
If you'd like to learn more, I strongly suggest reading the Gaia hypothesis by James Lovelock. Also use the search terms "carbon chauvinism" if you'd like a real interesting look at how carbon became the molecule of life.
Title: Re: Could there be life on other planets?
Post by: ukmicky on 30/09/2005 00:26:41
Thank you all for your comments.

It is a horrible thought that we could be alone; I personally prefer to believe that the universe is teeming with life.
However I’m one of these people that has to always question everything in order to learn and then believe what’s generally accepted. Is it a good or bad thing, I don’t know really, but I do know it tends to piss off many people.[:)]
                      --------------------------------------------------------------------------


The building blocks for life may have come here from space or they could have been created on the earth through electrical storms
However it is still a fact that every living thing on earth is related, we all come from one single common ancestor. Whether you’re talking about plant life or animal.We share sixty percent of our DNA with the humble banana [Neil your related to a banana][:D] or the tree that produced it.[:D]
And unless the double helix and a large percentage of its DNA structure is a universal blue print for life, it must mean all life on earth emerged after one single event that created one single simple life form that somehow survived to divide and evolve into all the various living forms of life, be it animal or plant.


Which means the start of life on earth happened once, one event in the total history of the world. That’s says to me that the chances of it happening lots of time’s on lots of extraterrestrial planets that are like or unlike ours is remote.

Maybe it has happened again in a distant galaxy far far away but it must be such a rare event that it also says to me that ok we may not be alone in our universe but as far as the Milky Way is concerned we could be..

If life here on earth was created on more than one occasion then the chances are that there would be other life forms of life that didn’t share any DNA characteristics with us, possibly with other forms of DNA structures, maybe even triple helixes,
or maybe something other than DNA
Michael                                      (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa186%2Fukmicky%2Frofl.gif&hash=481319b762ee9d57cda15e90d2e83ee6)
Title: Re: Could there be life on other planets?
Post by: johndiver on 30/09/2005 03:20:00
I have read a few essays about how finely-tuned the world is for life to exist ... for example, Gravity is roughly 10^39 times weaker than electromagnetism. If gravity had been 10^33 times weaker than electromagnetism, stars would be a billion times less massive and would burn a million times faster, and no astronomers would ever come into existence to talk about this matter.
This is the sort of theorizing that makes us think about what life is from the view of quantum physics.
http://en.wikipedia.org/wiki/Carbon_chauvinism
http://en.wikipedia.org/wiki/Anthropic_principle
Title: Re: Could there be life on other planets?
Post by: ukmicky on 01/10/2005 02:56:37
Once life has been created then it seems going by earth’s example, life will evolve and find a way to survive even in the most extreme of environments.

However Its not really about how finely tuned the earth is for life to survive, as life will try to make do with whatever its got and will explore the potential of any environment it happens to be presented with.

The problem is life has got to be created first and that it seems is not as easy as people seem to believe.

Meteorites have been found to contain amino acids the building blocks of life, one meteorite was found to contain over seventy different types but only six of the types that are essential for life.

Dumping all the required ingredients, the twenty or so amino acids etc required for life in a test tube is one thing,
but it happening naturally is another.

Remember, a far as we know it has only occurred on earth once
G
etting all the required ingredients together at the right time with the right conditions maybe not that easy for nature to achieve  
[:)]

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Title: Re: Could there be life on other planets?
Post by: johndiver on 02/10/2005 23:47:45
Keep in mind that our planet could be considered toxic to other life forms. For example, we have free oxygen in the air and dangerous amounts of calcium in the our oceans. Not to forget, do you realize that water is able to dissolve more substances than any acid?
Either way, I like James Lovelock's observation that in order to determine the likelihood of life on another planet, simply look for the presence of atmospheric molecules that are unstable and therefore likely produced by a lifeform. That way, he argued, to look for extraterrestrial life you'd be better off investing in better telescopes than in rockets to reach Mars with sensing devices.
Title: Re: Could there be life on other planets?
Post by: another_someone on 11/10/2005 22:49:00
quote:
Originally posted by ukmicky

Could there be life on other planets.

If you go by earths example then shouldnt the anwser be,unlikely.

The earth has been around for about 5 billion years, and yet life has only started here once, as all life on earth is related.

once in 5 billion years would mean life must be so hard to start in the first instance that maybe life on earth is just a fluke[:)]

There are also many other factors that have got be taken into account which has aided life and complex life on our planet to survive.

Like our position in our galaxy,our type and size of our sun and the fact that its not a binary. Jupiter handy for removing the odd comet that comes our way. the moon. the tilt of our planet very handy that. the size of our planet and its position in our solar system ,it's molten core , magnetisphere. oxygen nitrogen mix. the list could go on for ever.

May be our planet is unique and the life on it is unique. is it so unlikley that we are alone,could we be the first.[:)]

Michael                                      (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa186%2Fukmicky%2Frofl.gif&hash=481319b762ee9d57cda15e90d2e83ee6)



Would somebody tell me what they mean by 'life'?  If we are to say whether life exists elsewhere, then we should first clearly define what it is that we would define as 'life'?

If all you are looking for is reproduction, then stars themselves will, in their death throws, beget a new generation of stars.  There now appears a significant possibility that some sort of bacterial life exists on Mars.  What kind of life are you looking for when you ask about extraterrestrial life?

Beyond the question of whether there is life out there, is the question of whether life is capable to crossing the vast expanse of nothing to reach us, or that we might reach them.  If the closest planet that supports life were to be several hundred million light years away, then even if they could send out a ship to reach us, by the time that ship returned home, several hundred million years would have elapsed on their own planet, and the original purpose of their mission would seem rather irrelevant to the world they would return to.
Title: Re: Could there be life on other planets?
Post by: Ultima on 12/10/2005 19:35:56
The problem here is that you are looking at SPECIALISED HIGHLY EVOLVED forms of life that have been home grown here on Earth and trying to put them into some sort of inter stella standing! Saying that life only appeared on Earth once and everything is related isn't entirely true...

How do you know there aren't new forms popping in to existence all the time but they don't have a chance because of everything else around them? It's a bit of a first come first served thing in evolution, then you have to wait for something to become extinct to take it's place.

I don't think I could easily compare an  archaebacteria extremophile living in an ocean thermal vent or deep within solid rock with a Kangaroo... they aren't even chemically that similar they use completely different processes to fuel them, and one saves people from wells, the other doesn't! People have just started to find these "giant viruses". It's not clear how many there are, how long they have been around or what there role is, or if they can be called "alive".

Looking at all those "what if this physical variable was changed life wouldnt exist" etc... How do you know??? Have you created some massive physical model and processed it for billions of billions of years to see what kind of structures emerge??? Life is just the self organising and replication of a stable pattern or structure of molecules, at least in my book! Or not even molecules... electrons in plasma's, bits of data, anything so long as it's a persistent self replicating pattern that is subject to some process of change through an environmental interaction.

http://en.wikipedia.org/wiki/Extremophile
http://en.wikipedia.org/wiki/Kangaroo
Title: Re: Could there be life on other planets?
Post by: ukmicky on 13/10/2005 03:59:51
originally posted by ultima The problem here is that you are looking at SPECIALISED HIGHLY EVOLVED forms of life that have been home grown here on Earth and trying to put them into some sort of inter stella standing! Saying that life only appeared on Earth once and everything is related isn't entirely true...

How do you know there aren't new forms popping in to existence all the time but they don't have a chance because of everything else around them? It's a bit of a first come first served thing in evolution, then you have to wait for something to become extinct to take it's place.

I don't think I could easily compare an archaebacteria extremophile living in an ocean thermal vent or deep within solid rock with a Kangaroo... they aren't even chemically that similar they use completely different processes to fuel them, and one saves people from wells, the other doesn't! People have just started to find these "giant viruses". It's not clear how many there are, how long they have been around or what there role is, or if they can be called "alive".

Looking at all those "what if this physical variable was changed life wouldnt exist" etc... How do you know??? Have you created some massive physical model and processed it for billions of billions of years to see what kind of structures emerge??? Life is just the self organising and replication of a stable pattern or structure of molecules, at least in my book! Or not even molecules... electrons in plasma's, bits of data, anything so long as it's a persistent self replicating pattern that is subject to some process of change through an environmental interaction
.
__________________________________________________________________________________________________________________


TO ULTIMA

Firstly let me appologise for the format of the following or any typing errors. i'm tired i need some sleep[|)]
________________________

I’m not just talking about complex life forms I’m talking about even the most basic forms of life on earth. The smallest and simplest forms of life the single celled organisms called prokaryotes which inhabit almost every place possible on earth from deep ocean vents or hot springs to the freezing poles share RNA/DNA with us.
So yes your kangaroo may not look similar to extremophiles halo bacteria living in deep ocean thermal vents but we do have a common ancestor  and in reality are related to you and me.And yes they may use different life processes but follow you family tree far enough back and you will find your ancestor which didn’t use oxygen but released it as a waste gas.  
Ok they didn’t walk around on arms and legs but we are genetically related to them.
And so as far as we know Yes every living thing on earth is related and my statement is entirely true.

It is a fact that everything, be it algae, bacteria, a plant or you and me share parts of our genetic makeup with each other, there are individual genes on the ribosomal RNA which are common to all life plant or animal and the only way that is possible, the only way is if we all share a common ancestor.

Also every living thing on earth needs the same 20 amino acids.
Every living thing has cell structures (Human cells evolved from plant cells).
We all use the same nucleotides in our genes.
We all use Adenosine triphosphate (ATP) to transfer and store energy within our cell. ATP is also used for the synthesis of nucleic acids. The most common nucleic acids are deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Nucleic acids are found in all living cells and viruses.
(Even though part of our genetic makup most likely came from virus's that integrated into there hosts DNA,viruses do not come under most people’s definition of life)  
ATP molecules are also used to store the usable energy that plants convert in cellular respiration. There are so many things which are common to all life on earth that the one and only explanation is we come from one single event which created one single life form on earth.

We only have proof that life has started  on earth once and going by that evidence means life is such a hard process to begin naturally, we could be on the only planet in our galaxy with life. its possible.
And as the rest of the universe is basically made of the same stuff as us and our planet and many of the rocks and comets floating around in space contain amino acids which are the same as whats found on earth (no new ones), it’s a good bet that any life on any other planet would share similarities and with us like be carbon based and be dependent on water.
and so any difficulties the earth has had in respect to the creation of life,any other planet would probably have the same .[:)]

I would love to be wrong, but i bet life isn't common in the universe and i bet it's never found on mars or anywhere else in our solar system.

Most people hate the thought that we could be alone or that life is very rare event in the universe,and unfortuanatly that possibility does exist.
Michael                                      (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa186%2Fukmicky%2Frofl.gif&hash=481319b762ee9d57cda15e90d2e83ee6)
Title: Re: Could there be life on other planets?
Post by: Ultima on 13/10/2005 09:59:32
There are 22 genetically coded for amino acids; some dude added in two extra codons for unnatural amino acids to a bacteria to produce new proteins! Plus some of these other amino acids were found very recently and weren't known to exist. So it's quite possible there is some life hanging around using some amino acid no one noticed before. I remember reading someone had found a bit of life using a random amino acid, different to everything else... I'll see if I can dig up a reference.
Because all life is made up of the same types of molecules doesn't make them the same or related. It's just means it's the most stable and efficient form to be in on the Earth.
You will have to define what you mean by "Life started once" as soon as we had biological molecules surrounded by membranes (or proteins) reproducing we had life. I imagine new forms start from the ground up more often than not, but they get consumed by something more advanced and bigger around them.
We also know that throughout history completely unique sets of organisms nothing like what we see today got killed off in the "Permian-Triassic extinction event" which wiped out about 90% of all species of life. Everything thats here today is from 10% of the types of life that used to exist. If you go further back there are more extinction events, who knows what sort of zany life existed before life formed shells to leave fossil records!
I understand what you are trying to get at, but reasoning that chemically life is similar means they must be related, does not hold up in the real world.
Life picks out the best way to do things as shown through convergent evolution of radically different species into the same niche role. It only makes sense that the same system of chemically stored information is used. I'm no chemist, but I don't think there are that many other molecules you could use to do the same job. Silicon can replace Carbon but you don't get anywhere near the same amount of molecules to use. RNA and DNA are good examples that there is more than one way to do things. One of which is more complicated and newer than the other!
It's like saying that all electronic devices are exactly the same because they use electrons, but in reality there have been several seperate reincarnations of electronics in different froms doing the same thing.

Chemistry is just the hardware, LIFE is the software that persists within the chemical framework! [:D] You can tell im a Computer Scientist/A.I. peep looking at Biology!
Title: Re: Could there be life on other planets?
Post by: Dr. Praetoria on 13/10/2005 21:57:11
One interesting discussion I heard, was that such a life creating planet would have to have a moon that would stabilize it, permitting seasons or climates that allowed such life to form.
Doc
Title: Re: Could there be life on other planets?
Post by: another_someone on 14/10/2005 03:17:02
The moon supposedly stabilises the Earth's orbit, but it also creates tides.  I do believe that there has been speculation that life started in the intertidal regions.  If this is the case, then the moon would have been required to create the tides.

Another factor where the moon may have been important may have been in the nature of its formation.  The current theories seem to indicate that the moon was created by a collision between the Earth and another body, and that this other body skimmed a fair amount of material from the surface of the Earth, but did not take material from the depths of the Earth (hence why the moon is poor in iron, and other heavy elements that form the mantle and core of the Earth).  This would indicate to me that the collision may have left the Earth with an extra thin crust, which might than have been more conducive both the volcanism (including deep sea vents), and to plate tectonics.  Another theory about the origin of life was that it originated near deep sea vents, where the energy of the vents was used to fuel early life (what does seem certain is that the earliest life was not dependent on the kind of photosynthesis that is so common today, and so would have required some other energy source).

I don't personally believe that stability is that important for the creation of life.  On the contrary, I believe life is a consequence of instability.

Certainly, the more variability there is in the environment, the more opportunity there will be for evolutionary change.  In that respect, the creation of tides is one form of local environmental variability, although the Earth has has much more significant environmental shifts over its history, and through them, it has been driven to ever more radical evolutionary changes in the life it supports, as that life must constantly adapt to the shifting environment.  The regular mass extinction events that occurred on this planet, although they were clearly toxic to the life of the time, were each a prerequisite for the next stage of evolutionary progress.

As I mentioned earlier, there is still the question of what is life?

Ukmicky has suggested that DNA/RNA is a common factor for life on earth.  I think Ultima has better identified that what is import is the patterns, the information, that is stored within DNA, rather than the DNA itself.  Probably, even more relevant than the information stored in the DNA itself, is the nature of the system that this information describes.  What we see as living organisms are enclosed bodies (cells) that contain a complex set of micro environments that operate to isolate a complex series of interconnected chemical processes.  The DNA stores the blueprint for the protected system of chemical reaction vessels that is a living cell, and it ensures that each system is an approximate replicate of its parent, but, in my view, it is the system that is important, not the blueprint.

johndiver has mentioned that the environment on this planet might be toxic to many life forms.  In my view, that actually is an important reason why life may indeed have developed on this planet.  As I said above, living cells are a system of isolated reaction vessels, and one reason that they do need to be isolated from the outside environment is precisely because the outside environment would be toxic to the internal contents of the cell.

The amino acids that seem to be so easily available in much of the universe may be a basic building block for life on this planet (and maybe on other planets), but having the building blocks is not of itself enough to construct life - there must have been environmental factors that caused those building blocks to come together in the way they did.

The other factor that no-one has mentioned is that while so much has been said about amino acids, that are used to build proteins, enzymes, and DNA; what about the lipids and sugars that are also important constituents or life?  Could early life have been formed without these?  If so, then what substitutes did early life use in their place?


http://www.cmbl.org.pl/vol9sup2/V9Suppl2Page97.pdf
quote:

The first forms of cellular life required membranes that were probably made of amphiphilic compounds such as lipids and phospholipids. Lipid membranes are crucial to the structure and function of all cells and their role in the origin and evolution of life is of considerable interest.

Title: Re: Could there be life on other planets?
Post by: ukmicky on 14/10/2005 04:30:38
To another_someone

when i wrote about dna/ rna i didnt quite explain it correctly
what i mean't was that we share them instruction within the dna that you wrote about. just like we share 98.4 % of our genetic material with chimpanzees and 60% of them instructions with a bannana,(thats the weird one) we also share identical instructions with every form of life on earth, plant or amimal. and the only way we can share identical material, complex identical instructions  with every thing is if everything is related. there is nothing on earth that is not related its a proven fact.
Not one of my facts but a proven scientific fact.

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Title: Re: Could there be life on other planets?
Post by: another_someone on 14/10/2005 05:12:42
To ukmicky:

OK, I probably was not addressing the totality of what you wrote either.

Ofcourse you are right, the fact (although I'm not sure that there is such a thing as a scientific fact, only scientific observations and scientific theories - but that is semantics) that we share so much of our DNA does mean that we must be related, but it does not show whether we are related by a single common ancestor, or by marriage.

There are many ways in which organisms exchange DNA, and the simpler the organism, the easier it appears to be to exchange DNA.  Bacteria exchange plasmids, and even higher organisms (as you pointed out) will capture viruses that will be integrated into their own DNA.  Thus, it is quite possible that several ancestors exist, and that DNA from some branches of of the tree of life (possibly now extinct) were integrated into other branches of the tree of life, and continued to survive as hybrids, these hybrids then out-competing the earlier thoroughbreds.
Title: Re: Could there be life on other planets?
Post by: Ultima on 15/10/2005 00:20:58
ukmicky I agree that today most multi celled life has it's roots with many common ancestors. But I disagree that this means "life started once".

As I mentioned we have mass extinction events all the time and life starts again. Most of the genetic material we share codes things which are common to all eukaryotic cells. I haven't checked but I doubt we share a great deal with prokaryotic life...

If every living thing was wiped out through radiation today; it would bounce back rapidly after the radiation subsided! Guess what it would look fairly similar to todays life because the same compounds are kicking around. Phospholipids form a membrane to encapsulate biological reactions, and you end up with some form of cell again. Because something is similar in appearance doesn't mean it's realted.
 
For years people thought flying foxes were bats, turns out when we looked in detail at their brains, genome and lifestyle they are closely related to lemurs and other primates (including us) and not bats. This kind of convergence is caused by a similar past and moving to the most efficient form to fit a niche environment. If that kind of thing happens on a large scale. It's not a great leap of the mind to imagine that chemically a similar process might take place. Granted this is pure speculation but it's near impossible to prove or disprove thanks to not being able to speed time up or accurately relate historical species 100% correctly.
Title: Re: Could there be life on other planets?
Post by: another_someone on 15/10/2005 03:37:55
To: Ultima,

The major hole that I can see in your argument is not that it is impossible, simply that within that part of history that we can see in the fossil records, that is not what happened.

We have had many mass extinction events, but at no time have we ever had all life wiped out, it has only ever been a case of wiping out most of the life on the planet.  What would happen if all life were wiped out is speculation.
Title: Re: Could there be life on other planets?
Post by: ukmicky on 15/10/2005 04:39:40
To another_someone

you got there before me with your above post. as for the other points raised i will post a reply.  but i need to check out something out first.




Michael                                      (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa186%2Fukmicky%2Frofl.gif&hash=481319b762ee9d57cda15e90d2e83ee6)
Title: Re: Could there be life on other planets?
Post by: Ultima on 15/10/2005 15:37:26
Yeah I did mention it was pure speculation [:D]
I think the main thing is you guys are thinking "whole new life" as in it's nothing like what is around now. I have very strong doubts that chemically anything else would arise on Earth for the pure fact that it's allready how it is. Unless some magical molecule from outer space plants some new form of life thats better suited than the current chemical systems it's just not going to happen. When I say life starts again, those 10% survivors are only going to be from a narrow band of specialisation and will evolve to form organisms that resemble closely what was there before. This includes resembling the same chemistry. If you are going to live in a harsh place on Earth certain things are going to be required.

The main thing that got me going is that Michael said we share 60% of our genes with a bananna. My questions is this. How many genes does a bananna have in it's genome compared with a human? It's like saying someone who has AIDS shares 100% of their genetics with HIV!!! It's ok to make the comparison with a chimpanzee because we are clearly related to them directly. We can see the history of common ancestors. You get all sorts of statistics saying how much we share with a fly or a cabbage etc. These are worthless; because we share the same codons for a protein that is vital for the survival of all eukaryotic cells doesn't mean we are related in anyway!

You get a lot of the chemistry of a cell for free such as the formation of a membrane, without any sort of genetics coming in to the picture. I can't believe that all known life would come from a single original self contained chemical reaction. I bet there were loads that worked in almost exactly the same way chemically with just a few differences between them. But regardless of how similar chemically they were they are unique and unrelated. The fact they all ended up forming something that looks remarkably similar is probably from crossover between them early in history and the addition of some form of genetics that allows them to converge on an efficient form that works. We still get this process happening now when single celled organisms divide and capture bits of the surrounding environment inside themselves or get infected by a virus and incorporate its genetics and proteins.
Michael you still haven't defined what you mean... In your eyes what would have to be visible to prove life started out from more than one source on the Earth? Some organism with radically different chemistry? Like say silicon instead of carbon based? What?
Title: Re: Could there be life on other planets?
Post by: Ultima on 15/10/2005 15:51:45
I have a question that might clear things up. I consider Viruses, Prions and Viroids in some form to be "alive" although they can't do everything themselves they are a persistent replicating form, they act on a different scale to cells persisting more through chemical reaction than active involvement with the environment around them.

Do you consider them a form of life?

If so thats instantly one form of life that is very different from a cell. A Prion isn't even genetic! It certainly wouldn't have evolved from a cell or vice-versa. I know any biologist wouldn't agree with me, but hey I can be as deluded as I like [:D]
Title: Re: Could there be life on other planets?
Post by: ukmicky on 15/10/2005 15:54:25
originally posted ultima
 The main thing that got me going is that Michael said we share 60% of our genes with a bananna. My questions is this. How many genes does a bananna have in it's genome compared with a human? It's like saying someone who has AIDS shares 100% of their genetics with HIV!!! It's ok to make the comparison with a chimpanzee because we are clearly related to them directly. We can see the history of common ancestors. You get all sorts of statistics saying how much we share with a fly or a cabbage etc. These are worthless; because we share the same codons for a protein that is vital for the survival of all eukaryotic cells doesn't mean we are related in anyway!

-------------------------------------------------------------------------
Yes it does


Michael                                      (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa186%2Fukmicky%2Frofl.gif&hash=481319b762ee9d57cda15e90d2e83ee6)
Title: Re: Could there be life on other planets?
Post by: Ultima on 15/10/2005 16:12:09
http://en.wikipedia.org/wiki/Nanoarchaeum
http://en.wikipedia.org/wiki/Mimivirus

Use the same organic chemistry but they just don't fit. They aren't even related genetically to anything. They share some genes with other organisms but nothing on the scale that directly relates them with anything!
So how do explain things like this keep being discovered?
Title: Re: Could there be life on other planets?
Post by: ukmicky on 15/10/2005 17:52:23
Their still studying the Mimi virus and yes they do believe it qualifies as life.
However it’s not quite that simple as they also believe the Mimi virus could be a cross between a form of bacteria and a virus rather than being a new branch of life.
The virus mimics bacteria hence its name Mimi and they believe it may be able to do so because it injected its genetic material into the nucleus of a bacteria allowing it to use the bacteria's ribosome RNA. Which is why it is able to create proteins and then replicate.
So rather than creating its own life force. It may have stolen it.
They need to study it further before they can be sure though, so at the moment they still don’t know what it is for sure..



Michael                                      (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa186%2Fukmicky%2Frofl.gif&hash=481319b762ee9d57cda15e90d2e83ee6)
Title: Re: Could there be life on other planets?
Post by: Ultima on 15/10/2005 19:49:29
A cross between a virus and a bacteria would seriously be a new form of life in my book. It's not like they are remotely similar or related in the first place! I agree that it's still early days...

Define what you mean by Life! damn it! [:D]
Title: Re: Could there be life on other planets?
Post by: another_someone on 16/10/2005 03:42:34
quote:
Originally posted by Ultima


Define what you mean by Life! damn it! [:D]



This was the question I asked a while ago.

The first distinction you have to make is between that which is living, and that which is a living organism.  My thumb is living, but few would regard it as an organism in its own right, because it cannot live except while attached to the rest of me.  On the other hand, one could argue that a virus (not including Mimi) cannot live except while attached to another organism.

Ofcourse, you could take this to its logical conclusion, and say that no animal is actually a fully self-sustaining living organism, since all animals depend upon obtaining nutrients from other living entities (e.g. humans need to eat vegetables in order to obtain vitamins that they themselves are not able to synthesise).

But, having made the point that we might regard a small part of a living organism as still being alive, and thus constituting 'life', the question arises as to how small a part of a organism may still be regarded as living?

It is commonly often considered that any part of the body that contains replicating cells may be regarded as living, but until recently it was regarded (and it is still open to debate how true this may or may not be) that mature nerve cells do not replicate - does this mean that the brain is not living tissue?

So, the question still remains, what criteria would you use to define life?
Title: Re: Could there be life on other planets?
Post by: another_someone on 16/10/2005 05:04:42
quote:
Originally posted by Ultima

I have a question that might clear things up. I consider Viruses, Prions and Viroids in some form to be "alive" although they can't do everything themselves they are a persistent replicating form, they act on a different scale to cells persisting more through chemical reaction than active involvement with the environment around them.

Do you consider them a form of life?

If so thats instantly one form of life that is very different from a cell. A Prion isn't even genetic! It certainly wouldn't have evolved from a cell or vice-versa. I know any biologist wouldn't agree with me, but hey I can be as deluded as I like [:D]



OK, so going back to the original question, whether there might be life on other planets?  If you were to travel to another planet, and find nothing but viruses (leaving mimi aside), and bearing in mind that viruses on their own are totally inert (i.e. they are not only incapable of reproduction, they are even incapable of any chemical synthesis), would you still say that you have found life on another planet?
Title: Re: Could there be life on other planets?
Post by: ukmicky on 16/10/2005 15:41:53
WHAT IS LIFE?

I suppose for something to be classed as life has to be able to feed to take in energy,and also has to be able to reproduce

Michael                                      (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa186%2Fukmicky%2Frofl.gif&hash=481319b762ee9d57cda15e90d2e83ee6)
Title: Re: Could there be life on other planets?
Post by: another_someone on 16/10/2005 17:56:27
quote:
Originally posted by ukmicky

WHAT IS LIFE?

I suppose for something to be classed as life has to be able to feed to take in energy,and also has to be able to reproduce

Michael                                      (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa186%2Fukmicky%2Frofl.gif&hash=481319b762ee9d57cda15e90d2e83ee6)


It is a partial answer.

The concept of feeding and taking in energy is very vague, and would be satisfied by most machines (a motor car would certainly satisfy that requirement - bearing in mind that the concept of feeding is not the same as finding your own food, because many things we consider to be alive do not find there own food, but are opportunistic feeders, waiting for food to come to them).  It must also be bourn in mind that many things we regard as living will only feed in the juvenile phase of their life, and live off their reserves when they are sexually mature.

If one were to consider viruses as living entities, since they are able to reproduce, but only with the assistance of another organism; then one could also regard the motor car as alive, insofar as it is capable of reproducing with the assistance of human beings, but not without that assistance.  This, I think, may be used as another argument for excluding viruses from the category of living things.  If we could create cars that would self-assemble, then the motor car would meet all of your requirements.

What is more interesting is the position of prions, since they do reproduce (given the right environment) without requiring the existence of any other living entity.  It may reasonably be argued that the environment that prions exist in must be created by a living entity, but there are many living organisms that can only live inside other living organisms.

As least as interesting is whether one would consider computer viruses or worms as living.  They have no chemical processes, but your definition of life said nothing about chemistry.  They do consume energy (albeit, not a great deal, but in the days before the Computer Misuse Act, one of the ways of convicting computer hackers was to charge them with theft of electricity), and they do reproduce themselves.

Another candidate for life is the stars themselves.  They are born by the collapse of the interstellar medium, which provides the food upon which they will live.  They then consume vast amounts of energy from the nuclear fusion that this food provides.  When they die, many of them will explode into a super-nova.  The shock waves from the super-nova will create the seeds for new stars to be born, and hence satisfy your requirement for reproduction.  If one accepts that stars themselves are alive, it may well be the simplest answer one could get to whether there is life elsewhere in the universe, albeit, it does not answer your narrower question, whether there is life on other planets.
Title: Re: Could there be life on other planets?
Post by: ukmicky on 16/10/2005 18:20:28
another_someone


yeah it was partial,i was in a rush had to go to pc world before it closed[:)]  

ok life as we know it can independently respond to its surroundings,grow and develop, reproduce,  take in energy. and is made up of one or more cells.
which basically rules out all of the above[:)]

Michael                                      (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa186%2Fukmicky%2Frofl.gif&hash=481319b762ee9d57cda15e90d2e83ee6)
Title: Re: Could there be life on other planets?
Post by: another_someone on 16/10/2005 20:13:16
quote:
Originally posted by ukmicky

another_someone


yeah it was partial,i was in a rush had to go to pc world before it closed[:)]  

ok life as we know it can independently respond to its surroundings,grow and develop, reproduce,  take in energy. and is made up of one or more cells.
which basically rules out all of the above[:)]

Michael                                      (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa186%2Fukmicky%2Frofl.gif&hash=481319b762ee9d57cda15e90d2e83ee6)



I think they key phrase here is 'life as we know it'.

I don't disagree with your other criteria, but I think I could easily apply those, as well as probably most other rational criteria you choose to use to define life, to a myriad of or entities that you would dismiss and not being living.

I think the problem with trying to define life (just as is the problem in trying to define 'intelligence' when one debates issues of 'artificial intelligence'), that the definitions people use are more about trying to prove our uniqueness than about creating a truly rational definition of these terms.

What you are asking is not really 'is there life on other planets', but 'are there things that look and behave like ourselves on other planets' - i.e. something that we can emotionally relate to as life.

http://mars.jpl.nasa.gov/life/index.html
quote:

Finding life isn't exactly easy--scientists aren't even satisfied yet that they have a definition for life that would work for any planet. It's a little easier to define what it means on Earth, but have we fully considered what alien life might be like? What if we were only looking for Earth-like life, and missed the other kinds of life that might be possible?



Personally, I'm not sure we even have an adequate definition of life on this planet.  As I said above, I suspect that our definitions are often more bound up in prejudice than in rational distinctions.  We are often too bound up in proving how special we are, rather than merely accepting that we are just a manifestation of ordinariness.
Title: Re: Could there be life on other planets?
Post by: neilep on 16/10/2005 20:24:05
While you debate about the definition of life, I still maintain that out there, amongst the cosmos is someone  probably unlike myself..and unlike yourself (or even very much like ourselves) who is also debating about life elsewhere in the cosmos.

Men are the same as women.... just inside out !! (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fwww.zerogain.com%2Fforum%2Fimages%2Fsmilies%2Faction-smiley-075.gif&hash=84631c0c4a382b5e68463904b7b9fddf)
Title: Re: Could there be life on other planets?
Post by: ukmicky on 16/10/2005 21:12:51
I did say in my first post "If you go by earths example"and yes i agree it may be wrong to consider life on earth as the only template but unfortuanatly thats the only evidence of life we have so far.

 


Michael                                      (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa186%2Fukmicky%2Frofl.gif&hash=481319b762ee9d57cda15e90d2e83ee6)
Title: Re: Could there be life on other planets?
Post by: another_someone on 16/10/2005 22:24:10
quote:
Originally posted by neilep

While you debate about the definition of life, I still maintain that out there, amongst the cosmos is someone  probably unlike myself..and unlike yourself (or even very much like ourselves) who is also debating about life elsewhere in the cosmos.

Men are the same as women.... just inside out !! (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fwww.zerogain.com%2Fforum%2Fimages%2Fsmilies%2Faction-smiley-075.gif&hash=84631c0c4a382b5e68463904b7b9fddf)



You are working on the premise that there are many possible opportunities for life to arise.  The question is, even if these opportunities exist, how many different ways are there to fulfil those opportunities?

If there are to be many solutions that are very similar to the solution we have on this planet, it implies that there are very few dissimilar solutions.

Ofcourse, depending upon how you define 'life', one may also ask whether every scenario that will satisfy the opportunity for 'life' would itself be something we would recognise as 'life'.

In order for life to be very similar to our own, it would have to develop on a planet on a planet very similar to Earth.

In the first instance, a planet rich in carbon, hydrogen, nitrogen, oxygen, and iron, is not at all unlikely, since many medium to large super-nova will create these elements.  Having significant supplies of uranium is slightly more unusual, and will only be created by larger super-nova.

The question about the significance of the moon, and the nature of its creation, has been raised.  What is the probability that a moon, created by the same mechanism as our moon, would have happened on one of these relatively rare planets (at about the right distance from the sun, and created from a large super-nova, and with the right sized sun).

Then, if you are looking for life that is sufficiently similar to us to actually be 'also debating about life elsewhere in the cosmos', then one has to ask, how many species on this planet are capable of such a debate?  If you come to the conclusion that only humans can, or could ever have, had such a debate (although one may consider whether dolphins, chimpanzees, or a like, may have such a discussion; but I think the answer is probably 'no'), then you must be looking to the creation of a species that is very rare indeed.  Even on this planet, one has to ask whether, if the death of the dinosaurs came a million years earlier, or a million years later, would humans even have developed on this planet?
Title: Re: Could there be life on other planets?
Post by: ukmicky on 21/02/2021 19:16:12
So I’m resurrecting a thread that I started 16 years ago ,how time flies.. So apart from this now being the longest running thread in naked scientists history  and maybe the world :) ,I have a question .


So we have just placed a new lander on Mars with with lots of new equipment in the search for the signs of life from when it had a thick atmosphere and surface water.

A NASA scientist on the telly said if the new rover discovers  that many moons ago (should be Phobos ago:)there was life on Mars that would then mean as both Mars and Earth  either has or had life it must mean that the universe must be teeming with it .

Isn’t that an absurd statement to make . Why would the discovery that there was once life on Mars mean the universe is teeming with life .
Title: Re: Could there be life on other planets?
Post by: evan_au on 21/02/2021 19:56:56
Quote from: OP
Isn’t that an absurd statement to make
I would say that it is poor statistics - a wild extrapolation from 2 examples.

Knowledge of life on Earth means we know about N=1 example.
- Statistics will tell you that if you have only 1 example, the standard deviation is undefined, so it gives you no clues about the chance of finding life on another planet.

Knowledge about life on Earth and Mars more than doubles the amount of information.
- But you shouldn't assume that 2/2 planets with life means that 100% of Earth-like planets will have life
- For example, statistics assumes that observations are independent. But we know meteorites have traveled between Earth and Mars, so they are not entirely independent.

N=2 is much more information than N=1.
- But N=10 (in different planetary systems) is a far better sample than N=2 in the same planetary system.
- Hopefully, some of the new generation of giant telescopes might give us some clues about atmospheres on distant planets.
Title: Re: Could there be life on other planets?
Post by: charles1948 on 21/02/2021 20:08:29

- But we know meteorites have traveled between Earth and Mars, so they are not entirely independent.


That's a good point.  Even if Martian rock-samples showed evidence of life, it might be argued that the life originated on Earth.  And was merely transferred to Mars by ancient meteorites which collided with Earth, and blasted bits of life-bearing Earth rocks to Mars.
Title: Re: Could there be life on other planets?
Post by: ukmicky on 21/02/2021 20:26:37
Which is the reason why the statement was so absurd especially when it was a NASA scientist who should know better.
Title: Re: Could there be life on other planets?
Post by: charles1948 on 21/02/2021 21:11:26
Which is the reason why the statement was so absurd especially when it was a NASA scientist who should know better.

NASA scientists probably do know better.  But they need to enthuse the public.  To get funding for future missions.
Title: Re: Could there be life on other planets?
Post by: Zer0 on 22/02/2021 20:32:56
Perhaps this OP was resurrected for the Good...

1) How old is planet Earth?

2) When did Life begin on this planet?

...Anyone?
🤔
Title: Re: Could there be life on other planets?
Post by: Kryptid on 22/02/2021 21:13:38
1) How old is planet Earth?

About 4.54 billion years according to current evidence.

2) When did Life begin on this planet?

The oldest known traces of life are about 3.7 billion years old, but life could have started even earlier.
Title: Re: Could there be life on other planets?
Post by: ukmicky on 24/02/2021 15:19:58

- But we know meteorites have traveled between Earth and Mars, so they are not entirely independent.


That's a good point.  Even if Martian rock-samples showed evidence of life, it might be argued that the life originated on Earth.  And was merely transferred to Mars by ancient meteorites which collided with Earth, and blasted bits of life-bearing Earth rocks to Mars.

As far as I’m aware the Martian rock only showed  signs of something that may have been life. So far it has never been determined if life has ever existed on Mars.
Title: Re: Could there be life on other planets?
Post by: Zer0 on 24/02/2021 17:56:10
@Kryptid
Thanks for being so prompt & answering to the point...
👍
Precision & Clarity Appreciated!
🙏

Now to take this further, step by step...

1) Would it be Wrong/Incorrect to hypothesize that Inanimate Objects/Matter took Less than a Billion years to come Alive?

2) Would it be an Error to Assume that Intelligent, Self Aware & Conscious life(say humans) took almost 3 billion years to evolve to a specific level of Science & Understanding?

&
3) Could there have been a Different anaerobic or silicon based or Entirely Different branch of Animate Life evolving parallely besides US during the first billion years which probably had No DNA/RNA specifics..could there be a possibility that happened..say a 00.00001% chance of MayBe that happened, but We do Not have any documented proofs for the same?

Anyone???
✌️
Title: Re: Could there be life on other planets?
Post by: ukmicky on 24/02/2021 19:08:53
@Kryptid
Thanks for being so prompt & answering to the point...
👍
Precision & Clarity Appreciated!
🙏

Now to take this further, step by step...


3) Could there have been a Different anaerobic or silicon based or Entirely Different branch of Animate Life evolving parallely besides US during the first billion years which probably had No DNA/RNA specifics..could there be a possibility that happened..say a 00.00001% chance of MayBe that happened, but We do Not have any documented proofs for the same?

Anyone???
✌️
it’s possible just like somewhere in the universe there is a planet called Traal which is inhabited by Ravenous Bugblatter Beasts.. 

I’m not making fun of your question because in theory just like there being a silicon based life form the above is possible and there is such a planet with such beasts but would you argue there was without any evidence .
Title: Re: Could there be life on other planets?
Post by: charles1948 on 24/02/2021 19:32:11
Zer0, you make valuable points in your post.

When we we look for evidence of "life" in the Universe, we may be taking an unduly "Carbon-centric" approach.

We're making the assumption that because Carbon is the basis of life on Earth, so it must be throughout the Universe.  But is this assumption justified. 

Other elements than Carbon, may have the potential to generate life.  An example is Silicon.

This element is the basis of all computers.  And don't these computers qualify as "living" beings?

They consume energy, in the form of electric current, excrete waste, in the form of excess heat, perform behaviours, such as running apps and displaying pixels on screens.  And reproduce themselves all over the planet.

Admittedly, they require a "host" to reproduce - in the form of Apple and other companies.  But does that disqualify them from being "alive".

Fleas and lice and viruses require hosts. 

Title: Re: Could there be life on other planets?
Post by: Kryptid on 24/02/2021 20:43:18
1) Would it be Wrong/Incorrect to hypothesize that Inanimate Objects/Matter took Less than a Billion years to come Alive?

It very probably did happen faster than that, yes.

2) Would it be an Error to Assume that Intelligent, Self Aware & Conscious life(say humans) took almost 3 billion years to evolve to a specific level of Science & Understanding?

At least 3.7 billion years, since we still trace our lineage back to the earliest microbes.

3) Could there have been a Different anaerobic or silicon based or Entirely Different branch of Animate Life evolving parallely besides US during the first billion years which probably had No DNA/RNA specifics..could there be a possibility that happened..say a 00.00001% chance of MayBe that happened, but We do Not have any documented proofs for the same?

It's certainly possible, but we don't have any evidence for it at the moment. That's not to say that couldn't change in the future. However, silicon-based life wouldn't be favorable on Earth. Silicon tends to lock itself up in highly-stable forms like minerals when exposed to oxygen. That doesn't tend to lend itself towards complex chemistry. There is far more silicon on Earth than carbon, and yet carbon-based life forms are the only ones we see.

One plausible alternative lineage of life I've seen proposed is "mirror" life, where the amino acids and carbohydrates are chirally-reversed from the life that we currently know of. It's possible that such life did exist early on, but that it became extinct and we are only have the version we see today. Or maybe abiogenesis somehow always produces our particular version of life for as-yet unknown reasons.
Title: Re: Could there be life on other planets?
Post by: bearnard1212 on 25/02/2021 13:38:37
Could there be life on other planets.

If you go by earths example then shouldnt the anwser be,unlikely.

The earth has been around for about 5 billion years, and yet life has only started here once, as all life on earth is related.

once in 5 billion years would mean life must be so hard to start in the first instance that maybe life on earth is just a fluke[:)]

There are also many other factors that have got be taken into account which has aided life and complex life on our planet to survive.

Like our position in our galaxy,our type and size of our sun and the fact that its not a binary. Jupiter handy for removing the odd comet that comes our way. the moon. the tilt of our planet very handy that. the size of our planet and its position in our solar system ,it's molten core , magnetisphere. oxygen nitrogen mix. the list could go on for ever.

May be our planet is unique and the life on it is unique. is it so unlikley that we are alone,could we be the first.[:)]

Michael                                      (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa186%2Fukmicky%2Frofl.gif&hash=481319b762ee9d57cda15e90d2e83ee6)
I assume that threr is a possibility that some sorts of life can exists on Mars. To be more accurate, scientists found frozen water on Mars.There is a possibility that we can find in that ice some sorts of life that existed on the red planet billions years ago.
Title: Re: Could there be life on other planets?
Post by: ukmicky on 25/02/2021 14:57:10
Could there be life on other planets.

If you go by earths example then shouldnt the anwser be,unlikely.

The earth has been around for about 5 billion years, and yet life has only started here once, as all life on earth is related.

once in 5 billion years would mean life must be so hard to start in the first instance that maybe life on earth is just a fluke[:)]

There are also many other factors that have got be taken into account which has aided life and complex life on our planet to survive.

Like our position in our galaxy,our type and size of our sun and the fact that its not a binary. Jupiter handy for removing the odd comet that comes our way. the moon. the tilt of our planet very handy that. the size of our planet and its position in our solar system ,it's molten core , magnetisphere. oxygen nitrogen mix. the list could go on for ever.

May be our planet is unique and the life on it is unique. is it so unlikley that we are alone,could we be the first.[:)]

Michael                                      (https://www.thenakedscientists.com/forum/proxy.php?request=http%3A%2F%2Fi11.photobucket.com%2Falbums%2Fa186%2Fukmicky%2Frofl.gif&hash=481319b762ee9d57cda15e90d2e83ee6)
I assume that threr is a possibility that some sorts of life can exists on Mars. To be more accurate, scientists found frozen water on Mars.There is a possibility that we can find in that ice some sorts of life that existed on the red planet billions years ago.
Yes it’s possible .

In my original post I said maybe life is so hard to start that it occurring on earth was a fluke . The logical answer to that is even if it was a fluke of nature it happening in the first instance allows for the right conditions to occur again.

 But it’s also possible that the conditions required are so unique (as we only have one example of it ever happening in over 3 billion years ) that a second occasion hasn’t occurred yet and this planet is still the only place in the universe with life .

Think about a 3 billion year plus experiment  that only returns evidence of one positive result .

To ignore the possibility that the earth is currently the only place in the universe with life which most seem to do isn’t very scientific when you consider the evidence ,or should I say the lack of evidence we have so far .


Ps, I’m not a fan of the quoting system we use on the forum.
Title: Re: Could there be life on other planets?
Post by: Zer0 on 25/02/2021 19:00:41

@charles1948
Even thou your thoughts or Your definition of " Life " might sound absurd & weird to others...
I cannot help but Agree with You!
👍

@Kryptid
Exactly what i expected...Bang on Target...Good Job!
👍

@bearnard1212
Very Good & Valid Assumption Indeed!
👍

@ukmicky
Perhaps We both are traveling on the same boat..in the same direction..Just that We both sit at opposite ends of the boat..& there is a brick walled sail between Us.
Hence, We are not able to see thru it & see each other as fellow travellers.
🙏

     As Important Evidence sounds to You...lemme Assure you, it is equally as important to me as well.
👍
Science without proof of evidence does not remain Science, but transcends into Religion.
✌️

We have different perspectives of looking at the same thing, just like different frames of reference.

IMHO...We have gathered half a glass of sample from the swimming pool...Others might Rightfully debate it ain't even half glass, more of like half a tablespoon out of the swimming pool.

Now...to discard the whole pool by simple assumption sayin, there ain't anything substantial in the collected sample...hence there won't be anything within the pool would be a lil egoistically careless of Us.
🙏
Please try to Understand..We need Evidence & Proofs..They Only way We would Obtain Or Relinquish them, is to look for them.
We won't find anything except our own ignorance, until & unless We do not Seek!
✌️
Title: Re: Could there be life on other planets?
Post by: yor_on on 25/02/2021 21:11:13
Yes, I think it's one of the main purposes of a universe. To create life. The thread is old but so is the question. Darwin had this idea of it starting in pools bathed in sunlight. It seems he might be correct.
Title: Re: Could there be life on other planets?
Post by: bearnard1212 on 28/05/2021 13:09:50
Rather interesting thread. That is a piece of good information. But still, we can only presume that life can exist there because these planets are too far. I think probably such space missions like James Webb Space Telescope the most expensive and the most advanced telescope by NASA or Ariel space telescope ( recently I found an article about that telescope  on a website  (https://arielmission.space/) ) and, it has the same purpose as James Webb Space Telescope to search for planets found beyond our solar system, otherwise known as exoplanets or extrasolar planets. I guess such technology will give us a hint at where life can exist and open more exoplanets.
https://en.wikipedia.org/wiki/James_Webb_Space_Telescope
Title: Re: Could there be life on other planets?
Post by: Zer0 on 28/05/2021 19:23:36
@bearnard1212


For some odd reason, You seem to be Transfixed with (SPAM)
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Just pure Enthusiasm i guess.
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Nice!



P.S. - i Hope Hidden Links & Shadowed URLs are being Checked/Verified constantly by the Mods.
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Title: Re: Could there be life on other planets?
Post by: CliffordK on 28/05/2021 19:48:23
Are any optical telescopes able to directly view exo planets?

Most of what we know about them has been looking at other phenomena including transits and interactions with stars.
Title: Re: Could there be life on other planets?
Post by: ukmicky on 28/05/2021 23:36:10
Yes, I think it's one of the main purposes of a universe. To create life. The thread is old but so is the question. Darwin had this idea of it starting in pools bathed in sunlight. It seems he might be correct.
Apart  from the need to conserve energy I don’t believe there is a purpose to the universe. I believe everything that has happened since day one has been the result of luck . Anything else would mean there would need to have been a basic pre written plan with a set  of rules .

But where could that plan have come from ,don’t say a cosmic planner.

Title: Re: Could there be life on other planets?
Post by: charles1948 on 29/05/2021 20:36:13
The Universe does seem to be governed by a set of rules. One particular rule should attract our attention:

The Pauli Exclusion Principle. Which proposes that no two electrons in an atom, can be in the same state or configuration at the same time.  This principle, when followed through, prevents all matter from collapsing into itself. So instead of the Universe vanishing within a nanosecond of its creation, it can continue to exist for billions of years.

The question is, where did the "Exclusion Principle" come from?  It doesn't seem an obvious kind of rule.  I mean, why shouldn't two electrons have the same state within an atom. What's wrong with that? Is seems natural enough.

Isn't the obvious answer,  that the exclusion principle is an unnatural rule.  Not arising from mere "luck".

But intentionally set up, in order to allow the Universe to exist long enough to develop life?

Title: Re: Could there be life on other planets?
Post by: Kryptid on 29/05/2021 20:49:53
Isn't the obvious answer,  that the exclusion principle is an unnatural rule.

I don't see how that's obvious at all. Something being unintuitive is not the same thing as being unnatural.
Title: Re: Could there be life on other planets?
Post by: charles1948 on 29/05/2021 21:03:00
Isn't the obvious answer,  that the exclusion principle is an unnatural rule.

I don't see how that's obvious at all. Something being unintuitive is not the same thing as being unnatural.

Yes, but it seems like something you wouldn't naturally expect.  Was it Fermi who complained, in another context involving the discovery of an unexpected new nuclear particle -  "Who ordered that?"
Title: Re: Could there be life on other planets?
Post by: Kryptid on 29/05/2021 21:25:32
A lot of scientific discoveries weren't expected.
Title: Re: Could there be life on other planets?
Post by: charles1948 on 29/05/2021 21:57:20
A lot of scientific discoveries weren't expected.

Yes, I think you nail the essential point.  Most scientists are content with existing long-established theories.  They don't like unexpected disruptions to the peaceful status quo.

So if an upstart scientist puts forward a new theory that disturbs the peace, he/she is likely to get hammered.

That's just human nature, isn't it?

Title: Re: Could there be life on other planets?
Post by: Professor Mega-Mind on 02/06/2021 14:34:03
Bulging-Skulls ,
Here's the thing ; life on Earth started just as soon as the red-hot rock cooled down , not 1-billion years after , not 4-billion years after , but immediately !
The likelihood then is that life is likely to gestate quickly , if the conditions are amenable .
Would the initial form be complete cells or even DNA ? Not a chance , as those would have to evolve from precursors .
The most likely candidate is a simple  protoprion , able to utilize the organic compounds abundant in the chemical stew that birthed it .
*It is of course , possible that this occurred on Mars , and then panspermia blasted the infestation over to Earth .
**The Martian Chronicles are we ! .🤓
Title: Re: Could there be life on other planets?
Post by: Kryptid on 02/06/2021 16:46:08
They don't like unexpected disruptions to the peaceful status quo.

Says who?

So if an upstart scientist puts forward a new theory that disturbs the peace, he/she is likely to get hammered.

Unless there is compelling evidence that the new theory is correct.
Title: Re: Could there be life on other planets?
Post by: Bored chemist on 02/06/2021 17:19:45
Isn't the obvious answer,  that the exclusion principle is an unnatural rule. 
If it's not from nature, where is it from?
Of course it's natural.