cyber_indian
Registered Senior Member
If there is any live form found in Stardust it will be "Archaea" ...
Stardust
- Thread starter cyber_indian
- Start date
I can't say if Archaea will be found in the sample brought by Stardust, but we'll know soon, because it has landed succesfully this morning
http://www.newscientistspace.com/article.ns?id=dn8586
It carries dust collected from the comet Wild 2
BTW, it's possible to use Stardust@home to analyze the sample
http://www.newscientistspace.com/article/dn8561
http://www.newscientistspace.com/article.ns?id=dn8586
It carries dust collected from the comet Wild 2
BTW, it's possible to use Stardust@home to analyze the sample
http://www.newscientistspace.com/article/dn8561
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Ophiolite
Valued Senior Member
One of the most important scientific and philosophical questions relates to the existence of life on other worlds. Allied to this is the Origin of Life: the means by which it occured and how commonplace it is.
There are some who are far removed from the beliefs of the Intelligent Design school and their appeal to irreducible complexity, and yet who are troubled by the emergence of simple life so rapidly after the formation of the Earth. To us the possibility of pan spermia has always been attractive.
If pan spermia is an effective and actual mechanism we should find life forms in the cometary dust. [Although there is a small get out clause - not all comets may originate in the same way and thus spores may not be found on each. ] If these are not found it will substantially destroy the argument for pan spermia, at least as it it typically understood.
What I would expect the analysis to show, regardless, is a range and diveristy of organic molecules, far, far beyond what has been detected to date by remote sensing.
There are some who are far removed from the beliefs of the Intelligent Design school and their appeal to irreducible complexity, and yet who are troubled by the emergence of simple life so rapidly after the formation of the Earth. To us the possibility of pan spermia has always been attractive.
If pan spermia is an effective and actual mechanism we should find life forms in the cometary dust. [Although there is a small get out clause - not all comets may originate in the same way and thus spores may not be found on each. ] If these are not found it will substantially destroy the argument for pan spermia, at least as it it typically understood.
What I would expect the analysis to show, regardless, is a range and diveristy of organic molecules, far, far beyond what has been detected to date by remote sensing.
Surely there is next to no chance that any form of life will be found in the comet dust collected by this probe. 
Organic molecules, probably. But life, I doubt it.
We can only speculate on the likelihood of extraterrestrial life in terms of life as we know it on Earth. Thus, in order for ET life to occur there needs to be liquid water (in addition to the raw materials required). In the near 0 Kelvin conditions of deep space this cannot happen. Surely life cannot arise <I>de novo</I> in deep space? So I was always under the impression that the only locations where ET life can evolve is on a solid planet with a temperature that allows liquid water.
Now, aren’t comets merely a loose collection of debris left over from solar system formation? They may have a solid nucleus but I didn’t think they had any heat from geothermal activity that would allow liquid water. Of course, Europa is thought to have liquid water underneath is frozen surface due to heat from the friction of the tidal forces from Jupiter rather than geothermal energy. But the same situation doesn’t apply to comets, does it? I imagine they heat up when they approach the Sun, but going from one temperature extreme to the other isn't very condusive for life.
As I see it, the concept of panspermia can occur only with meteorites – solid lumps of rock that contain life and that have been ejected from their planet by an impact, traveled through space and landed on another planet. We know this can happen because we have found Martian rocks on Earth. The only question is whether there was any Martian life in the countless Martian rocks that must have rained down on Earth during the early days of our solar system! It’s within the realms of possibility that we are all displaced Martians.
Anyway, planetary science isn't my strong suit, so I stand to be corrected on any of these issues.<P>
Organic molecules, probably. But life, I doubt it.We can only speculate on the likelihood of extraterrestrial life in terms of life as we know it on Earth. Thus, in order for ET life to occur there needs to be liquid water (in addition to the raw materials required). In the near 0 Kelvin conditions of deep space this cannot happen. Surely life cannot arise <I>de novo</I> in deep space? So I was always under the impression that the only locations where ET life can evolve is on a solid planet with a temperature that allows liquid water.
Now, aren’t comets merely a loose collection of debris left over from solar system formation? They may have a solid nucleus but I didn’t think they had any heat from geothermal activity that would allow liquid water. Of course, Europa is thought to have liquid water underneath is frozen surface due to heat from the friction of the tidal forces from Jupiter rather than geothermal energy. But the same situation doesn’t apply to comets, does it? I imagine they heat up when they approach the Sun, but going from one temperature extreme to the other isn't very condusive for life.
As I see it, the concept of panspermia can occur only with meteorites – solid lumps of rock that contain life and that have been ejected from their planet by an impact, traveled through space and landed on another planet. We know this can happen because we have found Martian rocks on Earth. The only question is whether there was any Martian life in the countless Martian rocks that must have rained down on Earth during the early days of our solar system! It’s within the realms of possibility that we are all displaced Martians.
Anyway, planetary science isn't my strong suit, so I stand to be corrected on any of these issues.<P>
Ophiolite
Valued Senior Member
You have accurately expressed the majority view on the matter. There are alternative views, that while not mainstream, are also not pseudo-science.
One aspect of the conventional origin of life hypotheses that I find troubling is the rapidity with which life appeared on Earth. Now it may well be that research in the next year, decade or century will reveal how this may have been achieved, but at the moment it is rather a lot of smoke and mirrors and altogether too few facts to satisfy me.
Within interstellar molecular clouds there will always be regions where temperatures are sufficient for liquid water (which I agree is likely to be a necessity for life). The attraction of a scenario in which life arises in this environment is that we have such a very much greater volume, by many orders of magnitude, within which the dice of chance can role on the roulette table of emergent properties.
A necessary prediction of such a view is a reasonable probability that cometary dust should contain life forms, not necessarily viable, but at least their complex remains. So, I am putting my cards on the table, as it were, and stating that if they are not found it is a rather large dent in this variant of pan spermia, and that the majority view looks like being correct.
Keep in mind that it is only a couple of decades since the notion of organic molecules in space was thought ridiculous, yet today we have detected them in several dozen varieties.
It may be that what will emerge from the analysis is the ambiguity of molecules normally associated with complex life, yet no definitive organisms. The smoke from the gun, but no gun.
If we only have roughly the same molecular types as have been detected to date I would view that as a substantial body blow.
One aspect of the conventional origin of life hypotheses that I find troubling is the rapidity with which life appeared on Earth. Now it may well be that research in the next year, decade or century will reveal how this may have been achieved, but at the moment it is rather a lot of smoke and mirrors and altogether too few facts to satisfy me.
Within interstellar molecular clouds there will always be regions where temperatures are sufficient for liquid water (which I agree is likely to be a necessity for life). The attraction of a scenario in which life arises in this environment is that we have such a very much greater volume, by many orders of magnitude, within which the dice of chance can role on the roulette table of emergent properties.
A necessary prediction of such a view is a reasonable probability that cometary dust should contain life forms, not necessarily viable, but at least their complex remains. So, I am putting my cards on the table, as it were, and stating that if they are not found it is a rather large dent in this variant of pan spermia, and that the majority view looks like being correct.
Keep in mind that it is only a couple of decades since the notion of organic molecules in space was thought ridiculous, yet today we have detected them in several dozen varieties.
It may be that what will emerge from the analysis is the ambiguity of molecules normally associated with complex life, yet no definitive organisms. The smoke from the gun, but no gun.
If we only have roughly the same molecular types as have been detected to date I would view that as a substantial body blow.
Really?Ophiolite said:
This is something I was never sure of. I had intuitively decided that this could not be the case for a cloud of gas floating around between stars. This has thrown a significant new variable into my way of thinking on this topic.Yes, I agree completely. But given the recent data that suggests that organic molecules could be abundant throughout the galaxy, it seems to me that a hybrid of the two extremes is just as likely as either panspermia or <I>de novo</I> chemistry as the source of life on Earth. The numerous impacts that occurred during the Earth’s first 500 million years or so might have seeded the new planet with huge amounts of organic molecules. Perhaps this accelerated the formation of life, a process that might have taken significantly longer in the absence of these raw materials.<P>Ophiolite said:
Ophiolite
Valued Senior Member
I confess I have somewhat gone out on a limb with my statement on the temperature within GMCs (Giant Molecular Clouds). I have seen no research that declares this to be the case, (but equally none that says it is not). It just seems reasonable to me that within zone of gravitational collapse that are potential stars/planetary systems in the making there must be extensive areas of suitable temperature. Moreover within these one would expect some planetesimals of cometary type to coalesce. Within these gravitational and perhaps radioactive heating should produce a zone within the body harbouring liquid water and very likely a rich mix of organics.
Of course this is all hypothetical. The beauty is that it is readily falsified. (Well, given some time.) The Stardust mission certainly affords such an opportunity.
I normally stay in the closet on this subject since frankly I am not well enough versed in all the details to offer anything like an expert opinion. However, this sample return offers a real chance of providing evidence in one or other direction.
I am certain, as you say, that if life did originate on Earth it got one hell of a kick start from interstellar organic molecules. A side note on this: a couple of years ago I read some research on experiments with impact forces and amino acids. The researchers wanted to see if the amino acids could survive the sort of impact to be expected from cometary strikes on the Earth when embedded in the comet. Or would they get disociated into simpler moelcules? To their surprise the amino acids not only remained intact, but they linked up to form polypeptides, the forerunners of proteins. Damnably, I have lost the reference to the research, so I cant offer a link.
Of course this is all hypothetical. The beauty is that it is readily falsified. (Well, given some time.) The Stardust mission certainly affords such an opportunity.
I normally stay in the closet on this subject since frankly I am not well enough versed in all the details to offer anything like an expert opinion. However, this sample return offers a real chance of providing evidence in one or other direction.
I am certain, as you say, that if life did originate on Earth it got one hell of a kick start from interstellar organic molecules. A side note on this: a couple of years ago I read some research on experiments with impact forces and amino acids. The researchers wanted to see if the amino acids could survive the sort of impact to be expected from cometary strikes on the Earth when embedded in the comet. Or would they get disociated into simpler moelcules? To their surprise the amino acids not only remained intact, but they linked up to form polypeptides, the forerunners of proteins. Damnably, I have lost the reference to the research, so I cant offer a link.
cyber_indian
Registered Senior Member
in order for ET life to occur there needs to be liquid water (in addition to the raw materials required) - Hercules Rockefeller Do you have any idea what Archaea is ? Do you know that can live on methane for instance, live in rocks under enourmous PSI, live in extreme heat or cold, or live on radiation 1500x that human will die on.
Surely life cannot arise de novo in deep space - why not ?
the two extremes is just as likely as either panspermia or de novo chemistry as the source of life on Earth - Why not both of them ?
Or world could only be what we have wrote in our books.
Surely life cannot arise de novo in deep space - why not ?
the two extremes is just as likely as either panspermia or de novo chemistry as the source of life on Earth - Why not both of them ?
Or world could only be what we have wrote in our books.
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Yes, I have a very good idea.cyber_indian said:
Yes, I am well aware of this. What’s your point?cyber_indian said:
I said why. The formation of life requires liquid water. Once that life has formed it will be capabale of adapting and evolving to cope with all various environmental conditions you mention, including a subsequent absence of water.cyber_indian said:
That’s precisely what I did say.<P>cyber_indian said:
DwayneD.L.Rabon
Registered Senior Member
Here is a list of the atoms and there polar response, atoms marked CS are responsive to the cosmic background(cosmis sensitive), those marked GS are galaxtic sensitive and those SS are solar sensitive.
The support sturcture of humans is entirely SS, you can equate the atoms of the chart in there group with there function in the human body or other life on our planet to asses how there senstiveibty organizes to form life.
In general any of the SS group would act as a support for life, subject to abundance and selection.
If the satilite STARDUST has brought back life from a comet, i would have to assume that such life was based on a heavy atom, given the chart the defintion of tungsten seems to be near that of carbon, and in a atmosphere with the lack of gravity tungsten therefor seems like it would be the choice element for life on a coment, however i have no idea of the precentage of tungesten found in coments.
The chart appllies through out the Galaxy, for example you can exspect that the support structure of a life form in our galaxy to fall in the SS group, and the medium of such a life form, meaning fluid, transfereing fluids,chemical lift to fall in the CS group.
THE GALAXTIC PERIODIC CHART OF THE ELEMENTS, by DwayneD.L.Rabon
CS -16 ARGON
CS 2.660 BROMINE (GS)
CS 1.720 CHLORINE
CS -47 FLOURINE
CS -99 HELIUM
CS -86 HYDROGEN
CS 1.160 KRYPTON
CS 2.330 MERCURY (GS)
CS -75 NEON
CS -37 NITROGEN
CS -45 OXYGEN
CS 2.020 RADON (GS)
CS 1.620 XENON
GS 9.330 ALUMINIUM
GS 9.030 ANTIMONY
GS 8.090 ARSENIC
GS 5.750 ASTATINE
GS 10.00 BARIUM
GS 8.150 BISMUTH
GS 5.940 CADMIUM
GS 10.71 CERIUM (SS)
GS 3.010 CESIUM
GS 10.95 EUROPIUM (SS)
GS 3.000 FRANCIUM
GS 3.020 GALLIUM
GS 4.290 INDIUM
GS 3.860 IODINE
GS 6.000 LEAD
GS 4.530 LITHIUM
GS 9.230 MAGNESIUM
GS 9.170 NEPTUNIUM
GS 3.170 PHOSPHORUS
GS 9.130 PLUTONIUM
GS 5.270 POLONIUM
GS 3.360 POTASSIUM
GS 9.730 RADIUM
GS 3.120 RUBIDIUM
GS 4.530 SELENIUM
GS 3.700 SODIUM
GS 10.50 STRONTIUM (SS)
GS 3.860 SULFUR
GS 7.220 TELLURIUM
GS 5.770 THALLIUM
GS 5.040 TIN
GS 10.92 YTTERBIUM (SS)
GS 6.920 ZINC
SS 13.24 ACTINIUM
SS 14.49 AMERICIUM
SS 13.23 BERKELIUM
SS 15.60 BERYLLIUM
SS 23.48 BORON
SS 11.15 CALCIUM
SS 11.73 CALIFORNIUM
SS 37.73 CARBON
SS 21.80 CHROMIUM
SS 17.68 COBALT
SS 13.57 COPPER
SS 16.18 CURIUM
SS 16.85 DYSPROSIUM
SS 11.33 EINSTENIUM
SS 18.02 ERBIUM
SS 18.00 FERMIUM
SS 15.86 GADOLINIUM
SS 12.11 GERMANIUM
SS 13.37 GOLD
SS 25.06 HAFNIUM
SS 17.47 HOLMIUM
SS 27.19 IRIDIUM
SS 18.11 IRON
SS 11.91 LANTHANIUM
SS 19.00 LAWRENCIUM
SS 19.36 LUTETIUM
SS 15.19 MANGANESE
SS 11.00 MENDELEVIUM
SS 28.96 MOLYBDENUM
SS 12.94 NEODYMIUM
SS 17.28 NICKEL
SS 27.50 NIOBIUM
SS 11.00 NOBELIUM
SS 33.06 OSMIUM
SS 18.27 PALLADIUM
SS 20.41 PLATINUM
SS 12.04 PRASEODYMIUM
SS 13.15 PROMETHIUM
SS 18.45 PROTACTINIUM
SS 34.59 RHENIUM
SS 22.37 RHODIUM
SS 27.07 RUTHENIUM
SS 13.47 SAMARIUM
SS 18.14 SCANDIUM
SS 16.87 SILICON
SS 12.34 SILVER
SS 32.90 TANTALUM
SS 24.30 TECHNETIUM
SS 16.29 TERBIUM
SS 20.23 THORIUM
SS 18.18 THULIUM
SS 19.41 TITANIUM
SS 36.95 TUNGSTEN
SS 14.08 URANIUM
SS 21.83 VANADIUM
SS 17.95 YTTRIUM
SS 21.28 ZIRCONIUM
% Precentages of the earths crust/ earth
Oxygen 46.43% CS
Silicon 27.77% SS
Aluminum 8.14% GS
Iron 5.12% SS
Calcium 3.62% SS
Magnesium 2.09% GS
Sodium 2.85% GS
Potassium 2.60% GS
Hydrogen 0.127% CS
The other 83 elements 1.253%
Earth is
46.557 % Cosmic Sensitive
15.68% Galaxtic Sensitive
36.51% Solar Sensitive
Galaxtic Periodic Elements , By DwayneD.L.Rabon
DwyaneD.L.Rabon
The support sturcture of humans is entirely SS, you can equate the atoms of the chart in there group with there function in the human body or other life on our planet to asses how there senstiveibty organizes to form life.
In general any of the SS group would act as a support for life, subject to abundance and selection.
If the satilite STARDUST has brought back life from a comet, i would have to assume that such life was based on a heavy atom, given the chart the defintion of tungsten seems to be near that of carbon, and in a atmosphere with the lack of gravity tungsten therefor seems like it would be the choice element for life on a coment, however i have no idea of the precentage of tungesten found in coments.
The chart appllies through out the Galaxy, for example you can exspect that the support structure of a life form in our galaxy to fall in the SS group, and the medium of such a life form, meaning fluid, transfereing fluids,chemical lift to fall in the CS group.
THE GALAXTIC PERIODIC CHART OF THE ELEMENTS, by DwayneD.L.Rabon
CS -16 ARGON
CS 2.660 BROMINE (GS)
CS 1.720 CHLORINE
CS -47 FLOURINE
CS -99 HELIUM
CS -86 HYDROGEN
CS 1.160 KRYPTON
CS 2.330 MERCURY (GS)
CS -75 NEON
CS -37 NITROGEN
CS -45 OXYGEN
CS 2.020 RADON (GS)
CS 1.620 XENON
GS 9.330 ALUMINIUM
GS 9.030 ANTIMONY
GS 8.090 ARSENIC
GS 5.750 ASTATINE
GS 10.00 BARIUM
GS 8.150 BISMUTH
GS 5.940 CADMIUM
GS 10.71 CERIUM (SS)
GS 3.010 CESIUM
GS 10.95 EUROPIUM (SS)
GS 3.000 FRANCIUM
GS 3.020 GALLIUM
GS 4.290 INDIUM
GS 3.860 IODINE
GS 6.000 LEAD
GS 4.530 LITHIUM
GS 9.230 MAGNESIUM
GS 9.170 NEPTUNIUM
GS 3.170 PHOSPHORUS
GS 9.130 PLUTONIUM
GS 5.270 POLONIUM
GS 3.360 POTASSIUM
GS 9.730 RADIUM
GS 3.120 RUBIDIUM
GS 4.530 SELENIUM
GS 3.700 SODIUM
GS 10.50 STRONTIUM (SS)
GS 3.860 SULFUR
GS 7.220 TELLURIUM
GS 5.770 THALLIUM
GS 5.040 TIN
GS 10.92 YTTERBIUM (SS)
GS 6.920 ZINC
SS 13.24 ACTINIUM
SS 14.49 AMERICIUM
SS 13.23 BERKELIUM
SS 15.60 BERYLLIUM
SS 23.48 BORON
SS 11.15 CALCIUM
SS 11.73 CALIFORNIUM
SS 37.73 CARBON
SS 21.80 CHROMIUM
SS 17.68 COBALT
SS 13.57 COPPER
SS 16.18 CURIUM
SS 16.85 DYSPROSIUM
SS 11.33 EINSTENIUM
SS 18.02 ERBIUM
SS 18.00 FERMIUM
SS 15.86 GADOLINIUM
SS 12.11 GERMANIUM
SS 13.37 GOLD
SS 25.06 HAFNIUM
SS 17.47 HOLMIUM
SS 27.19 IRIDIUM
SS 18.11 IRON
SS 11.91 LANTHANIUM
SS 19.00 LAWRENCIUM
SS 19.36 LUTETIUM
SS 15.19 MANGANESE
SS 11.00 MENDELEVIUM
SS 28.96 MOLYBDENUM
SS 12.94 NEODYMIUM
SS 17.28 NICKEL
SS 27.50 NIOBIUM
SS 11.00 NOBELIUM
SS 33.06 OSMIUM
SS 18.27 PALLADIUM
SS 20.41 PLATINUM
SS 12.04 PRASEODYMIUM
SS 13.15 PROMETHIUM
SS 18.45 PROTACTINIUM
SS 34.59 RHENIUM
SS 22.37 RHODIUM
SS 27.07 RUTHENIUM
SS 13.47 SAMARIUM
SS 18.14 SCANDIUM
SS 16.87 SILICON
SS 12.34 SILVER
SS 32.90 TANTALUM
SS 24.30 TECHNETIUM
SS 16.29 TERBIUM
SS 20.23 THORIUM
SS 18.18 THULIUM
SS 19.41 TITANIUM
SS 36.95 TUNGSTEN
SS 14.08 URANIUM
SS 21.83 VANADIUM
SS 17.95 YTTRIUM
SS 21.28 ZIRCONIUM
% Precentages of the earths crust/ earth
Oxygen 46.43% CS
Silicon 27.77% SS
Aluminum 8.14% GS
Iron 5.12% SS
Calcium 3.62% SS
Magnesium 2.09% GS
Sodium 2.85% GS
Potassium 2.60% GS
Hydrogen 0.127% CS
The other 83 elements 1.253%
Earth is
46.557 % Cosmic Sensitive
15.68% Galaxtic Sensitive
36.51% Solar Sensitive
Galaxtic Periodic Elements , By DwayneD.L.Rabon
DwyaneD.L.Rabon
cyber_indian
Registered Senior Member
Who said that there is no water on commets and evlolving ... the idea is to use comets as transfering medium or also known as vectors and preservation. Plus did I mention that some Archaea do cell division once every hundred years.
About panspermia...
I personally doubt whether life did begin in interstellar clouds as I assume they would have a lack of large surfaces on which organic molecules can accumulate. (I appreciate that the total surface area of all those dust particles in any given nebula would be huge.)
Anyway, perhaps there are some people who haven't seen this article about possible evidence for panspermia in India.
I personally doubt whether life did begin in interstellar clouds as I assume they would have a lack of large surfaces on which organic molecules can accumulate. (I appreciate that the total surface area of all those dust particles in any given nebula would be huge.)
Anyway, perhaps there are some people who haven't seen this article about possible evidence for panspermia in India.
cyber_indian
Registered Senior Member
Panspermia isn't intrested in creation of live, but its continuation and it's mechanisms ...
If life did originate on a planet's surface, presumably the only way it could reach space would be by catching a lift within ejecta. Or is there another way? If blasted rock is the only method for producing single-celled astronauts, then am I right in thinking that the fragment will need some outrageously lucky interactions with large planets if it is to enter interstellar space?
Even though the universe is exceedingly large, exceedingly old, and probably witnesses an exceedingly large number of planetary impacts, I tend to believe that life is not exceedingly common. So I don't see how panspermia is feasible if life's origins are assumed to be planetary.
Even though the universe is exceedingly large, exceedingly old, and probably witnesses an exceedingly large number of planetary impacts, I tend to believe that life is not exceedingly common. So I don't see how panspermia is feasible if life's origins are assumed to be planetary.
Laika,
The article you linked to is astounding if I read the abstract correctly. These scientists claim to have cells that may have originated in a cometary body? And rained down on earth??? I never heard even a hint of this. What's up with this?
The article you linked to is astounding if I read the abstract correctly. These scientists claim to have cells that may have originated in a cometary body? And rained down on earth??? I never heard even a hint of this. What's up with this?
It is astounding. I don't have the expertise to comment on the biology or the atmospheric physics of it, but they've got some heavy-looking sums in there. It's a shame that the cometary break-up to which they attribute the scattering of the 'cells' was not actually witnessed, but rather was inferred from the loud bang. Also, the 'cells' apparently don't contain any DNA. I don't know how significant this would be if it was truly alien life, but according to the panspermia theory I thought that all life in the galaxy ought to be based on the same fundamental building blocks.
Ophiolite
Valued Senior Member
Superluminal, google for the work of Fred Hoyle and Chandra Wickramasinghe. They are (were in the case of Hoyle, who is now dead) convinced of the strong possiblity of life originating in space. (Not on planetary surfaces, Laika.)
The calculations for safe removal of viable cells via ejecta have been done for Mars sized bodies and it is no great problem.
Earthly germs survived two or three years on the Ranger robot probe on the surface of the Moon, subject to violent temperature fluctuations and exposure to regular solar radiation, solar flares and cosmic rays.
The mainstream scientific community do not like the notion. However, over the last coupld of decades they have been forced to move their position close to that of Hoyle. One clear example - Hoyle et al predicted comets would be rich in organic chemicals. They are. So much so that many of them are quite dark. The range and complexity of organic molecules being detected in deep space is steadily increasing.
We could be in for the biggest paradigm shift since the Big Bang replaced Steady State (another Hoyle idea - indeed Hoyle coined the phrase Big Bang in order to poke fun at the concept. Increasingly it looks like he was right to do so, but that is another story.)
The calculations for safe removal of viable cells via ejecta have been done for Mars sized bodies and it is no great problem.
Earthly germs survived two or three years on the Ranger robot probe on the surface of the Moon, subject to violent temperature fluctuations and exposure to regular solar radiation, solar flares and cosmic rays.
The mainstream scientific community do not like the notion. However, over the last coupld of decades they have been forced to move their position close to that of Hoyle. One clear example - Hoyle et al predicted comets would be rich in organic chemicals. They are. So much so that many of them are quite dark. The range and complexity of organic molecules being detected in deep space is steadily increasing.
We could be in for the biggest paradigm shift since the Big Bang replaced Steady State (another Hoyle idea - indeed Hoyle coined the phrase Big Bang in order to poke fun at the concept. Increasingly it looks like he was right to do so, but that is another story.)
Simple life is probably very common. I.e. better than a 50/50 chance on at least one orbiting object in every solar system.Laika said:
To advance to more complex, but still single-cell forms (Those with considerable internal structures providing unique services to the organism.) is highly probable at least on thousands of objects in each galaxy.
I suspect simple multiple-cell creature have better than 50/50 chance of existing at least on one object in each galaxy, but something as complex as an earthworm, I believe has much less than a 50/50 chance to exist even at the one per galaxy rate.
It is far too much pure speculation to guess what is the chance that other creatures of human complexity, with self awareness, consciousness, etc, exist in the universe, but if they do at the present time, I think it highly likely that they are more inteligent and capable than humans, who also will be much more so in less than 100,000 years, if they can manage to survive that long, which I doubt.
For more infromation search: Habital zone.
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