life is prevalent throughout the universe

[voidpotentialenergy]

I think the occurrence of little planets with huge moons may be much more common that we could think at first sight. Only in our solar system we have Earth/Moon and Pluto/Charon, and for what we are starting to know about the genesis of solar systems the collisions between planets and protoplanets in the beginning of this process could be quite common.
Also, the claim that a big moon could be necessary for the evolution of sentient life seems to me too anthropocentric to be seriously considered.
We have also discovered many gas giants in the Goldilock zone of their stars that could have habitable moons.
So, the places in which complex lifeforms can evolve could be very common in our galaxy.
But the occurrence of sentient life cannot be evaluated in those terms.
In fact, the origin of life is a chemical process, deterministic for its nature, while the evolution is an historical process that happens in a completely random way, resulting from the interaction between genetic variabilty and environmental variables, so we cannot use statistic instruments to estimate if the arise of a sentient species may be common or rare.
Moreover, is also impossible to predict the possibility that a sentient species not living in an aquatic environment could develop a technological civilization,

I think earth moon system will be quite rare.
The bulk of the Earth/mars collision that made ours will result in no world at all.

Not saying they won't exist just saying they will be maybe 1 in a million sort of event and most of the 1 in a million the moon will be to big or to small.

Getting rid of all the stars in our galaxy that live in supernova country as potentials we might be left with just the whispy arms of the galaxy that long term life can exist
Maybe a few billion stars that 95+% are not correct star type or quiet flare type.

Alone might be an understatement.

Life Probably in as many places as it can be, but just basic life.

 

[voidpotentialenergy]

The bottom line is that we have no definite knowledge whatsoever of life other than on Earth.

Everything else is speculation or extravagant imagination.

Cat

For sure we have no clue about the % of life happening.
If it isn't a pretty common thing we should get used to the fact that we might be it in our galaxy or it for many many galaxies other than basic life in random place.
difficult to shake hand with slime mold

 

[Catastrophe]

VPE
"The probability of an earthlike world colliding with a mars like world and ending up with a big moon and Earthlike world is not good."

I do agree with you and 'like' your post. I do not disagree.

However, there are other possibilities, such as the two moons of Mars.
And before you jump (quite rightly) to tell me that these are tiny, probably captured asteroids, I must insist (unless I have missed something, for which I apologise if so) that pending revision of nomenclature, these are currently termed moons.

Asteroid Belts may, or may not, be common, but there are other possibilities for moons, or even planets (think also of dwarf planets) such as arrival of TNAs (objects from beyond Neptune) and other categories of distant object to arrive in the inner Solar System.

So, whilst I would agree with you about:
"The probability of an earthlike world colliding with a mars like world and ending up with a big moon and Earthlike world is not good."
I suggest that you have chosen as example probably the least likely mechanism.

Cat
P.S. I do appreciate that planets or moons of a certain size are necessary, and that your example, whilst describing a rare occurrence, does fit this.

 

[Catastrophe]

life is prevalent throughout the universe - is our heading.

Without further complicating the previous post, I will just point out that there are plenty of suggestions about (future) life on some moons of Jupiter, Saturn and Neptune - some of these moons being considerably smaller than our Moon which you described (correctly) in your example.

Cat
P.S. Order of objects in our SS below Mars, in decreasing order:
Ganymede
Titan
Mercury
Callisto
Io
Moon
Europa
Triton
Pluto / Eris (similar).

 

[Trevize62]

The probability of an earthlike world colliding with a mars like world and ending up with a big moon and Earthlike world is not good.
Just a small change in that impact angle and we end up with no world at all.

Maybe a 1 in a million collision then each needs to be left with just the right amount of stuff of the right type of materials going around the right type of star at the right type of distance with freak events that bring water to a planet that formed in a dry location.

See how fast the odds get bad.
To big of a moon and we get gigantic tides and crazy weather, to small and we get a planet that wobbles it's poles making it very difficult for land life to evolve.

Big moons even in our solar system are pretty high in number and well protected and in stable orbits for long term life development.
Put Saturn or Jupiter in the goldilocks zone and we end up with multiple moons with a decent chance with lots of water already.

Given the number of solar systems in our galaxy, also 1 in a million means a many "useful" collisions. But are we sure that a huge moon is a conditio sine qua non for the development of intelligent life on a planet?
I remember you that we have not yet detected any extraterrestrial lifeform, and also that there is no limit in what the evolution can produce, so every possibility remains opened, including that Earth may be the only planet in our galaxy hosting complex lifeforms.

 

[voidpotentialenergy]

VPE
"The probability of an earthlike world colliding with a mars like world and ending up with a big moon and Earthlike world is not good."

I do agree with you and 'like' your post. I do not disagree.

However, there are other possibilities, such as the two moons of Mars.
And before you jump (quite rightly) to tell me that these are tiny, probably captured asteroids, I must insist (unless I have missed something, for which I apologise if so) that pending revision of nomenclature, these are currently termed moons.

Asteroid Belts may, or may not, be common, but there are other possibilities for moons, or even planets (think also of dwarf planets) such as arrival of TNAs (objects from beyond Neptune) and other categories of distant object to arrive in the inner Solar System.

So, whilst I would agree with you about:
"The probability of an earthlike world colliding with a mars like world and ending up with a big moon and Earthlike world is not good."
I suggest that you have chosen as example probably the least likely mechanism.

Cat
P.S. I do appreciate that planets or moons of a certain size are necessary, and that your example, whilst describing a rare occurrence, does fit this.

Trouble with mini worlds just colliding with each other is we end up with a small iron core or they blast each other or no spin etc etc.
I think we are stuck with glancing blows to create an earth and moon.

Probably lots of ways to create a moon/earth combo but terrestrial planets tend to form in locations that water is in small quantity.
We also need some big shifts in bigger planets to migrate water to them without gobbling them up in the move.

I think we end up with most earthlike or even earth/moon systems as dry places heading towards a Venus soft of planet.

I think lots of people looking at the galaxy forget that 90% of the start are the wrong type and 90%of the remaining are in supernova country.
Then all the freak happenings in our solar system to move water, set Jupiter and Saturn in sync orbits before they ate everything.
Then all the lucky mix of metal/silicon/water and a big moon on a freak collision in just the right place around a perfect quiet star.
Then life starting pretty much ASAP to alter our world away from Venus.

If this was a poker hand i would fold LOL

We cross out many of these needs on Moons of robust planets.

 

[voidpotentialenergy]

life is prevalent throughout the universe - is our heading.

Without further complicating the previous post, I will just point out that there are plenty of suggestions about (future) life on some moons of Jupiter, Saturn and Neptune - some of these moons being considerably smaller than our Moon which you described (correctly) in your example.

Cat
P.S. Order of objects in our SS below Mars, in decreasing order:
Ganymede
Titan
Mercury
Callisto
Io
Moon
Europa
Triton
Pluto / Eris (similar).

Yes many many moons that already have a magnetic protector and water.
I expect the universe will be full of them in just the right place.
Even our solar system with an orbit change and a few are possible water worlds.

 

[Catastrophe]

VPE
"Then all the lucky mix of metal/silicon/water and a big moon on a freak collision in just the right place around a perfect quiet star."

Don't forget that we are constrained by the proportion of elements throughout the Universe.

After the hydrogen and helium which occur primarily in stars, silicon and oxygen (partly making silica) will be very common in any non-solar bodies (exceptions being remnants from cores of broken asteroids).

Cat

 

[Catastrophe]

VPE
"Trouble with mini worlds just colliding with each other is we end up with a small iron core or they blast each other or no spin etc etc."

I agree, but smaller ones are not dependent on collisions like the larger Earth/Moon system. I am thinking of Titan/Triton/Enceladus types which may not blossom until the Sun expands in about 5by time.

Cat

 

[voidpotentialenergy]

Given the number of solar systems in our galaxy, also 1 in a million means a many "useful" collisions. But are we sure that a huge moon is a conditio sine qua non for the development of intelligent life on a planet?
I remember you that we have not yet detected any extraterrestrial lifeform, and also that there is no limit in what the evolution can produce, so every possibility remains opened, including that Earth may be the only planet in our galaxy hosting complex lifeforms.

The galaxy is vast and full of stars but the vast majority are living in supernova country.
Life on any of the worlds that experience a supernova with 20ly will be sterilized or even the planet stripped of atmosphere.

Whispy arms of the galaxy IMO are the only place for life to take hold.
In total a few billion stars and of them 95% Wrong type/not quiet activity/double tripple systems .

We might end up with 1 million possible stars for long term life.
! in 100 have an earth in the right place.
1 in 100 of those don't become Venus because life starts ASAP.
1 in 100 of those have the right silicon/metal/water mix
1 in 100 of those have a big moon.
Lots of freak events beyond this for us to arrive.

IMO we will have millions times earth/moon of moons around robust planets in just the right place and be able to shorten the checklist a lot.

Big robust worlds are great protectors and tidal lock stoppers of the moons that orbit them so red dwarfs could become possible places for life opening a vast new number of the few billion possible stars in the whispy arms.

 

[Catastrophe]

VPE
"We also need some big shifts in bigger planets to migrate water to them without gobbling them up in the move."

There is apparently abundant water in Titan/Triton/Enceladus type moons. Again, may have to wait to be warmed by Solar expansion in about 5 billion years.

Cat

 

[Catastrophe]

VPE
You are correct in saying that the Universe is a dangerous place.

Cat

 

[voidpotentialenergy]

VPE
"Then all the lucky mix of metal/silicon/water and a big moon on a freak collision in just the right place around a perfect quiet star."

Don't forget that we are constrained by the proportion of elements throughout the Universe.

After the hydrogen and helium which occur primarily in stars, silicon and oxygen (partly making silica) will be very common in any non-solar bodies (exceptions being remnants from cores of broken asteroids).

Cat

Yep I'm not waiting for ET to call. LOL
Wet worlds in the right place i think will be freakish.
Most i think will be copies of Venus.

Nothing we can do about what earth got other than thank our lucky star it was just this and that in perfect amounts, then thank Jupiter/Saturn moving around for the water.

Got to make you wonder how alone we could be in our galaxy or even in the entire universe.

 

[Catastrophe]

The prevalence of (intelligent) life is one thing. The ability of intelligent life, even if present on 10% of all stars' planets (which I agree is extremely unlikely) to communicate is another question entirely. Vide Alpha Centauri.

Sorry about the bold. The sentence became somewhat cumbersome.

Cat

 

[voidpotentialenergy]

The prevalence of (intelligent) life is one thing. The ability of intelligent life, even if present on 10% of all stars' planets (which I agree is extremely unlikely) to communicate is another question entirely. Vide Alpha Centauri.

Sorry about the bold. The sentence became somewhat cumbersome.

Cat

Totally agree, even if we got lucky and found a tech society in our galaxy the communication and life span of each has got to be pretty short.
Even if we endure a few million year we could miss our neighbor being alive billions of years.

Hope life is a pretty typical happening in the galaxy but we should be happy either way to think we might be what spreads life to the universe.
What a noble mission we have.

 

[Catastrophe]

life is prevalent throughout the universe

When you consider the billions upon billions of galaxies (many in parts of the Universe not visible to us - and probably never to be visible to us) and the billions upon billions upon billions of planets - it is, in my view, an absolute certainty that there are at least millions of cases of intelligent life (and billions that have been and will be) and billions of cases of simple life forms.

Cat

 

[Trevize62]

I wouldn't say "weird". Half the planets in the solar system tilt between 20° and 30°. Two others are WAY off kilter (Venus 177° and Uranus 98°)


That being a relative term. If they have Gort, we mean nothing to them.


Supposedly, the majority of solar systems are binary or even tri-star systems. Our could be the odd-ball worth looking at.


I'd call us "Off the beaten path!"


If we're lucky, we'll get the Greys. If not, the Yautja bringing Xenomorphs for hunting.

-Wolf sends

Do not forget Daleks or Borgs.

 

[Helio]

life is prevalent throughout the universe

When you consider the billions upon billions of galaxies (many in parts of the Universe not visible to us - and probably never to be visible to us) and the billions upon billions upon billions of planets - it is, in my view, an absolute certainty that there are at least millions of cases of intelligent life (and billions that have been and will be) and billions of cases of simple life forms.

Cat

I'm gonna say that you will only be off by millions, but I just can't say which way! *wink*

 

[Trevize62]

I'm gonna say that you will only be off by millions, but I just can't say which way! *wink*

The evolution doesn't function in this way. The appearance of a determinate characteristic in a lifeform is completely random and cannot be estimated statistically.
The law of big numbers can be predictive of the frequency of the phenomenon life in itself, because its appearance, even if not yet understood, is clearly the result of a chemical process that can occur wherever certain condition are present, but no predictions can be made about the way in which lifeforms can evolve on Earth or every other Earth-like planet or moon.
Also, we don't have an univocal concept of intelligence in humans and this concept itself could be an aprioristic assert based on our prejudices.

 

[Helio]

The evolution doesn't function in this way. The appearance of a determinate characteristic in a lifeform is completely random and cannot be estimated statistically.

Yes, which in a universe with roughly 1E23 stars, and possibly planets, any actual guess as to the number intelligent life planets will be a wild one. This is the best we can do given a data set of only one point. Time will improve how we address the terms in the Drake Equation. Discovering other planets was a major step.

The law of big numbers can be predictive of the frequency of the phenomenon life in itself, because its appearance, even if not yet understood, is clearly the result of a chemical process that can occur wherever certain condition are present, but no predictions can be made about the way in which lifeforms can evolve on Earth or every other Earth-like planet or moon.

Yes, it is a good reminder that evolution is a passive process, whereas we too often use that term when applied to our active process use. It's why Darwin called Lord Kelvin and "odious specter" when less than 100 million years was deemed by LK as the age of the Earth. Darwin wanted, IIRC, at least a billion years.

But the idea of frequency at this point (pun warning) is, well, almost pointless given only one data point - Earth.

 

[Trevize62]

Yes, which in a universe with roughly 1E23 stars, and possibly planets, any actual guess as to the number intelligent life planets will be a wild one. This is the best we can do given a data set of only one point. Time will improve how we address the terms in the Drake Equation. Discovering other planets was a major step.


Yes, it is a good reminder that evolution is a passive process, whereas we too often use that term when applied to our active process use. It's why Darwin called Lord Kelvin and "odious specter" when less than 100 million years was deemed by LK as the age of the Earth. Darwin wanted, IIRC, at least a billion years.

But the idea of frequency at this point (pun warning) is, well, almost pointless given only one data point - Earth.

I think also that Drake's equation is a nonsense.

 

[Catastrophe]

I think also that Drake's equation is a nonsense.

I do agree that it is a succession of variables (to be multiplied together) each of which is an inspired (or uninspired) guess. This is not to say that the input variables cannot be refined over time.

Cat

 

[marty369]

I've been reading through all the posts on this thread and there are some very interesting comments, factual statistics and points of view but i have noticed that we homo sapien sapiens as intelligent and advanced as we are at this moment are still very limited in our thinking and quite close minded about how we process our thoughts and if something doesn't make sense to us then it's either wrong, insane or is just far to mind boggling to comprehend so isn't worth pursuing with logical scientific thoughts and studies but we don't really know anything about the infinite possibilities that are apparent in our galaxy alone not to mention all the other dimensions of space and time that exist throughout this infinite universal reality of which we are apart of forever and always either in a biological state or in a state of energy or something else but the fact is that we are still in our infancy as an intellectual species and have a long road ahead of us to learn and understand even a small percentage of the big picture and i for one am so excited and in awe of what the future holds for every dimensional reality involved. personally i think that if UFOs are a hyper advanced intelligence then Artificial intelligence is a good bet and if they have been studying us then it's no surprise that they are keeping as low a profile as possible and not saying hello as they see us still killing each other over petty ignorance and non acceptance and non understanding their probably scared with good reason

 

[Atlan0001]

Our cellular structure is a life within life, and such lower forms of life came first before building us (so to speak). Once upon a time there probably was a mud hole somewhere upon a new Earth with chemistry ready to spark life like a match ready to fire. Then, in that very, very, vulnerable mud hole, life sparked. And it promptly looked to spread itself to every other mud hole it possibly could reach. Practically instant evolution in having survival instinct. Since life is here in billions to trillions, maybe more, of variations from one cell up, including life within life (maybe even within that single celled creature) that in no way believes itself to be lower forms of life -- or is even aware that there are any forms of life existing higher than its own, I think it managed to survive quite well to spread and to evolve variation and complexity to even better survive and prosper. Now it has reached the ready point -- it has reached beginning point -- all over again. Deja-vu. History repeating so to speak. Does it expand out from this very, very, vulnerable planetary size "mud hole"? Or does it just turn inwardly to itself to await certain, inevitable, extinction, proving to life's nature that it is no real survivalist, no real prosperous, life at all?

Likely, if and when we reach out in expansion of life in massive amounts of life and energetic space based and faring structure, we won't realize that, then, we have achieved yet another evolution of life. We will be the life within the structure and infrastructure of a life that has become a life of its own. We will believe we are in control, well some will believe they are in control, and [that] life the next level up that we have been long energizing and sparking to emergence (to animation), will believe it is the aware and in control, when in fact the case will be a symbiosis between two levels of complex life forms that neither is aware of the other being aware. A few, a very few, in the lower level within may realize what has happened and throw up their hands saying, "Dammit! Our creation has taken on a life of its own!" Frontier-wise, it may not be a bad thing. No bad thing at all. Somewhere, probably many somewheres and times over, it may probably have already happened. That is, excluding our own mud hole world (our very local universe) and beginning billions of years ago, and us now on Earth at yet another threshold edge of (nova) beginning, of (nova) expansion to survive and prosper, or implode and go extinct (from implosion, if not from some other cause).

 

[Trevize62]

I've been reading through all the posts on this thread and there are some very interesting comments, factual statistics and points of view but i have noticed that we homo sapien sapiens as intelligent and advanced as we are at this moment are still very limited in our thinking and quite close minded about how we process our thoughts and if something doesn't make sense to us then it's either wrong, insane or is just far to mind boggling to comprehend so isn't worth pursuing with logical scientific thoughts and studies but we don't really know anything about the infinite possibilities that are apparent in our galaxy alone not to mention all the other dimensions of space and time that exist throughout this infinite universal reality of which we are apart of forever and always either in a biological state or in a state of energy or something else but the fact is that we are still in our infancy as an intellectual species and have a long road ahead of us to learn and understand even a small percentage of the big picture and i for one am so excited and in awe of what the future holds for every dimensional reality involved. personally i think that if UFOs are a hyper advanced intelligence then Artificial intelligence is a good bet and if they have been studying us then it's no surprise that they are keeping as low a profile as possible and not saying hello as they see us still killing each other over petty ignorance and non acceptance and non understanding their probably scared with good reason

Do not make bad science fiction, please