The Earliest Time of Life in Universe

[Dmitry67]

What is he earliest time when life could form in the Universe? If it is infinite, there always are very ‘lucky’ regions.

We need population III stars, with a very short lifespan. They explode and form clouds with higher metallicity (I assume it is not enough for solid planets?). So we have generation 2 stars. Make it as heavy as possible to accelerate a process. Finally we get generation 3 star with solid planets. 2 previous generations are very heavy so it won’t take more than 30-50My if I am lucky. This time is irrelevant in comparison with a time for the planet to cool down?

So the answer is: Time of first stars + min 500-600My?

 

[Mihael@@/&]

My guess is that 500-600MY could be enough, because after 400MY after BB there were first galaxies.

 

[Tanelorn]

This seems to early to me. Perhaps I am thinking intelligent life.

1. Another quesion that is very interesting, at least to me, is what would the first intelligent observers of the universe be able to see that we see can't today?

2. Also what is the maximum level of development of intelligent life that is possible in 13G years and also in an unlimited time?

Surely two excelent reasons for making contact by SETI despite Hawking's recent views about the possible dangers.

The fact that we are not making contact already is a little odd really in the light of the possible answers from the second quesion. I suppose it is a very large universe!

 

[Chalnoth]

My guess is that 500-600MY could be enough, because after 400MY after BB there were first galaxies.

You don't just need stars, though, but second or third-generation stars (because you need heavier elements than hydrogen and helium to form life). So you need time for lots of supernovae to go off, for the material from those supernovae to spread out and form other star systems, and then for the local region to become quiet so that new supernovae don't kill off any life that does get started. I'm not sure exactly how much time that would take.

 

[Mihael@@/&]

I didn't get that topic is about inteligent life.
(Third-generation stars, try to find any info when those formed : )

 

[PhilKravitz]

To make Earth like life you need Earth like conditions. I am guessing life can evolve in many conditions.

For molecular bases things we need temperatures low enough that the molecular persist. By 16 million year the universal temperature is down to 275 degree kelvin from Cosmology by Weinberg.

An important question is how long does it typically take for life to evolve once conditions are suitable?

 

[Chalnoth]

An important question is how long does it typically take for life to evolve once conditions are suitable?

We don't know yet, but life appears to have evolved on Earth within a couple hundred million years from the time it cooled enough for life to be possible.

 

[PhilKravitz]

We don't know yet, but life appears to have evolved on Earth within a couple hundred million years from the time it cooled enough for life to be possible.

Of course there is some probability of seeding from off world. In which case it may have taken a long time (something <10 billion years). I am not a fan of off world seeding but just had to mention it.

 

[Chalnoth]

Of course there is some probability of seeding from off world. In which case it may have taken a long time (something <10 billion years). I am not a fan of off world seeding but just had to mention it.

There's no possibility of seeding from outside the solar system, so no, it couldn't take anywhere near that long. Seeding from elsewhere in the solar system, though unlikely, would only extend the potential required time by a factor of two or so at most.

Even then, the fact remains that a sample size of one simply isn't large enough to make any significant conclusions about how rapidly life forms.

 

[Tanelorn]

I sometimes wonder if the whole galaxy is full of organic matter left over from other earlier solar systems that have long since been destroyed and which has survived deep inside icy comets which eventually reached Earth to help fill our oceans.

However one thing is for sure, life did start somewhere, somehow.

 

[lowing99]

There's no possibility of seeding from outside the solar system, so no, it couldn't take anywhere near that long. Seeding from elsewhere in the solar system, though unlikely, would only extend the potential required time by a factor of two or so at most.

Hi Chalnoth, there does seem to be a body of opinion that proposes viral life in comets, It's been a while since I read up on this but I think the proposal was that viruses are still being deposited each time we pass through a comet tail however dispersed they may be.

Slight tangent apologies

Best
Colin

 

[Chalnoth]

Hi Chalnoth, there does seem to be a body of opinion that proposes viral life in comets,

Comets do not come from other solar systems. They are very much part of our own solar system.

 

[lowing99]

Comets do not come from other solar systems. They are very much part of our own solar system.

Sorry, Was referring to the seeding from within the solar system, I don't know if comets pre date the Earth's formation.

 

[Chalnoth]

Sorry, Was referring to the seeding from within the solar system, I don't know if comets pre date the Earth's formation.

The entire solar system (including the comets) formed at roughly the same time.

 

[Chronos]

Assuming 4.5 billion years is roughly average under ideal circumstances, it appears very unlikely intelligent life could have evolved earlier than 5-6 billion years after the big bang. Given energetic events like gamma ray bursters were fairly common in the early universe, 10 billion years looks like a more reasonable guess. This suggests a significant probability we are among the 'youngest' intelligent beings to have evolved in the universe.

 

[Dmitry67]

But the very first 2-3 billion years were wasted, there was almost no progress. So on lucky planet the whole evolution from the very first life to intelligent species can be compressed into 500-600my.

 

[thorium1010]

But the very first 2-3 billion years were wasted, there was almost no progress. So on lucky planet the whole evolution from the very first life to intelligent species can be compressed into 500-600my.

what about the great oxygenation event, which happened around 2. 3 or 2.4 billion years ago or the evolution of prokaryotes prior to the oxygenation event.
oxygen was absent in the primitive or early Earth atmosphere. once cyanobacteria or other photosynthetic evolved, the atmosphere changed giving rise to 21% oxygen today. so evolution of photosynthesis was fundamental for the rise of other organisms including mammals.

 

[Chronos]

It appears life on Earth originated from undersea volcanic vents, so, I don't perceive your point as valid, Dmitry67.

 

[Dmitry67]

thorium2010 - oxygen was created by life, so what the point?
Chronos - I did not know. But on lucky planet volcanic activity can be also... very lucky...
And in truly infinite universe there is the most lucky planet... actually, an infinite number of the most lucky planets, giving an *exact* answer to my question.

This is the point - the answer is not 'something about X My'. An answer is exact, even we can only think about some limits...

 

[Chalnoth]

It appears life on Earth originated from undersea volcanic vents,

As near as I can tell, a lot of this is still very much up in the air. There are reasons to believe life originated there, but as near as I can tell the most evidence we have of it so far is that the chemistry seems plausible so far. That's not terribly good evidence.

 

[thorium1010]

Dimitry67 - you posted that -In the first 2 to 3 billion years of earth, life did not progress, rather it was a waste of time.

The explosion of life in later part of Earth history could only occur in the presence of oxygen. First Earth atmosphere had to be oxygenated also methane and carbon dioxide had to be removed or trapped by photosynthesis which in my opinion is a major event.

 

[Dmitry67]

thorium1010, I partly agree.

The 'jump' to the very first life which was able to produce an oxygen could be very fast;
however, you're right, it took time to *accumulate* enough oxygen in the atmosphere.

 

[Chalnoth]

thorium1010, I partly agree.

The 'jump' to the very first life which was able to produce an oxygen could be very fast;
however, you're right, it took time to *accumulate* enough oxygen in the atmosphere.

The amount of time required to accumulate the oxygen was pretty much inconsequential. The essential component was indeed photosynthesis.

However, it is by no means clear whether or not the time required for Earth-borne organisms to evolve this capacity was long (or short, for that matter). The basic issue here is that modern single-celled organisms are frightfully complex organisms. And before the advent of oxygen, due to the lack of energy before photosynthesis, it may simply have taken a very long time to build up all of the machinery required to get photosynthesis off the ground.

I think it's a bit naive to simply assume that the evolution before multi-cellular life came about was mostly worthless.

 

[thorium1010]

However, it is by no means clear whether or not the time required for Earth-borne organisms to evolve this capacity was long (or short, for that matter). The basic issue here is that modern single-celled organisms are frightfully complex organisms. And before the advent of oxygen, due to the lack of energy before photosynthesis, it may simply have taken a very long time to build up all of the machinery required to get photosynthesis off the ground.

I think it's a bit naive to simply assume that the evolution before multi-cellular life came about was mostly worthless.

The study how initial life forms were formed or evolved before oxygen (free oxygen)was present in the atmosphere, would probably give us clues about finding life on other planets. Life would have struggled in the hostile condition that existed during early part of Earth history.

 

[Tanelorn]

Hi Chalnoth, I refer to your message on the previous page that comets originated only in our solar system.

During a supernova wouldn't a large amount of matter of many different elements be sent out into space all directions at very high velocities? Can some of this matter be solid matter and larger than individual atoms? Can these objects accumulate frozen water over time? Would these objects disperse everywhere eventually forming a parts of new solar systems? I recall someone saying we were all made from star dust made inside an ancient supernova out there somewhere?

 

[Chalnoth]

Hi Chalnoth, I refer to your message on the previous page that comets originated only in our solar system.

During a supernova wouldn't a large amount of matter of many different elements be sent out into space all directions at very high velocities? Can some of this matter be solid matter and larger than individual atoms? Can these objects accumulate frozen water over time? Would these objects disperse everywhere eventually forming a parts of new solar systems? I recall someone saying we were all made from star dust made inside an ancient supernova out there somewhere?

The matter is really too diffuse until it falls into something like a solar system. Yes, we all come from the explosions of supernovae, but the matter that is blown out from them is a very diffuse gas, until it recollapses into new solar systems.

 

[epenguin]

When I last followed this (and went to a few conferences) nearly all were agreed life formed very early on Earth when conditions allowed it. And of course in all things on origins you are more likely to under-estimate than over-estimate the antiquity of anything. And viewed from this end if we know it to an uncertainty of 10% we are doing well. But viewed from the other end, the start, the difference between 4 and 4.5 billion years is the difference between say 1,000 years and half a billion years from start! But at any rate life seems to have been around for most of the Earth's history. It, I mean our ancestors, could of course have been around for more than that if it came from Mars which used to have more exchanges with us than now, but we still get about a ton a year from there, a possibility that seemed not so very dismissible according to these discussions.

Now about life elsewhere, according to one presentation - oh first someone needs to explain what astronomers mean by 'metals' - it is not the same as what everybody else means. Anyways this astronomer was talking about the abundance of metals in the various types of stars and also looking to what the universe has produced and when and what it can do in the future. Since these elements are essential in life, the upshot was that life is a party we have arrived at when it is nearly over!

Unfortunately I have not followed this stuff for more than ten years - I might still be able to find more, but maybe there are experts here.

 

[Tanelorn]

Chalnoth, looks like my hypothesis of comets from other solar systems is believed possible by others:


In 1950, the idea was independently revived by Dutch astronomer Jan Hendrik Oort as a means to resolve a paradox:[7] over the course of the Solar System's existence, the orbits of comets are unstable; eventually, dynamics dictate that a comet must either collide with the Sun or a planet, or else be ejected from the Solar System by planetary perturbations.


"In June 2010 Harold F. Levison and others have suggested on the basis of enhanced computer simulations that the Sun "captured comets from other stars while it was in its birth cluster." Their results imply that "a substantial fraction of the Oort cloud comets, perhaps exceeding 90%, are from the protoplanetary disks of other stars." [28]"


http://en.wikipedia.org/wiki/Oort_cloud

 

[Deuterium2H]

Getting back to the original topic, as to how early organic life could have arisen in the Universe...

It is not simply the need for the development of Population 1/1.5 stars, but also the relative concentrations of heavier elements withing stellar nurseries. Many generations of stars would have to occur before there would be sufficient abundance of elements such as carbon, iron, nitrogen, oxygen, etc., distributed across the proper gradients. If the chemical abundance is too diffuse, then there may not exist the necessary concentrations of organics to start and sustain the complex chain of reactions required for life, as we know it.

The oldest Population 1 stars are approximately 6-9 billion years old. It is still a matter of debate as to if stellar systems belonging to young, Population 2 stars (let's call them Population 1.5, for sake of argument) may be sufficiently rich in metals as to support life. Again, for the sake of argument let's assume that some Population 1.5 systems were suitable. These stars are 8-10 billion years old. So, in our 13.7 billion year old Universe, it is possible that the earliest conditions suitable for life did not arise until the Universe was at least approx. 4 billion years old...and more probably 5-7 billion years old.

Notice that this time frame affords the possibility that there exists not only life, but complex, intelligent, technological civilizations that could be billions of years older then our own.

 

[Dmitry67]

But is it possible to 'jump' to metal-rich stars assuming that their progenitors were very heavy -> with very short lifespan?

Say,
* H (with some He) - gas from Big Bang
* Very heavy star -> booooom, hypernova explosion in <1My
* Condensation -> few My
* Wolf–Rayet -> booom, 'ordinary' supernova in <1My

We can have several generation in 10-20My!