Hi Billy T!
This post {14 by Billy T} describes problems life has to face to survive in space as we consceive it today.
But space today is very different from the solar system as it was in the beginning.
Yes in the early universe space was smaller and hotter - so hot intitially that no matter existed - certainly no life even after the first very large stars formed (typically 100 times more massive than the sun with very much more intense UV that would destroy any life that came into the universe.)
I don´t think life could even survive when space was hotter than boiling water and harsh UV rich.
Here Im talking "stellar clouds" and you travel all they way back to the big bang! No harm in that I suppose, we really should try to estimate the earliest possibility for life as we know it for to originate.We know that at least one stellar cloud produced life somewhere in its ordinary business of producing a solar system, and all im saying is that we as of yet do not know exactly how and where it was done.
But we know what the building blocks are and the earliest stellar clouds did not contain all of them. When the stellar clouds got enriched by elements produced in stars, there were clouds having all necessary atoms. But there you seem to claim that radiation was too high for life to form! You might be right...who knows? But there is life able to resist high doses of radiation:
http://en.wikipedia.org/wiki/Micrococcus_radiodurans
Next you seem to discuss a small hot universe "hotter than boiling water"! Are you sure that the stellar cloud that became our solar system began in that condition? Mind you, I am discussing "Stellar Clouds" in general and are you seriously claiming that stellar clouds are hotter than boiling water? This means water would only exists as a gas... I hear that comets are ice... isnt something wrong in your picture of stellar clouds?
There is life that can resist high temperatures:
http://en.wikipedia.org/wiki/Thermophile
There was less radiation and matter had not yet condensed into sun and planets... Your argument seems limited to modern space... not intended to cover all the changes the stellar system goes through from beginning to end.
That is correct, yes I do assume matter is required for life to exist and once it does for the intensity of UV filling the smaller universe to decrease before life could even survive, much less arise from hot non-living matter.
Your text I made bold is in error: There was much more and much more intense UV radiation back then, (even gamma rays!) not less.
Do you have some point with this post of yours? Or is it just pure ignorant nonsense?
Im not sure what this "ignorant nonsense" refers to...
It seems to me you think I believe lifes origin is close to the Big bang and I cant understand what makes you think so...
Please explain what you mean. Meanwhile heres some more "ignorant nonsense" from elsewhere
I. Contraction of insterstellar cloud
Solar system formed about 4.6 billion year ago, when gravity pulled together low-density cloud of interstellar gas and dust
Initially the cloud was about several light years across. A small overdensity in the cloud caused the contraction to begin and the overdensity to grow, thus producing a faster contraction --> run away or collapse process
Initially, most of the motions of the cloud particles were random, yet the nebula had a net rotation. As collapse proceeded, the rotation speed of the cloud was gradually increasing due to conservation of angular momentum.
Gravitational collapse was much more efficient along the spin axis, so the rotating ball collapsed into thin disk with a diameter of 200 AU (0.003 light years) (twice Pluto's orbit), aka solar nebula (movie), with most of the mass concentrated near the center.
As the cloud contracted, its gravitational potential energy was converted into kinetic energy of the individual gas particles. Collisions between particles converted this energy into heat (random motions). The solar nebula became hottest near the center where much of the mass was collected to form the protosun(the cloud of gas that became Sun).
At some point the central temperature rose to 10 million K. The collisions among the atoms were so violent that nuclear reactions began, at which point the Sun was born as a star, containing 99.8% of the total mass.
What prevented further collapse? As the temperature and density increased toward the center, so did the pressure causing a net force pointing outward. The Sun reached a a balance between the gravitational force and the internal pressure, aka as hydrostatic equilibrium, after 50 million years.
Around the Sun a thin disk gives birth to the planets, moons, asteroids and comets. Over recent years we have gathered evidence in support of this theory.
The disk contained only 0.2% of the mass of the solar nebula with particles moving in circular orbits. The rotation of the disk prevented further collapse of the disk.
Uniform composition: 75% of the mass in the form of hydrogen, 25% as helium, and all other elements comprising only 2% of the total.
The material reached several thousand degrees near the center due to the release of gravitational energy --> it was vaporized. Farther out the material was primarily gaseous because H and He remain gaseous even at very low T. The disk was so spread out that gravity was not strong enough to pull material and form planets.
As the disk radiated away its internal heat in the form of infrared radiation (Wien's law) the temperature dropped and the heaviest molecules began to form tiny solid or liquid droplets, a process called condensation.
There is a clear relation between the temperature and the mass of the particles that become solid (Why?). Near the Sun, where the T was higher, only the heaviest compounds condensed forming heavy solid grains, including compunds of aluminum, titanium, iron, nickel, and, at somewhat cooler temperatures, the silicates.
In the outskirts of the disk the T was low enough that hydrogen-rich molecules condensed into lighter ices, including water ice, frozen methane, and frozen ammonia.
The ingredients of the solar system fell into four categories:
Metals: iron, nickel, aluminum. They condense at T~1,600 K and comprise only 0.2% of the disk.
Rocks: silicon-based minerals that condense at T=500-1,300 K (0.4% of the nebula).
Ices: hydrogen compounds like methane (CH4), ammonia (NH3), water (H2O) that condense at T~150 K and make up 1.4% of the mass.
Light gases: hydrogen and helium that never condensed in the disk (98% of the disk).
The great temperature differences between the hot inner regions and the cool outer regions of the disk determined what of condensates were available for life formation at each location from the center. The inner nebula was rich in heavy solid grains and deficient in ices and gases. The outskirts are rich in ice, H, and He. I changed one word in the quote to make my point... its red!
Meanwhile heres a quote from wikipedia, and here I also change it a little, the words in blue are mine:
Origin of the first cell
There are several theories about
the origin of small molecules that could lead to life in the solar system. One is that they came from meteorites (see Murchison meteorite). Another is that they were created at deep-sea vents. A third is that they were synthesized by lightning in a reducing atmosphere (see Miller–Urey experiment); although it is not clear if Earth had such an atmosphere.
There are essentially no experimental data defining what the first self-replicating forms were.
Scientists are divided over the likelihood of life arising independently
on Mars, or
on other planets in our galaxy.
Im just a poor lonesome philosopher checking the foundations of our knowledge, and it has struck me as peculiar that scientists and forum geniouses are so certain that lifes origin was on a planet! How do they KNOW that the immediately preceeding period before planet Earth was formed had nothing to do with the formation of life? Have they considered the conditions in the condensate later to be earth? Wasnt there zillions of droplets of water containing amino acids and other higher building blocks of life? Being stirred by radiation? Were the processes of selforganisation and self cata... Well you know what I mean dont you?
