Stanley Miller's classic "primordial soup" experimental setup,
with a simulated ocean, lightning and broth
of hydrogen, methane, ammonia and water.
Posted on 04/08/2005 7:39:14 AM PDT by PatrickHenry
A new University of Colorado at Boulder study indicates Earth in its infancy probably had substantial quantities of hydrogen in its atmosphere, a surprising finding that may alter the way many scientists think about how life began on the planet.
Published in the April 7 issue of Science Express, the online edition of Science Magazine, the study concludes traditional models estimating hydrogen escape from Earth's atmosphere several billions of years ago are flawed. The new study indicates up to 40 percent of the early atmosphere was hydrogen, implying a more favorable climate for the production of pre-biotic organic compounds like amino acids, and ultimately, life.
The paper was authored by doctoral student Feng Tian, Professor Owen Toon and Research Associate Alexander Pavlov of CU-Boulder's Laboratory for Atmospheric and Space Physics with Hans De Sterk of the University of Waterloo. The study was supported by the NASA Institute of Astrobiology and NASA's Exobiology Program.
"I didn't expect this result when we began the study," said Tian, a doctoral student in CU-Boulder's Astrobiology Center at LASP and chief author of the paper. "If Earth's atmosphere was hydrogen-rich as we have shown, organic compounds could easily have been produced."
Scientists believe Earth was formed about 4.6 billion years ago, and geologic evidence indicates life may have begun on Earth roughly a billion years later.
"This study indicates that the carbon dioxide-rich, hydrogen-poor Mars and Venus-like model of Earth's early atmosphere that scientists have been working with for the last 25 years is incorrect," said Toon. In such atmospheres, organic molecules are not produced by photochemical reactions or electrical discharges.
Toon said the premise that early Earth had a CO2-dominated atmosphere long after its formation has caused many scientists to look for clues to the origin of life in hydrothermal vents in the sea, fresh-water hot springs or those delivered to Earth from space via meteorites or dust.
The team concluded that even if the atmospheric CO2 concentrations were large, the hydrogen concentrations would have been larger. "In that case, the production of organic compounds with the help of electrical discharge or photochemical reactions may have been efficient," said Toon.
Amino acids that likely formed from organic materials in the hydrogen-rich environment may have accumulated in the oceans or in bays, lakes and swamps, enhancing potential birthplaces for life, the team reported.
The new study indicates the escape of hydrogen from Earth's early atmosphere was probably two orders of magnitude slower than scientists previously believed, said Tian. The lower escape rate is based in part on the new estimates for past temperatures in the highest reaches of Earth's atmosphere some 5,000 miles in altitude where it meets the space environment.
While previous calculations assumed Earth's temperature at the top of the atmosphere to be well over 1,500 degrees F several billion years ago, the new mathematical models show temperatures would have been twice as cool back then. The new calculations involve supersonic flows of gas escaping from Earth's upper atmosphere as a planetary wind, according to the study.
"There seems to have been a blind assumption for years that atmospheric hydrogen was escaping from Earth three or four billion years ago as efficiently as it is today," said Pavlov. "We show the escape was limited considerably back then by low temperatures in the upper atmosphere and the supply of energy from the sun."
Despite somewhat higher ultraviolet radiation levels from the sun in Earth's infancy, the escape rate of hydrogen would have remained low, Tian said. The escaping hydrogen would have been balanced by hydrogen being vented by Earth's volcanoes several billion years ago, making it a major component of the atmosphere.
In 1953, University of Chicago graduate student Stanley Miller sent an electrical current through a chamber containing methane, ammonia, hydrogen and water, yielding amino acids, considered to be the building blocks of life. "I think this study makes the experiments by Miller and others relevant again," Toon said. "In this new scenario, organics can be produced efficiently in the early atmosphere, leading us back to the organic-rich soup-in-the-ocean concept."
In the new CU-Boulder scenario, it is a hydrogen and CO2-dominated atmosphere that leads to the production of organic molecules, not the methane and ammonia atmosphere used in Miller's experiment, Toon said.
Tian and other team members said the research effort will continue. The duration of the hydrogen-rich atmosphere on early Earth still is unknown, they said.
Of course, MacDorcha's idea was to speed up the processes of life that took say a billion years to happen naturally so much that they would take a relatively short amount of time so we can study them. This would involve an increase of atomic speeds by a factor of say a million, in which case the process would still take a thousand years. However, if you increase the ambient temperature from a typical lab temperature of 300K by a factor of a million, you would have a temperature of 300000000K! If I remember my basic physics, atoms certainly couldn't exist at this high of a temperature let alone organic compounds.
"However, what I really meant was that you cannot accelerate the process to any desired degree; there will always be an upper temperature limit beyond which any potential life would be destroyed."
Of course. This is even obvious in Health class. We need heat to metabolize, but that same heat causes radicals that kill us slowly (hence, we MUST die!)
But accelerated metabolism not-withstanding, the building blocks do not "die" when they are heated. Organic compounds are what I refer to. These are built faster (and form amino acids faster) when heated. This would speed up the process by several factors.
I'll post more later, my roommates are blaring music right now. I'm going to find a better place.
See my post #241. I meant to ping you to this post and forgot.
"dirt only came into existence after life.. and death. "
So, the T-shirt my son gave to me that says "Older Than Dirt" means that I am prebiotic.
So....., let's see. If I am prebiotic and I have invented sex, at least a few times, and I have created sons (life), then I must be the Creator.
Wow! who would have thought :^)
The only reason I ignore Madame Heisenberg's advice is because she's wrong 50% of the time.
This is a just-so argument. If you actually look at the organic molecules involved, you'll find an interesting catch-22. The molecules are required for life, yet can only be constructed by living organisms.
It's the damning pronouncement of Chemistry (a true experimental science) that makes evolutionists back up hurriedly as they throw up their hands and say loudly: Our theory does NOT explain the origins of life.
Much of the chirality problem can be explained stochastically®. If the chirality of the "offspring" (biological, crystal, etc.) is the same as that of the parents, luck will select one type only.
Computer Experiment (I've actually run this several times):
I. Start with some population (balanced, unbalanced, I used 100 right and 100 left handed entities.)
II. Allow each entity to reproduce (deterministically is easy, I just doubled the number of each.)
III. For each entity, kill with some probablity (I used 1/2 to correspond with II.)
IV. If both species present, go to II.
This runs fast, (no storage.) It's the same mathematically as matching pennies; whoever is ahead stays ahead, ties are rare.
Of course human nature being what it is, I strongly suspect that most scientists would shy away from any experiment that would require 1000 years to produce results. We all want to know now, not do the dirty work so that some future generation can find out. Personally, I think that's probably also why, if there are alien civilizations, that we haven't heard a message from them. If we broadcast a message into space and wait for a reply, we have to wait for the message to get to its recipient and then for their reply to reach us. This would take, depending on the location of the aliens, hundreds, thousands, or even millions of years. However, if we just scan the sky listening for messages (ala the SETI project), if there is one, we would know NOW. Maybe that's what all the other civilizations are thinking also.
Psychic =
Psy = whay one does when a fool gives you almost free money for lying to them
chic = what you want to do to anyone's backside that actually BELIEVES this stuff!
I myself like my Primorital Soup with lots of compound crackers
The Dawkins program to produce the string "Methinks it is like a weasel" involves three processes: 1. Random variation -- on each "generation", 1/8th of the character strings in the "population" (size selected by user) have one of their text characters completely randomized to some other character. 2. Selection -- the character string which has the most "correct" characters (or if more than one such string exists, the most recent such) is flagged, and a) will be "bred", and b) won't itself be mutated or replaced by one of its own "offspring". 3. Reproduction -- the current "most fit" character string undergoes "sexual reproduction' with randomly chosen other strings, and the resulting offspring replace the "mates". (This is actually more akin to biological lateral gene transfer.) So all three of the processes necessary for evolution to take place are in the Dawkins program. And, as predicted by "evolutionists", the results are swift and sure -- the mutating, reproducing, subject-to-selection population very quickly (within seconds) produces a Shakespeare text string which the creationist "pure random" methods would not have produced before the Earth permanently froze over. |
It took nature nearly a half billion years to come up with the first primitive organism on this planet and yet you expect science to do it overnight.
I thought that FedEx Express did that............
"Uh uh. If one science is suppose to be legit, why not all the others? According to Quantum scientists, the universe had to be created by a thought, a word, or some kind of conciseness."
Hee. I wasn't questioning the validity of quantum physics. However, I thought the idea of quantum psychics per your typo, was funny.
I'd love to respond but I have a rule- any thread that goes over 200 posts has "jumped the shark".
Do you realize the true significance of this article is that one of the icons of evolution- the Miller experiment- has been completely discredited?
The term "Chaos" has been used somewhat differently for about the last 25 years in mathematics. Chaotic actions in dynamic systems are different from random actions. The Kolmogorov-Sinai entropy of a random system is infinite but it is finite for a chaotic system. (A "completely deterministic" system has zero Kolmogorov-Sinai entropy.) Of course, from observation, it's a bit hard to tell "a really big number" from "infinite."
One way to look at the classification is to notice that random systems cannot be predicted even if one knows the initial conditions. Determinist paths can be predicted even if one does not know the initial conditions. Chaotic systems would be deterministic but one isn't able to get the initial conditions. It's a bit of a change in usage; some people still lump chaotic and deterministic systems together.
No, it simply means that matter has a consistent set of properties and the regularities (which have unfortunately been called "laws") are a consequence of these properties.
Saying that there is "a law that they must obey" implies that these particles would rather do something else if no one's watching.
I guess my question would be "WHY do atoms behave according to their status?"
That's because of their particular properties.
Once again, there is no certain way atoms or any other particles should behave, they simply do.
A better question would be "WHY should atoms (or other particles) behave any differently in the absence of intermeddling forces (e.g. djinns, gods, gremlins, etc.)?"
"Soil" (sort of by definition) requires some type of broken rock (sand, clay), organic matter (dead leaves, rats), air, and water. Lacking any of these, edaphologists (or soil scientists as dirt doctors are now called), don't call it soil.
That's right. And there is no gas lower in weight than hydrogen.
People do grow cultures in petri dishes at higher temperatures. Molds, fungi, and bacteria to reproduce somewhat faster. Your idea will work but not at too high a temperature. At higher temperatures, there are new chemical reactions not available at lower temperatures; not all of these are good for living things.
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