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.
What is your authority for that translation?
Huh? Since when did I say that lawful wrongdoings should be copied?
It says to allow them, do not dispute them, for they are the law.
In other words, it was un-Christian of myself to request that pic be taken off.
http://www.bibletexts.com/terms/genuine-christianity.htm#benevolence
and to answer the one above, of course that post. It was disgusting.
Why in the world did that idiot post 616 to me?
Apparently it is lawful to kill someone by withholding food and water. Is that your standard? Why does the verse start out with "Resist not evil"?
Perhaps it took him 17 posts to figure out how to post an image on here. (and spell)
Because you're Number One.
There was an image? Thankfully it didn't show up for me. Saved by the firewall perhaps.
Lawful and right are not the same. You should know that.
"39 But now I tell you: do not take revenge on someone who wrongs you. If anyone slaps you on the right cheek, let him slap your left cheek too"
Same source. See a pattern? It's in the translation. "Resist not evil" is the same as "thou shalt not kill"
It's "do not seek revenge on a wrongdoing" as it is "thou shalt no MURDER"
If you want, I'll send you the contents of the post, with a link to the image, by freepmail. Frankly, it's the worst image I've seen on the internet. The text was pretty bad too.
Yes, but the pic involved number two.
Who does Number 2 work for?
To be biologically correct, she should have done the dad's voice after his mate died.
Obviously blocked by the firewall I'm behind. Interesting that whoever chose a crevo thread. I wonder what that was about.
How about a belief that JESUS is God??
Matt 5:39 But I say unto you, That ye resist not evil: but whosoever shall smite thee on thy right cheek, turn to him the other also.
Luk 6:29 And unto him that smiteth thee on the [one] cheek offer also the other; and him that taketh away thy cloke forbid not [to take thy] coat also.
Matt 5:40 And if any man will sue thee at the law, and take away thy coat, let him have [thy] cloak also.
(I see no ROBBERY here.)
Luk 18:22 Now when Jesus heard these things, he said unto him, Yet lackest thou one thing: sell all that thou hast, and distribute unto the poor, and thou shalt have treasure in heaven: and come, follow me.
(Jesus was speaking to a specific individual here; not to all of 'Christianity'.)
(I don't see these as fitting your original statement....)
Matt 5:41 And whosoever shall compel thee to go a mile, go with him twain. (No robber here)
Luk 6:30 Give to every man that asketh of thee; and of him that taketh away thy goods ask [them] not again. (nothing about giving away everything here)
Luk 18:25 For it is easier for a camel to go through a needle's eye, than for a rich man to enter into the kingdom of God. (Yup, we love our STUFF more than God.)
Why not?
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