Top Stories - Posted by Steve Koppes-Chicago on Monday, April 2, 2012 10:31 - 1 Comment 
(No Ratings Yet)
Loading ...
(No Ratings Yet) Loading ...Solar nebula kicks off organic compounds
New computer simulations at the University of Chicago show that turbulence lofts dust particles above the illuminated portion of the cloud where they become exposed to high levels of ultraviolet light from nearby stars. UV irradiation was a key component in the production of complex organic molecules in the early solar system. (Credit: NASA/JPL-Caltech)
U. CHICAGO (US) — Researchers say complex organic compounds—many important to life on Earth—were readily produced in the primordial solar system.
Share this article
Email
Republish this article
The text of this article by Futurity is licensed under a Creative Commons Attribution-No Derivatives License.
Scientists at the University of Chicago and NASA Ames Research Center came to this conclusion after linking computer simulations to laboratory experiments.
Fred Ciesla, assistant professor in geophysical sciences, simulated the dynamics of the solar nebula, the cloud of gas and dust from which the sun and the planets formed.
Although every dust particle within the nebula behaved differently, they all experienced the conditions needed for organics to form over a simulated million-year period.
“Whenever you make a new planetary system, these kinds of things should go on,” says Scott Sandford, a space science researcher at NASA Ames. “This potential to make organics and then dump them on the surfaces of any planet you make is probably a universal process.”
Although organic compounds are commonly found in meteorites and cometary samples, their origins presented a mystery. Now Ciesla and Sandford describe how the compounds possibly evolved in the March 29 edition of Science Express. How important a role these compounds may have played in giving rise to the origin of life remains poorly understood, however.
Sandford has devoted many years of laboratory research to the chemical processes that occur when high-energy ultraviolet radiation bombards simple ices like those seen in space. “We’ve found that a surprisingly rich mixture of organics is made,” Sandford says.
These include molecules of biological interest, including amino acids, nucleobases, and amphiphiles, which make up the building blocks of proteins, RNA, and DNA, and cellular membranes, respectively. Irradiated ices should have produced these same sorts of molecules during the formation of the Solar System, he says.
But a question remained: Could icy grains traveling through the outer edges of the solar nebula, in temperatures as low as minus-405 degrees Fahrenheit (less than 30 Kelvin), become exposed to UV radiation from surrounding stars?
Ciesla’s computer simulations reproduced the turbulent environment expected in the protoplanetary disk. This washing machine action mixed the particles throughout the nebula, and sometimes lofted them to high altitudes within the cloud, where they could become irradiated.
“Taking what we think we know about the dynamics of the outer solar nebula, it’s really hard for these ice particles not to spend at least part of their time where they’re going to be exposed to UV radiation,” Ciesla says.
The grains also moved in and out of warmer regions in the nebula. This completes the recipe for making organic compounds: ice, irradiation, and warming.
“It was surprising how all these things just naturally fell out of the model,” Ciesla says. “It really did seem like this was a natural consequence of particle dynamics in the initial stage of planet formation.”
More news from the University of Chicago: http://news.uchicago.edu/
Please wait
This is the same theory about how basic molecules mix and tumble with the tide to make life. Life forms this way just the same as it forms toast in the toaster through a random action of the early universe. Millions if not Billions of people will grab on to this new faith based idea of the origin of life. Anything but an obvious answer that has already been around. Because it is new it must be true. Sorry I need a little more evidence.