"… "We are children of both the heavens and the Earth." (Carl Sagan)
Dec 30, 2010:? The first signs of life in a sticky ooze happen in science fiction films. But new research suggests instead started the action in the stormy sky above.
The idea came about from the research conducted by University of Arizona hear Sarah. Your team, transpirierenden in the lab, chemical reactions on the largest moon of Saturn, Titan.
"We are find, that the art can do an atmosphere of chemistry, has interesting implications for life on Earth and elsewhere in the solar system," says hear. "Titan's skies could do some interesting Chemistry: production of the building blocks of life."
Listen and a BREW of molecules (carbon monoxide(1), molecular nitrogen and methane) mixed their colleagues found in Titan's atmosphere. Then they zapped the preparation with radio waves proxy for the solar radiation.
Not the scientists "It's alive!" but it was screaming what as happened next do. Variety of complex molecules formed, including amino acids and nucleotides.
"Our experiment is the first evidence that the precursors of life can be up in an atmosphere without any liquid water(2)." This means building blocks of life could be in the air and then down from the sky rain! "
Titan is unique in our solar system. Dotted with lakes and dunes and atmosphere of nitrogen and methane, shrouded in a thick, it is a frozen time capsule of the early Earth. While the liquid on Titan's surface is methane instead of water, it is the only body in the solar system besides Earth with liquid on its surface.
"We begin not to prove that we 'life' in Titan's sky," explains hear. "We wanted to solve a mystery." "The probe Cassini detected large molecules(3) in Titan's atmosphere, and we wanted to find out what could be."
In the hope to get clues to the mystery molecules, hear computer codes used the lab results to match known molecular formulas search. She decided on a whim, look at nucleotides and amino acids.
"When I pressed enter, I expected a big 'no, not there.'"
She left for a break, and got a big surprise after his return.
"The computer was so long printing lists I thought, I must have made a mistake!"
But there was no error.
"We had about 5000 molecules, the the stuff: carbon, nitrogen, hydrogen and oxygen." We knew that we had the elements for organic molecules, but we could not say how they were arranged. It's kind of like Legos - the more there are, that can be made more possible structures. "And they can be in many ways along."
Among the structures identified in the lab so far five nucleotides in DNA and RNA and two amino acids are found experiment. But she says there could be more amino acids in the mix.
How could she generate Titan's atmosphere?
The answer lies in an other Cassini discovery: the plume water rays from Titan's sister moon of Enceladus. The researchers have good evidence that these geysers of the source of oxygen needs, needed to kick-off the first chain reactions for life.
"Water spout to the plume release calls, broken hydrogen and oxygen." "And oxygen atmosphere by just the amount outside is required, recognized in this atmosphere in titanium to the amount of carbon monoxide."
Then, other chemical reactions(4) occur, produce the heavier molecules, recognized the Cassini. If the lab results are correct, amino acids and nucleotides are in the mix.
"We still know not what are the actual molecules in Titan's atmosphere,", says hear, "but the way, the precursors of life on the surface of Titan rain are different."
Picture it: a moon spraying an another Moon with water to generate, the building blocks of life, which fall to the surface in a storm of the methane rain.
Real life may finally as science fiction, strange.
Author: Dauna Coulter | Editor: Dr. Tony Phillips | Credit: Science@NASA
Titan's haze can keep ingredients for life - the University of Arizona press release
End notes:
(1) Carbon monoxide in their simulation used the researchers because it is the most frequent occurring oxygen-containing molecule in Titan's atmosphere. The amount of oxygen in the early Earth's atmosphere, it is assumed that much as the amount in Titan's atmosphere but be in the form of carbon dioxide instead of carbon monoxide on Titan has been found. Later, life on Earth were much more oxygen in the Earth's atmosphere. Titan is still very little oxygen, especially when compared to the Earth. The rays of the sun UV break methane and molecular nitrogen in Titan's atmosphere, so that they recreate this process and in new types of molecules the molecules to recombine freely used radio waves.
(2) Conventional theories say amino acids and nucleotides, the building blocks and blueprints for life arose on Earth, had the large body of water. Previous researchers water in their simulations used to replicate the chemistry. It produces life elements in the laboratory by the addition of water, nitrogen and methane, which influenced known to early Earth's atmosphere. Horst's team left out, the "water and stir" step. (In all living things, amino acids form proteins that are the building blocks of life.) (Nucleotides are the DNA, resulting in the construction of these proteins.)
(3) Cassini discovered oxygen ions flow into the top of Titan's atmosphere. The probe was also heavy molecules, 100 times as large as methane, in the haze. But the Cassini instruments were not sensitive enough to identify them.
(4) The water is either broken by energetic particles to Saturn or by solar radiation. Then Saturn's magnetic field leads the hydrogen and oxygen from titanium, where they react with carbon monoxide, methane, solar radiation also until broken. Solar radiation breaks the nitrogen, methane, and carbon, sparking reactions that make up the heavier molecules, if, the Cassini detected.
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