for National Geographic News
A recent study suggests that dust in interstellar space can arrange itself into structures that resemble inorganic life-forms.
According to a team of Russian scientists, lifelike behavior could occur in certain configurations of plasma—a state of matter composed of electrically charged atoms.
The claim has drawn mostly baffled, and skeptical, responses from physicists and alien-life experts.
Vast, diffuse clouds of dust and plasma are prevalent throughout the universe. (See a National Geographic magazine feature on "Dust in Space".)
Using computer simulations, a team led by Vadim Tsytovich, of Russia's General Physics Institute in Moscow, found that under certain conditions dust and plasma can organize into stable, helix-shaped structures resembling DNA.
While the structures exhibit none of the complex chemistry associated with even the simplest forms of life on Earth, they appear to at least mimic some the basic processes associated with living systems, the team said.
For example, the helical strands were sometimes capable of reproducing by splitting and reassembling into two identical copies.
The structures also exhibited a kind of evolution, according to the researchers.
Structural changes that took place in the strands were passed from one "generation" to the next, the researchers said. As conditions changed, only the most stable configurations were able to persist.
Because of these and other characteristics, Tsytovich's team argued that the dusty plasma structures should be considered a form of inorganic life.
"It appears from our numerical simulations that large assemblies of dusty plasmas may satisfy the commonly accepted minimum conditions used to define life," said co-author Gregor Morfill of the Max Planck Institute for Extraterrestrial Physics in Germany.
Morfill said that while the results were based on computer models, lifelike plasmas may one day be discovered in space.
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