Space dust in plasma organizes into double helix shape—like DNA

William Atkins
Tuesday, 21 August 2007 20:05

Science - Space

Researchers used computer modeling to show that microscopic inorganic interstellar dust (space dust) injected into plasma will organize into single and double-helixes, the shape of DNA, with properties that look similar to living organisms.

An international team of researchers, from Russia, Germany, and Australia, suggest from their study that when electrically charged interstellar dust particles (those in plasma, the fourth state of matter) are in a microgravity environment of space (commonly called zero gravity) they are attracted to each other. Thus, they join together in a string-like configuration and then twist themselves into spiral (corkscrew-like) shapes.

DNA is deoxyribonucleic acid, the substance that carries an organism's genetic information. Plasma is the fourth state of matter (the other three being gas, liquid, solid), which is ionized gas, such as what is found in stars.

The shape was held together by electromagnetic forces. It appeared to the scientists that the group of dust particles could reproduce, transferring the information acquired as to its helix shape into the next generation.

The researchers suggest that the final shape allows the dust to better adapt to and survive in their environment. Team member V. N. Tsytovich, of the Russian Academy of Science, states in the Space.com article “Hot Gas in Space Mimics Life,” “These complex, self-organized plasma structures exhibit all the necessary properties to quality them as candidates for inorganic living matter.”

However, Gregor Morfill, another team member, from the Max Planck Institute for Extraterrestrial Physics, states in the same article, “I would hesitate to call it life. The reason why we published this paper is not because we wanted to suggest this could evolve into life, but because we wanted to start the discussion … once more of what exactly do we mean by life.”

The team’s article (“From plasma crystals and helical structures towards inorganic living matter”) is published in the August 14, 2007 issue of the New Journal of Physics.

Their abstract includes the following (with sentences bolded for emphasis) :

“Complex plasmas may naturally self-organize themselves into stable interacting helical structures that exhibit features normally attributed to organic living matter. The self-organization is based on non-trivial physical mechanisms of plasma interactions involving over-screening of plasma polarization. As a result, each helical string composed of solid microparticles is topologically and dynamically controlled by plasma fluxes leading to particle charging and over-screening, the latter providing attraction even among helical strings of the same charge sign. These interacting complex structures exhibit thermodynamic and evolutionary features thought to be peculiar only to living matter such as bifurcations that serve as `memory marks', self-duplication, metabolic rates in a thermodynamically open system, and non-Hamiltonian dynamics. We examine the salient features of this new complex `state of soft matter' in light of the autonomy, evolution, progenity and autopoiesis principles used to define life. It is concluded that complex self-organized plasma structures exhibit all the necessary properties to qualify them as candidates for inorganic living matter that may exist in space provided certain conditions allow them to evolve naturally.”

The researchers involved with the study include: V. N. Tsytovich and N.G. Gusein-Zade, from the General Physics Institute, Russian Academy of Science; G. E. Morfill and B. A. Klumov, from the Max Planck Institute for Extraterrestrial Physics (Germany); V. E. Fortov, from the Institute of Physics of Extreme State of Matter, Russian Academy of Science; and S. V. Vladimirov, from the School of Physics, The University of Sydney (Australia).