Science has long since developed beyond the view that extra terrestrial life takes the form of little green men – but it could, say physicists, be made from corkscrew-shaped particles of interstellar dust.
|Scanning electron micrscope image of an interplanetary dust particle – new work shows that inorganic dust can organise and interact with each other.
Copyright, Don Brownlee, University of Washington, Seattle, and Elmar Jessberger, Institut für Planetologie, Münster, Germany.
An international team has discovered that under the right conditions, particles of inorganic dust can become organised into helical structures. These structures can then interact with each other in ways that are usually associated with organic compounds and life itself.
Leader of the team V.N. Tsytovich of the Russian Academy of Science, said: “These complex, self-organised plasma structures exhibit all the necessary properties to qualify them as candidates for inorganic living matter, they are autonomous, they reproduce and they evolve.”
Until now, physicists assumed that there could be little organisation in such a cloud of particles. However, Tsytovich and his colleagues demonstrated, using a computer model of molecular dynamics, that particles in a plasma can undergo self-organisation as electronic charges become separated and the plasma becomes polarised. This effect results in microscopic strands of solid particles that twist into corkscrew shapes, or helical structures.
Not only do these helical strands interact in a counterintuitive way in which like can attract like, but they also undergo changes that are normally associated with biological molecules, such as DNA and proteins, say the researchers. They can, for instance, divide, or bifurcate, to form two copies of the original structure.
These new structures can also interact to induce changes in their neighbours and they can even evolve into yet more structures as less stable ones break down, leaving behind only the fittest structures in the plasma.
The plasma conditions needed to form these helical structures are common in outer space. However, plasmas can also form under more down to earth conditions such as the point of a lightning strike. The researchers hint that perhaps an inorganic form of life emerged on the primordial earth, which then acted as the template for the more familiar organic molecules we know today.
The findings are published in the New Journal of Physics.