Search for origin of life reaches interstellar dust

Interstellar dust particles - not, you might imagine, the dampest places in the universe - but most of the water in the universe is in the form of very cold ice films deposited around these particles.

Until recently little was known about the detailed small scale structure of these films - now new techniques are allowing physicists to recreate these astrophysical wastelands in the hunt for the origin of life.

Julyan Cartwright, a specialist in ice structures at the Andalusian Institute for Earth Sciences (IACT) in Span thinks that the existence of life-like biomimetic structures in ice suggest that nature may well have copied physics. It is even possible that while ice is too cold to support most life as we know it, it may have provided a suitable internal environment for prebiotic life to have emerged.

“It is clear that biology does use physics,” said Cartwright. “Indeed, how could it not do? So we shouldn't be surprised to see that sometimes biological structures clearly make use of simple physical principles. Then, going back in time, it seems reasonable to posit that when life first emerged, it would have been using as a container something much simpler than today's cell membrane, probably some sort of simple vesicle of the sort found in soap bubbles.”

Using quick freezing techniques coupled with sophisticated scanning electron microscopy techniques, Cartwright and his team are creating ice films in cold conditions similar to outer space and observing the detailed molecular organisation. They found that ice under certain conditions produces biomimetic forms with shapes like palm leaves or worms, or even at a smaller scale like bacteria.

This led Cartwright to point out that researchers should not assume that lifelike forms in objects obtained from space, like Mars rock, is evidence that life actually existed there. “If one goes to another planet and sees small wormlike or palm like structures, one should not immediately call a press conference announcing alien life has been found,” said Cartwright.