Life in interstellar dust
From New Scientist Magazine, 18 August 2007, issue 2617
Plasma Crystal Experiment,
Max Planck Institute for Extraterrestrial Physics
COULD life in deep space be made from mere inorganic particles of dust? According to a computer simulation, electrically charged dust can organize itself into spiral structures that behave in many ways like living organisms; reproducing and passing on information to one another.
"It has a lot of the hallmarks for how we define life," says Gregor Morfill of the Max Planck Institute for Extraterrestrial Physics in Garching, Germany. Morfill and colleagues simulated what happens to dust immersed in an ionized gas. The team found that the dust sometimes forms double helices, the same shape as DNA and, like DNA, they can store information.
We all instinctively know what types of things are alive: bugs, plants, animals, seaweed—it ’s all living stuff. And we instinctively know what is not living: rocks, dirt, gold—even water and fire, which move and change, are not living.
Our planet is the only place in the universe, that we know of, where life is found. What is so special about life?
Not so long ago, life seemed so different from non-life that people assumed it had to be made of different stuff. We now know that the materials that make up living creatures are exactly the same as those that compose inanimate substances: there is no special kind of matter that distinguishes living from the nonliving.
If we are made up from same type of matter that makes up the air, oceans, and mountains, then what is different about us, living things, from nonliving things? What is the special nature of living organisms? Is life a thing or a process, and how did it start? Are there rules that govern its existence, its form, its pattern, and its behaviors? If so, what kinds of rules?
On theory is that living matter has simply been organized in a certain way. It is the system of organization that makes it special. The parts themselves are not alive: it is how things behave, what they do and how they do it, that makes them alive.
Just as in the nonliving world, the spiral is a prevalent shape among living things—and for many of the same reasons: the spiral is easy to build and expand, and it is stable, strong, and flexible. Living spirals self-organize into shapes that are influenced by the same laws of gravity that influence the formation of whirlpools and galaxies.
“Living creatures make use of the structures and processes that are available: spirals, vortexes, branching systems, stripes. Both evolution and genetics can each in its own way, modify these structures and patterns, fine-tune them and put them together in new exciting ways.” Ian Stewart, text.