Life Spreads Through Universe in Cosmic Dust, Paper Suggests

Astronomer Carl Sagan may have been more right than he knew when he quipped that "we are made of star stuff."

In a not-yet-peer-reviewed research paper Georgian Free University of Tbilisi astrophysicist Z.N. Osmanov offers a fresh look at an established theory: that life on Earth, and potentially elsewhere in the cosmos, is the result of the same sort of tiny particles that create stars and planets or other celestial bodies.

If that's right, as Osmanov claims, there may be more planets containing this life-breathing star stuff than we could possibly imagine.

The concept also known as "panspermia" denotes — as the "sperm" in its name suggests — that the seeds of life can make their way between worlds, perhaps on asteroids or comets.

In his paper, Osmanov, who is associated with SETI Institute, takes the theoretical concept a step further. Using the philosophical equation formulated by famed scientist Frank Drake, he posits that there is an exponentially huge number of planets that could contain the seeds of life: a number to "the order of 3×107."

"This value is so huge that if dust particles can travel a distance of the order of several hundred light years, one can conclude that the Milky Way, with a diameter of 100,000 light years, should be full of complex molecules distributed throughout the entire galaxy," he wrote.

Life-containing dust could, Osmanov continues, travel "by means of the solar radiation pressure," and per his theory, those "small dust grains containing live organisms could travel to the closest star system, Alpha Centauri, in nine thousand years."

To be clear, the astrophysicist is not arguing that there are an infinite number of planets where life actually exists. 

Rather, there could be an exponential number of worlds that could potentially support so-called "primitive" life, or the kinds of single-celled organisms that led to more complex creatures here on Earth.