QUESTION:
Is there a field for the study of microbiology on other planets?

ANSWER from Jack Farmer on December 30, 1997:
The field of Exobiology, which seeks to discover life elsewhere in the
Cosmos, is still in its infancy as a science. Because we only know of life
on one planet, namely, our own, some have described Exobiology as that
science which has yet to discover what it purports to study. While to some
extent this is true, there is a lot more to the discipline of Exobiology
than meets the eye.  Much of our progress in Exobiology has come from
attempts to understand the conditions necessary for the origin of life on
our own planet. Because of the synergistic nature of science, these advances
have propelled other fields forward as well.

Understanding how life may have developed on Earth requires a knowledge from
a diverse array of fields of science, including Geological stsudies of the
Earth and other planets in our solar system, Paleontology (the history of
life on Earth), the Biology, Ecology, and Evolution of ecosystems
(especially of microbial life forms which make up most of the life forms on
Earth). Through these studies we have come to better understand the
environmental extremes of life on our own planet (we are still making new
discoveries every week!), as well as the probable conditions required for
its origin and early evolution. What Exobiology ultimately seeks to do is to
use the information gathered from these and related disciplines to devise
strategies to explore for life elsewhere in the Cosmos. Much of that
exploration is going on right now as NASA continues to explore the other
planets in our Solar System.

In answer to your question, we have yet to discover life on other planets,
and so cannot yet study extraterrestrial life per se. But we can study past
life on Earth (through paleonlology) and present life (through biology) in
ways that have direct relevance for exploring for life elsewhere. And as our
exploration proceeds, the focus of Exobiology will necessarily change,
building on each new experience. If we are eventually successful in our
search, and do discover extraterrestrial life, then I expect we will want to
turn our attention in Exobiology more toward comparative studies of
terrestrial and extraterrestrial life forms to understand the way(s) life
has evolved on other different worlds.

With the recent advances in technology we have been able to look out further
and further into the Cosmos. And we have been able to establish more of a
virtual human presence elsewhere in our solar system using robotic
exploration.  I believe we are on the verge of a real explosion in the
fields of Exobiology and Astrobiology. So, while Exobiology is in its
infancy as a science, I think it is fair to say it is a growing field,
primarily because of the new perspectives afforded by these recent
advancements in both new technologies and ideas. These advances have enabled
us to make many new discoveries in the past few years. Some of these new
discoveries include the existence of planets orbiting other stars,
observation (using the Hubble Space Telescope) of the birth of new stars
from dust and gas, the discovery of extreme forms of microbial life capable
of living in boiling water, in freezing brines, or in deep subsurface
environments that have no connection to the surface), the possibility
(however unlikely) of fossil microbial life in a Martian meteorite (see
latest issue of Scientific American), and the possibility of subsurface
oceans on Europa, just to name a few. If you are interested in reading an
overview of this, try an article penned by Yvonne Pendleton and myself that
appeared in Sky and Telescope Magazine in July 1997. The title of the
article is "Life: A Cosmic Imperative" and you should be able to find it on
the Web or at the library.

Jack Farmer