Alien microbes, stowed away on our returning space vehicles, could threaten this planet with deadly danger.
by Paul Foght
IF GULLIVER TRAVELS, life in our universe may be doomed, or at least altered beyond recognition. “Gulliver” is a one-and-one-half pound instrument package designed to be landed on Mars in a U.S. effort to detect life on our neighbor planet.
The threat that this space probe presents is very real and very understandable. It is the threat of contamination by microorganisms carried to Mars in or on the Gulliver mechanisms. Most biological scientists believe that microorganisms from the earth could survive in the Martian environment, and the environment might allow the earth-organisms to breed and multiply unhindered. Such unrestricted reproduction by even the simplest organism could completely alter the scheme of life on Mars in mere short hours.
More horrifying than the prospect of Mars overrun by migrant organisms from the earth is the fact the same tragedy can befall earth. Space scientists are relentlessly ambitious and they can be expected to move swiftly from landing their instruments on Mars to the more ambitious project of putting the package down on Mars and then bringing it back to earth. The organisms it returns to earth could well contaminate our entire planet.
The Gulliver life-detecting instrument will be sterilized before it is blasted off to Mars, of course. But serious questions as to the effectiveness of any sterilization procedures may be raised. The two things that make sterilization doubtful are, first, the incredible ability of living organisms to go on living in spite of the most drastic changes of environment, and, secondly, science does not know what kind of Martian life it is attempting to protect or to protect against.
Present plans for sterilization of the Gulliver mechanisms* are reported to require dry-heat sterilization at 134° C for 26 hours in conjunction with the use of ethylene oxide. All instruments and experiments must be able to withstand these preflight sterilization procedures.
These steps may or may not be adequate to subdue the spark of life in earth’s ubiquitous microorganisms. After all, life grows in both burning deserts and frozen arctic wastes. Viable microorganisms are reported to have been recovered from within manufactured plastic and electronic parts. Russian scientists have reported a mold developing on frozen sugar-beets. The microorganisms that formed the Russian mold were found to have created their own cozy, warm environment by locally warming their hole in the sugar-beet root with heat produced in the process of their breathing.
These evidences are cited to demonstrate the power of life. This power may be absolute, and if it is, total sterilization may be impossible and the importation of earth-produced mechanisms to other parts of our universe should be prohibited.
The second reason for doubting the ability of scientists to protect our neighbor planets from contamination is simply that they don’t know what they are trying to protect. It is possible that Mars may harbor completely novel life forms. The article Is There Life On Earth?, FATE, October 1962, suggests the possibility of forms based on silicon. The report on Gulliver in Science, October 12, 1962* * also speculates on the existence of life in solid state.
If science cannot predict what form of life exists on Mars, how can it possibly protect against doing irreparable harm to that life by dropping its contaminated little automatic visitor into the midst of Martian life? The first visits of the white man to North America introduced dis¬eases such as small pox that virtually decimated the population of an entire continent and left the surviving Indians helpless before invading colonists. Any stow-away microbes on the Gulliver will be free to wreak equal havoc among whatever life populates Mars.
The offensive weapons of such a stow-away are potent indeed. Even such stable compounds as the alumosilicates that compose more than half the Earth’s crust, and which easily resist sulphuric acid, are decomposed by special bacteria. Even granite is destroyed by the action of cilicate bacteria.
But the greatest threat that an organism presents when it transgresses and enters into a new environment, is the prospect that it will multiply endlessly in the ab¬sence of natural enemies. There are several well-known examples of this phenomenon among certain organisms of Earth. These include the invasion of the Great Lakes of North America by the sea lamprey after the opening of the Welland Canal in 1931 permitted ships to pass from the fresh water inland seas to the salt water oceans. Only 20 years later the parasitic lamprey had destroyed the vast lake trout populations of four of the five lakes and was attacking the Lake Superior survivors with great vigor. Twenty years seems a short time for a population to spread through¬out the nearly 95,000 square miles of Great Lakes, but it is a poor performance when compared to the theoretical abilities of other organisms. The Russians Oparin and Fesenkov have calculated the ability of living organisms to multiply under favorable conditions and have produced frightening figures. For example, the choleraic vibrio can produce in a single day 61 or 62 generations; 6.4 x 10 to the 28th power individual choleraic vibrio. Diatomea, the simplest form of sea¬weed, can produce five generations a day.
Under conditions of unimpeded reproduction these living organisms could cover the surface of the earth in an extremely short time: the choleraic vibrios in 1.25 days, the Diatomea in 16.8 days, the green plankton in approximately 168-83 days, the flies in 366 days, and the barnyard chickens in 15-18 years.
Since Mars is roughly only half the size of Earth, it is theoretically possible for a stow-away microorganism, growing at the rate of the choleraic vibrios on Earth, to completely cover the surface of the planet in just 15 hours.
And this threat to Mars becomes a similar threat to Earth the instant the first round-trip, surface-to-surface space probe re-enters the mere incubator for virile microbes Earth’s atmosphere. Earth, too, may imported onto the planet from outer yet be reduced to functioning as a space.
* Gulliver — A Quest for Life On Mars, by G. V. Lenin, A. H. Heim, J. R. Clendennmg, M. F. Thompson. Science, October 12, 1962.
* * Life In The Universe, by A. Oparin and V. Fesenkov. Twayne Publishers Inc., New York, 1961.