Science: Life on Mars?

  • Share
  • Read Later

The near approach of Mars last summer was a sad disappointment to astronomers. A dust storm that veiled the planet's disk foiled the fanciest apparatus. But last week's meeting of the Astronomical Society of the Pacific at Flagstaff, Ariz, heard a few bits of Martian news that had shown through the dust curtain.

Telltale Band. Most important was proof that organic (carbon-hydrogen) compounds probably exist on Mars. Dr. William Sinton of the Smithsonian Institution started with the fact that compounds containing carbon, when joined to hydrogen, absorb infra-red radiation with a wave length of 3.46 microns. His first step was to look for this absorption band in infra-red light reflected from dry leaves, lichens and mosses, which are made almost entirely of carbon-hydrogen compounds. It showed up strongly.

Then Dr. Sinton hitched a supersensitive infra-red detector to Harvard's 61-in. telescope and looked for the same absorption band in sunlight reflected from Mars. Many observations were necessary because of the feebleness of Martian light, but at last the band appeared. Apparently, something on Mars absorbs infra-red in the same way that earthside vegetation does. Dr. Sinton thinks his observation is strong evidence that Mars has living organisms whose bodies are made of compounds containing carbon and hydrogen.

Another "observation" of Martian life needed no telescope. Dr. Hubertus Strughold, chief of the Air Force's Department of Space Medicine, wrote a book a few years ago about Mars as an environment for living organisms (The Green and Red Planet, TIME, Aug. 24, 1953). His general conclusion was that the Martian climate is not too tough for some sort of hardy life. He suggested that this be proved by setting up a "Mars chamber," where rugged terrestrial organisms could be subjected to Martian conditions.

Mars Chamber. Last week Dr. Strughold reported at Flagstaff that this experiment has been performed successfully by Dr. Roland B. Mitchell and Lieut. John A. Kooistra Jr. of the Air Force School of Aviation Medicine. They collected soil samples from the high slopes of Mt. McKinley, the Painted Desert and the Grand Canyon, where the climate in some respects is almost as tough as on Mars. They put the samples in jars and replaced the oxygen-rich earthly air with dry nitrogen. They lowered the moisture content to below 1% and reduced the pressure to 1.2 Ibs. per square inch to simulate the thin Martian atmosphere.

Every day (Martian days are about as long as earth days), Mitchell and Kooistra warmed their jars to 70° F., the temperature of noontime in the Martian tropics, and tucked them away for the night in a refrigerator at the below-freezing temperature of the Martian night.

After many cycles of this, they opened the jars. The dry soil inside was still alive with bacteria which had triumphantly survived "Martian" dryness and cold. The hardiest strains could reproduce during warm spells when the moisture content of their soil was only two-fifths of 1%. When the moisture rose above 1%, as it may during the Martian spring when the icecap melts or evaporates, the bacteria throve.

  1. Previous Page
  2. 1
  3. 2