Tuesday, May 27, 2008

Contamination of Mars by Man

With all the excitement surrounding the NASA Phoenix Mars Lander project and the in depth experiments to be run looking for organic compounds in the permafrost layer that could have represented some form a microbial life or determine if the Martian arctic soil could support life, one needs to really analyze the possible contaminations to any experiment performed on the surface of Mars.

Mars Soil

The Mission Begins

This image shows a polygonal pattern in the ground near NASA's Phoenix Mars Lander, similar in appearance to icy ground in the arctic regions of Earth.

Phoenix touched down on the Red Planet at 7:53 p.m. Eastern Time, May 25, 2008, in an arctic region called Vastitas Borealis, at 68 degrees north latitude, 234 degrees east longitude.

This is an approximate-color image taken shortly after landing by the spacecraft's Surface Stereo Imager, inferred from two color filters, a violet, 450-nanometer filter and an infrared, 750-nanometer filter.

Image Credit: NASA/JPL-Caltech/University of Arizona

In the National Aeronautics and Space Administration press kit dated May 2008, we have the following quotes.

2. Determine if the Martian arctic soil could support life.

Life as we know it requires liquid water, but not necessarily its continuous presence. Phoenix will investigate a hypothesis that some ice in the soil of the landing site may become unfrozen and biologically available at times during the warmer parts of long-period climate cycles. Life might persist in some type of dormant microbial form for millions of years between thaws, if other conditions were right.

The spacecraft is neither equipped nor intended to detect past or present life. However, in addition to studying the status and history of water at the site, Phoenix will look for other conditions favorable to life.

One condition considered essential for life as we know it is the presence of molecules that include carbon and hydrogen. These are known as organic compounds, whether they come from biological sources or not. They can be produced without life, but they include the chemical building blocks of life, as well as substances that can serve as an energy source, or food, for life. Phoenix would be able to detect small amounts and identify them. The two Viking spacecraft that NASA landed on Mars in 1976 made the only previous tests for organic compounds in Martian soil, and found none. Conditions at the surface may be harsh enough to break organic molecules apart and oxidize any carbon into carbon dioxide. Phoenix will assess some factors in those oxidizing conditions and will check for organic chemicals below the surface, as well as in the top layer. Organic chemicals would persist better in icy material sheltered from sunshine than in surface soil exposed to harsh ultraviolet radiation from the sun. Organic compounds have been found in some meteorites that hit Earth. Scientists reason that meteorites raining onto Mars over the eons have delivered organic compounds to that planet, too. Whether these compounds can persist in a Martian environment is an important question in whether the environment would have been favorable or hostile to life.

Phoenix will also be checking for other possible raw ingredients for life. It will examine how salty and how acidic or alkaline the environment is in samples from different layers. It will assess other types of chemicals, such as sulfates, that could be an energy source for microbes.

NASA Phoenix Mars Lander Press Kit PDF File

In another article we read early on the concern of contamination of Mars being introduced by man titled:

Biological contamination of Mars. I. Survival of terrestrial microorganisms in simulated Martian environments.

Scher S, Packer E, Sagan C.

Space Sciences Laboratory, University of California, Berkeley, California, USA.

It has been postulated that the accidental introduction of terrestrial microorganisms to other planets during the course of space exploration might impede or bias the detection of organic matter and possible indigenous organisms, and thereby confuse subsequent studies of extraterrestrial life. To assess the likelihood of biological contamination of Mars, we have applied the principle of natural selection on a laboratory scale. Terrestrial microorganisms were collected from a variety of environments, including regions of high alkalinity, low mean daily temperature, and low annual rainfall. The air-dried soils were then subjected to a simulated Martian environment involving 12-hour freeze-thaw cycles from about -60 degrees C to about +20 degrees C; atmospheres of 95 per cent nitrogen, 5 percent carbon dioxide and low moisture content: < or =" 0.1" Life Sci Space Res. 1964

Now, how are we to positively know that any type of experiments performed on the Mars surface haven't been compromised in some way? How do we know that we haven't contaminated the results of any experiment just by our very means of getting to the surface of Mars itself? How do we know we haven't brought microbes or carbon and hydrogen along for the ride with the Mars lander that won't affect the experiments? We are making assumptions about assumptions. We are assuming that everything has been sterilized to neutral. Remember what they say about assuming... Never ASSUME or you make an ... out of you and me.

Science is the effort to understand, or to understand better, how the physical world works, with observable evidence as the basis of that understanding. It is done through observation of phenomena, and/or through experimentation that tries to simulate events under controlled conditions. Source Wikipedia

While certain constants can be controlled in all experiments, there are however certain variables that can never be completely controlled. Additionally, having any false assumptions can affect the interpretation of the results.

By-the-way, are you getting the results you want with business website online? Are you bringing in new customers? Get a free website marketing analysis today. Start getting Internet marketing results today.

No comments: