Life on Mars Means Life on Earth (for NASA anyway)

Science 1996;273:864-866,924-929


Since the first moon landing in July 1969, the space science program of the National Aeronautics and Space Administration (NASA) has not really captured the imagination of the American public. And budget cuts are looming.

NASA's $2 billion space science program is being cut to $1.8 billion in 1997. And further cuts over the next five years are in the long-term federal budget plan.

What to do? Simple. Take advantage of the public's fascination with extraterrestrial life. And in a transparent effort to pump up its budget, NASA recently announced that it uncovered "evidence for primitive life on early Mars" in a softball-sized meteorite found in Antarctica in 1984.

Perhaps. But NASA may have only found evidence of mundane chemical activity.

As presented in an article contained in Science (where the original NASA finding is published), here's the evidence (and alternative explanations offered by other scientists) for the NASA claim:

Polycyclic aromatic hydrocarbons (PAHs) were found inside the meteorite. PAHs are large, complex organic molecules. The origin of the PAHs is assumed by NASA to be the breakdown of organisms that lived in the Martian rock.

PAHs have not been found in other Antarctic meteorites. The dearth of PAHs in the outer rind suggest that they didn't leak in from an outside source.

But PAHs are commonplace in some interplanetary dust, and many organic rich molecules from asteroids.

Also, the PAHs may simply be contamination from Earth. In the 1960s, a few researchers reported that a meteorite had yielded organic matter that appeared to be biologically produced. As it turned out, the material was actually degraded ragweed pollen.

The PAHs could have been formed from simpler compounds on Mars that never evolved chemically into living organisms.

Mineral deposits, including carbonate globules, were found within the rock. NASA scientists liken these to carbonate globules forming in the laboratory and freshwater ponds as bacteria alter the environment.

Warm fluids circulating through the Martian crust might have deposited the same sequence of minerals without any help from living organisms.

Two other minerals, magnetite and pyrrhotite, were found together in regions of the rock. The precipitation of these minerals together has been observed in many biogenic systems.

No alternative explanation was offered for this point.

Electron microscopy shows structures that look like microfossils.

That the structures are fossils is an interpretation, and is not supported by independent evidence that these forms were once living. Little blobs on rocks can be formed with all sorts of chemical precipitates.

In the short-term, NASA will try to slice open a putative microfossil to see if it has a cell wall. All Earthly bacteria have cell walls, and fossilized cell walls might retain traces of organic matter.

To me, the interesting part is the finding of the PAHs, chemical compounds that the U.S. Environmental Protection Agency (EPA) considers to be cancer-causing. Maybe the PAHs are the reason life no longer exists on Mars.

So NASA better watch out. EPA might figure Mars should be a Superfund site. And EPA is much better at garnering budget dollars and political support than NASA's space science program!

Material presented on this home page constitutes opinion of the author.



Copyright © 1996 Steven J. Milloy. All rights reserved. Site developed and hosted by WestLake Solutions, Inc.

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