The Rock From Mars (53 page)

“You can’t tell
• Elizabeth K. Wilson, “Bitten by the Space Bug,”
Chemical and Engineering News
(Nov. 18, 1996): p. 29.

At least one avid
• Cosmochemist John Kerridge, as quoted in Charles Petit, “Pieces of the Rock,”
Air and Space
(Apr.-May 1997): p. 40.

The peripatetic Ralph
• Kerr, “Life on Mars: Martian ‘Microbes’ Cover Their Tracks.” Harvey and colleague John Bradley also found that most of the magnetite crystals were perfectly aligned in three dimensions with the surrounding carbonate in a way that argued against biological origins.

Of all the challenges
• Author interview with McKay. See also Beatty, “Messenger from Mars,” p. 39.

None of these disagreements
• Author interviews with Steele.

Mary Fae McKay was
• Author interviews with Mary Fae McKay.

Some considered the
• For Blanchard comments, see Kathy Sawyer, “Digging into Data on Mars Life Claim; Research Community’s Verdict Is Years Away,”
Washington Post,
Mar. 20, 1997, p. A3.

Some weeks after this
• David Salisbury, “Debate Over Evidence for Martian Life in Meteorite Rages On,”
Stanford News,
May 29, 1997.

The opposition was expressing complaints similar to Zare’s. Ralph Harvey, for one, told the author that he thought poorly chosen peer reviewers were allowing a number of unworthy papers to get published. (As the years and papers rolled by, he would come to feel strongly that too many people who knew next to nothing about meteorites, Bill Schopf included, were involved as referees on proposed papers and in other key roles in the debate. “I don’t see much of a sign . . . that they chose really competent people to review them,” he said in November 2001, following another round of papers on the rock.) Like Zare and others, he also felt that his involvement in the “media circus just derailed my research for a while.” Other people were publishing ideas that Harvey and company had come up with earlier but failed to publish, he said, because “I had been spending a little bit too much time giving talks.”

The Brits would soon determine
• A. Steele et al., “Investigations into an Unknown Organism on the Martian Meteorite Allan Hills 84001,”
Meteoritics and Planetary Science,
vol. 35 (2000): pp. 273–81; see also A. Steele, J. Toporski, D. Goddard, D. Stapleton, and D. S. McKay, “The Imaging of Terrestrial Microbial Contamination of Meteorites,”
Microscopy and Analysis,
vol. 83 (2001), pp. 5–7; A. Steele et al., “F Atomic Force Microscopy Imaging of Fragments from the Martian Meteorite ALH84001,”
Journal of Microscopy,
vol. 189 (1998), pp. 2–7; A. Steele et al., “Terrestrial Contamination of an Antarctic Chondrite (Abstract),”
Meteoritics and Planetary Science,
vol. 33 (1998): p. A149; A. Steele et al., “The Contamination of Murchison Meteorite,”
Lunar and Planetary Science
vol. 30 (1999): Abstract 1293, Lunar and Planetary Institute, Houston (CD-ROM); A. Steele et al., “The Microbiological Contamination of Meteorites: A Null Hypothesis,”
Lunar and Planetary Science,
vol. 31 (2000), Abstract 1670, Lunar and Planetary Institute, Houston (CD-ROM); Jan Toporski et al., “Contamination of Nakhla by Terrestrial Microorganisms,”
Lunar and Planetary Science,
vol. 30 (1999), Abstract 1526, Lunar and Planetary Institute, Houston (CD-ROM).

Steele delivered the
• Author interviews with Steele and McKay; see also A. Steele et al., “Imaging of the Biological Contamination of Meteorites: A Practical Assessment,” Abstracts of the Thirtieth Lunar and Planetary Science Conference, Mar. 15–19, 1999, Lunar and Planetary Institute, Houston. The paper noted that the detection of the terrestrial organisms and their products in the rock “do not necessarily negate the possibility that it contains evidence for early life on Mars. However, it becomes more challenging to separate such evidence from the terrestrial contamination.” The evidence also raised the possibility that the entire framework of fractures leading deeper into the meteorite might have been contaminated—though no trace of Earth bugs deep inside the rock had been found in careful searches.

Steele and his coworkers
• They used scanning electron microscopes of two types (typical and environmental) and an atomic force microscope.

Also, another group
• Jeffrey Bada et al., “A Search for Endogenous Amino Acids in Martian Meteorite ALH84001,”
Science
(Jan. 16, 1998): pp. 362–65. See also L. H. Burckle and J. S. Delaney, “Terrestrial Microfossils in Antarctic Ordinary Chondrites,”
Meteoritics and Planetary Science,
vol. 34 (1999): pp. 475–78. This group reported detecting in the meteorite diatoms in cracks, which they said must have been blown inland over the ice, along with dust. They concluded that contamination with micrometer-sized organisms might be widespread in Antarctica.

In the past, the
• A. Steele et al., “Imaging of the Biological Contamination of Meteorites: A Practical Assessment.”

As Steele would write in
• A. Steele et al., “Imaging of the Biological Contamination of Meteorites.”

Steele and company
• Author interview with Steele. As Steele’s team continued sorting out what was what in the rock, they found a strange chemical signature that seemed to be a sign of biological activity—a so-called biomarker—because they saw it only when there was cellular debris or other biology present. After what Steele deemed a ridiculous amount of work, they finally figured it out. The mystery matter turned out to be—cue Dustin Hoffman
—plastic!
It seemed that before the curators sent out meteorite samples to researchers, they routinely heat-sealed the container bags. There had been a small leakage of the plastic into the samples. What’s more, contaminating bacteria considered the plastic to be food. So the Allan Hills meteorite had not only been contaminated by bacteria, it had been contaminated by plastic and the plastic was nourishing the bacteria.

Plastic was not the only such oddity. Steele also discovered fungi growing on a sample inside a plastic bag. The team traced it to Building 31. It turned out the air-conditioning system had a heat exchanger on the roof, and the contamination—in the form of the fungus penicillium, a green bread mold—was leaking into the lab through the unfiltered ducts. NASA put in a HEPA filter, which was supposed to be changed every three months. In Steele’s view, managers did not have a rigorous enough plan to see that this was done. Space center officials considered the problem corrected and reported that it had not affected critical laboratory results. In any case, Steele still considered the NASA curation facility the best in the world.

These techniques, called
• Immunoassay tests were used to measure biological compounds in nearly all areas of clinical laboratory science and basic biomedical research. The technique depended on the specificity of antigen-antibody interactions and the sensitivity of chemical reactions such as enzymatic activity, radioactive decay, fluorescence, and luminescence.

In any case, the
• See www.masse.co.uk/. The MASSE project was intended to seek evidence of terrestrial contamination, prebiotic chemicals, and organic biomarkers for extinct or extant life on Mars. It was to employ both in vivo and in vitro techniques to produce, isolate, and use antibodies, in combination with immunofluorescence and developing protein-array technology.

One of the schmoozers
• Author interview with Kerridge at the cocktail party.

Not far away from
• Michael Ray Taylor,
Dark Life
(New York: Scribner, 1999), pp. 240–41.

In the last years of
• Richard Kerr, “Requiem for Life on Mars? Support for Microbes Fades,”
Science
(Nov. 20, 1998): p. 1398; see also Dick and Strick,
Living Universe,
p. 196.

Some (though not all
• Author interviews with the McKay group. See also Steven J. Dick and James E. Strick,
The Living Universe
(New Brunswick, N.J.: Rutgers University Press, 2004), p. 190.

The rock was indeed
• Tim Jull, et al., of the University of Arizona, did a study of the isotopic composition of the carbon in the meteorite which Dick Zare said “does indicate a degree of terrestrial contamination that is much greater than I suspected was present.” The study showed that just 20 percent of the organic material was extraterrestrial, but it did not indicate where this portion was located in the meteorite. Zare said that although he did not believe the research “refutes the basic contention in our original paper,” it “does cast new doubt on our hypothesis.” See David F. Salisbury, “Latest Research Casts New Doubt on Evidence for Fossil Life in Martian Meteorite,”
Stanford News,
Jan. 14, 1998.

The McKay regulars couldn’t
• Author interviews with the McKay group.

Author interview with Allan Treiman, concerning the factions within factions. See also Allan Treiman, “Microbe in a Martian Meteorite? An Update on the Controversy,”
Sky and Telescope,
vol. 97 (April 1999): pp. 52–58. (One example of the branching internal disagreements: regarding the temperature at which the carbonates—and the magnetic crystals in them—had formed, people who agreed that conditions were too hot for life differed about whether the rock was in those high temperatures for a long time—under high pressure, deep in the crust of Mars—or whether the rock had experienced heat and high pressure for only a few microseconds as the result of an impact shock, when an asteroid or comet slammed into Mars. Then there were others who agreed that the carbonate globules were deposited from water at relatively low temperatures, but that there was no biology involved at that time. The magnetite crystals and organics—the PAHs—formed later, they contended, as the carbonates decomposed, possibly in connection with volcanic events.)

McKay group antagonist Ralph
• Author interview with Harvey.

“You have to understand
• Author interview with Gibson.

As the controversy
• In an author interview, Ralph Harvey argued the point from the opposite direction. If the McKay group’s original premise was that all the evidence taken together, not any single line of evidence, made the case for biology in the rock, then as most of the lines of evidence weakened under attack, in his view the group’s “holistic” case was “just gone.”

Steele was among those
• Author interview with Steele.

Simon Clemett, for another
• Author interview with Clemett.

Painful as it could get
• Derek Sears and William Hartman, “Conference on Early Mars,” Houston, April 24–27, 1997,
Meteoritics and Planetary Science,
vol. 32 (1997): pp. 445–46. See also Dick and Strick,
Living Universe,
p. 195, which quotes the editorial.

Steele would work in
• Steele was hired at Carnegie by Wes Huntress, the former top lieutenant to Dan Goldin who had watched the story of the rock unfold in official Washington and was now director of the institution’s Geophysical Laboratory. Steele also secured a research fellowship at Oxford University, in addition to his affiliation with Portsmouth University. In the United States, he had a tie to Montana State University, which gave him access to instruments he needed. He also had consultant status with NASA contractor Lockheed Martin.

CHAPTER THIRTEEN:
bingo

In fact, Thomas-Keprta
• Author interviews with Thomas-Keprta and other members of the McKay group were the basis for the account of this incident.

Those seductive magnetic
• “Some would call this the smoking gun,” McKay, Gibson, and Thomas-Keprta wrote, referring to the magnetic crystals, in a summation of the state of play on the rock presented at the July 1999 Fifth International Conference on Mars in Pasadena, California. See McKay et al., “Possible Evidence for Life in ALH84001,” p. 3, at: http://www.lpi.usra.edu/meetings/5thMars99/pdf/6211.pdf.

The work of the McKay
• A crystal is a solid form bounded by several flat, smooth planes, or faces. This form is adopted by a chemical compound (mineral) when passing, under certain conditions, from the state of a liquid or gas to that of a solid. There is no geometry to study when the compound is liquid or gas, because the atomic forces that bind the mass together in the solid state are not present.

Sensitive instruments aboard
• J. E. P. Connerney et al., “The Global Magnetic Field of Mars and Implications for Crustal Evolution,”
Geophysical Research Letters,
vol. 28 (Nov. 1, 2001): pp. 4015–18. The onboard magnetometer showed that the ancient upland crust of Mars’s southern hemisphere was magnetized, an indication of a past global magnetic field. Planetary scientists then used established dating techniques to estimate that the Martian magnetic field had disappeared about 3.7 or 3.8 billion years ago.

It was a point of
• Author interview with Ralph Harvey; Richard Kerr, “Martian ‘Microbes’ Cover Their Tracks,”
Science
(Apr. 4, 1997): pp. 30–31; Dick and Strick,
Living Universe,
p. 193.

Wary that this
• Among the reasons for ruling out terrestrial contamination in this population of magnetites, Gibson said, were the following: the crystals were deeply embedded in the carbonate globules in the meteorite, and magnetite-producing bacteria preferred low-oxygen environments, and therefore would not likely have lived in Antarctic meltwater.

One reason was that the
• Author interview with McKay.

“We take our cues
• Author interview with Thomas-Keprta.

With Thomas-Keprta as lead
• Kathie L. Thomas-Keprta, D. A. Bazylinski, J. L. Kirschvink, S. J. Clemett, D. S. McKay, S. J. Wentworth, H. Vali, E. K. Gibson Jr., and C. S. Romanek, “Elongated Prismatic Magnetite Crystals in ALH84001 Carbonate Globules: Potential Martian Magnetofossils,”
Geochimica et Cosmochimica Acta,
vol. 64 (Dec. 1, 2000): pp. 4049–81. The international research journal for geochemistry and cosmochemistry is sponsored by the Geochemical Society and the Meteoritical Society. (The prime mover behind its instigation in the late 1940s was Paul Rosbaud, a colorful editor who spied on the Nazis for the British government during the war.)