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long-lost Martian springtimes of three or four billion years ago, when
according to most researchers polar ponds and seas sparkled in the
once-thicker Martian air. Perhaps there would be answers as to why life had
never gotten much of a tentacle-hold on Mars, had never gone much beyond the
now-fossilized microbial forms scattered in buried rocks and sediments.
The drills labored year round, but the favorite time for fieldwork was in the
"warm" southern summer, when the sun wheeled all day above the horizon, eating
away the snowy veneer of carbon dioxide frost
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and revealing the permanent, dirty-white layer of frozen water trapped
underneath the sun, like a bright vulture.
Success of a poor sort had come in '25 when the drills hit a meter-thick
stratum of grayish soil that had a higher-than-average content of organic
materials, averaging just in the range of a few parts per billion an extension
of the layer Stafford had studied a decade before. Barely out of the noise.
Hardly evidence of ancient, teeming life, but enough to make scientists
twitch. Stafford had spent a year studying materials from the site. The layer
was 3.2 billion years old. Since the microbes were rarer below that layer, and
more abundant above, Stafford had concluded that the layer might mark the
climax of the fluvial period, when life got its start, but after which life
died out because of the declining conditions.
Polar research had continued unabated, Lena recounted. The main efforts were
to answer why, except for sporadic local anomalies, most rivers had stopped
running and the water had frozen three billion years ago. There were efforts,
both by drilling and by finding the oldest outcrops, to concentrate on the
strata laid down around that time.
Results of a different sort had come about ten weeks back, when two successive
drill bits shattered at a depth of five hundred meters. Initial speculations
of the geology team centeredaround massive nickel-iron meteorite fragments, or
some mysterious ore body. The splintering of two successively stronger drill
bits capable of penetrating such materials ended that speculation. Eventually,
imaging in the drill hole seemed to show a smooth, rounded surface, unmarred
by the drill bits. Chemical probes showed a metalloid structure rich in
titanium, silicon, and carbon, but failed to identify the precise composition
or molecular structure. This is when Stafford had been called by Lena, and the
secrecy lid had clamped down.
Eventual enlargement of the drill hole allowed more complete imaging, and
precarious human inspection revealed a horizontal-lying tube, a pipe about the
thickness of a man's body. It ran east-west. In every test they could devise,
the tubing proved impenetrable.
The next step had been to make another drill hole one hundred meters to the
east. It uncovered what appeared to be an eastward extension of the same
tubing. They couldn't keep drilling all over the pole to trace the extension
of the thing. Geophysical measurements from the surface were attempted, in
hopes of mapping the extent of the metal mass, but with no success.
By that time, still in early February, with the protocols in place, it was a
crash program with unlimited budget, to learn as much as possible within
ninety days. Sturgis and his security team had seized control of the operation
and ordered the most sensitive geophysical equipment sent from Mars City and
Phobos, piggybacked on other freight shipments so as not to attract attention.
The science team had gone along with it, choosing to interpret the ninety days
not as imposed secrecy but as the normal data development period before
publication.
Renewed attempts to detect the buried tubing with the new geophysical
equipment from Earth gave marginal results. But the drilling went quickly in
the soft-rock polar sediments. New holes sunk one, two, ten,twenty, fifty
kilometers to the east always hit the tubing. Where the tube crossed under the
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