An analysis of "atmospheric holes" produced by small comets
in images of the Earth taken by a camera aboard NASA's Polar
spacecraft shows a remarkable seasonal variation. Two physicists at
the University of Iowa, Louis A. Frank and John B. Sigwarth, have
found that the influx of small comets into the Earth's atmosphere is
10 times greater in early November than in mid-January, when the
small comet rate diminishes dramatically.
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Most significantly, this is the same seasonal variation they
discovered 16 years ago in the atmospheric hole data found in images
from a different camera aboard a different
spacecraft, Dynamics Explorer-1, which traveled a different orbit
than the Polar spacecraft. Frank regards this new analysis a fatal
blow to the continuing claims of critics that
atmospheric holes are nothing but "instrument
noise."
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These new results also suggest that the small comets storms are at
least 40 years old. While the Polar spacecraft provides data for the
1990s, and the Dynamics Explorer-1 spacecraft gathered data during
the 1980s, the oldest data set showing the influx of small comets
into the Earth's atmosphere dates back to 1955. Using forward
scatter radar, two Canadian scientists, E. L. Vogan and L. L.
Campbell, had found exactly the same seasonal variation, a November
high and January low, in their non-shower, or sporadic, radar meteor
rate.
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