Evidence of Small Comet "Storms"
Confirmed by NASA's Polar Spacecraft

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. Figure D
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." Figure E
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. Figure F

Why the atmospheric hole rate should correlate so well with the meteor rate measured by forward scatter radar is no mystery. After all, small comets are just a part of the meteoric dust and debris that orbits the Sun and falls into the Earth's atmosphere on a daily basis. Because the weakly bound small comets and mantle debris are expected to produce ionization at higher altitudes than stony or iron meteoroids, forward scatter radar--which is much more sensitive to ionization at higher altitudes than backscatter radar--is ideally suited to reflect the infall of small comets. (Backscatter radar events, on the other hand, are dominated by the infall of iron and stony meteoroids.) So with this 1955 radar data set included,the current influx of small comets appears to have continued at least from 1955 to 1998, or more than 40 years.

This finding on seasonal variations in the appearance of atmospheric holes and the associated small comets adds to the mounting evidence for the reality of the phenomenon. "These observations are truly exciting," says Frank," and they prove conclusively that the atmospheric holes are real."

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