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Thousands of scientists in many disciplines of
physical sciences such as geology, oceanography and planetary studies
found the proposed existence of small comets as simply folly. Indeed it
is fair to say that the only scientists to accept their existence were
the three authors of the original two papers, research scientist John
Craven who was in charge of the camera design, Sigwarth and myself. The
criticism and emotional reactions began immediately with their
publication. Noting that the publication date was April 1, 1986,
reporters from newspapers, including the New York Times, quickly
called to confirm that the content of the papers was simply an
"April Fool's joke". The attitude of the scientific community
was epitomized by the following consensus opinion:
"One has as much chance to see a small comet's shadow in Earth's
atmosphere as to be able to show that a pig flies by seeing its shadow in
moonlight."
This is a clever retort but one must give credit to the source of
inspiration, a Weekly World News report from Jakarta, Indonesia
reproduced in Figure 4 [below] of "Farmers shot up an entire herd of
flying pigs as the migrating porkers flew over their rice paddies."
In the face of a multitude of such criticisms it would have been
advantageous to our professional careers if we could declare that the
atmospheric holes were just due to camera noise in the images from the
Dynamics Explorer spacecraft. But this was not possible for four major
reasons. Firstly most of the holes moved from dusk to dawn across the
dayside atmosphere. The camera would have no internal knowledge of such
favoritism. Secondly and thirdly, the atmospheric holes favored the late
morning hours and also became larger as the spacecraft moved to lower
altitudes, respectively. Again the camera had no knowledge of what part
of the atmosphere was being viewed or of the spacecraft position. And
finally the frequency of atmospheric holes was correlated with the
seasonal variations of meteors as viewed with a ground-based radar
station. No retreat from the reality of atmospheric holes was possible.
The new cameras. Images from cameras on other spacecraft which
could confirm the existence of atmospheric holes were not available until
the launch of the Polar spacecraft on February 24, 1996. The reasons for
this were several: the images must be taken in the special ultraviolet
window, provide a view of a large section of the daylit atmosphere, and
have sufficient resolution in order to detect an atmospheric hole. The
intervening interval of 10 years since the report of images from Dynamics
Explorer 1 was a period of relatively quiescent activity during which the
scientific community became further convinced that the atmospheric holes
in the images were simply due to camera noise. In this quiet atmosphere
another set of auroral cameras was being constructed at the University of
Iowa for the Polar spacecraft. The capabilities for the detection of
atmospheric holes, and of the small comets, were also objectives of these
cameras. These cameras were the most sophisticated scientific instruments
ever built at the University of Iowa. If atmospheric holes and the small
comets existed, the resolutions and capabilities of these cameras would
leave no doubt.
The scientist in charge of the design and construction of the
sophisticated Polar cameras was John Sigwarth who now was a senior
research scientist. Of the original three researchers in the efforts
These new cameras were capable of greatly extending the previous
observations with Dynamics Explorer 1 in three important, independent
ways. First of all the atmospheric holes could be observed with much
greater spatial resolution which provides confirmation beyond any
reasonable claims of "camera noise". Secondly, the sky in the
vicinity of our planet could be monitored for bright trails due to the
glow of oxygen from the disruption of some of the comets at very high
altitudes of thousands of miles. Thirdly, the new cameras would allow
optical detection of the fragments of water molecules as the cometary
clouds plummeted into the atmosphere.
The Polar spacecraft and its cameras were successfully launched and the
complex process of turning on these sophisticated cameras proceeded
during the month of March 1996. John Sigwarth was at the control center
at NASA's Goddard Space Flight Center in Greenbelt, Maryland during this
critical period. I will always remember a telephone conversation with
John during which a lengthy discussion of camera voltages, currents and
temperatures occurred. At the end of this conversation, John quietly said
"Oh, yes, by the way, the atmospheric holes are clearly present in
the images."
Although John and I knew that the above three confirmations were
successful by late Fall of 1996 it was clear to us that we needed some
"quiet time" to achieve a careful, thorough analysis. Our
silence during this period of over a year after launch was greeted by
most scientists with relief that the atmospheric holes and small comets
must not exist. When the results were finally reported at a
NASA-supported press conference at the American Geophysical Union meeting
during May 1997 there was great turmoil and confusion in the scientific
community and the announcements raced like a wildfire through the press.
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with the cameras on board Dynamics Explorer 1, John Craven has departed
to accept a faculty position at the University of Alaska at Fairbanks.
The new Polar cameras were large and heavily instrumented with onboard
computers. These cameras are shown in the photograph of Figure 5 [left].
The person in the "space suit" is indeed John Sigwarth and he
is sitting at the top of the 100-foot tall gantry which allows him to
view the cameras. The cameras are encased within the largest rectangular
box in front of him. The rest of the spacecraft is hidden below the
cameras. The spacecraft and the cameras would be soon launched into a
high-altitude orbit above the Northern Hemisphere. It would have a superb
view of both the auroral lights and of the sunlit atmosphere.