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Out There
by Louis A. Frank
and Patrick Huyghe
I spent more than a year answering the objections of critics. But I didn't convince them. It was 10,000 to 1 -- actually 2, myself and John Sigwarth, whose task as my graduate student assistant had been to help me resolve this black-spot mystery. "We have taken a representative poll of current opinion in this field," an editor at Nature wrote in rejecting a small-comet paper we submitted to them in 1988, "and the verdict goes against you." It was my first encounter with taking polls as a way of doing science.

Now, a decade later, many of those who had "voted" against us are changing their minds. In May at a meeting of the American Geophysical Union, we presented images acquired by our ultraviolet camera aboard NASA's Polar spacecraft, a satellite sent up to study the Sun's effects on the Earth's environment. This camera, too, had picked up the black spots in the Earth's sunlit atmosphere. And this time there was no doubt; these black spots or atmospheric holes, as we called them, occurred in clusters of pixels or picture elements, not single pixels as in the Dynamics Explorer images. The phenomenon could not be due to instrumental artifacts. We could also see these black spots expanding and moving as they entered Earth's atmosphere. And the filters on our visible-light camera confirmed that these objects consisted of water -- enough water to produce clouds of water vapor 50 miles across, high in the atmosphere.

The new evidence stunned many of our former critics into admitting that we had been right. The University of Michigan's Thomas Donahue, one of the world's leading experts in atmospheric science, said so, as did Robert Meier, a space physicist from the Naval Research Laboratory in Washington. "I guess I'll just have to swallow crow," wrote one detractor. These former critics now agree that these objects are indeed water-bearing, but they don't want to call them small comets because they don't have the dust that the large, well-known comets do. That's okay. Call them "cometesimals" if you want -- that's the term Donahue prefers -- but the fact remains: They carry lots of water just like the large comets, and they are millions of times smaller than Hale-Bopp and Halley.

At first glance, this apparent resolution to the small-comet affair would seem worthy of applause -- the scientific process of debate, peer review and criticism would appear to have functioned admirably. But the gap between appearance and reality is a large one. After I presented my findings on the small comets in 1986, the scientific community did its best to extinguish my career. In the past decade, I have been unable to get any other projects off the ground. Before the small-comet findings became public, my success in this regard was envious; I was able to get instruments on board several major spacecraft -- Polar, Galileo and Geotail. But after my small-comet announcement, I got nothing. I had my ongoing projects, such as the one on Polar that eventually produced the confirmatory data. But the new projects I proposed went nowhere -- even those that had nothing to do with small comets.