The name seems appropriate to the newly discovered class of comets bombarding Earth's upper atmosphere at the incredible rate of one every three to four seconds. While a thousand times smaller than classical comets, such as Halley, minicomets vastly outnumber their larger cousins. Louis Frank, of the University of Iowa, first suggested the existence of minicomets in the 1980's. He proposed them as an explanation for the dark spots on ultraviolet images of the upper atmosphere sent back from the Dynamics Explorer 1 satellite. Last May, however, Dr. Frank released images obtained by the Polar satellite in 1996 that have all but silenced his foes.
Ordinary meteors supply the dust particles around which the drops condense.
If Dr. Frank's numbers are correct, minicomets could also account for all of the world's oceans arising in about a billion years, extrapolating from the current influx rate. Even if his numbers are too large, minicomets still can be credited with supplying a significant portion of the planet's ocean water. Given the greenhouse effect, increased influx rates should result in increased temperatures. Carbon dioxide and methane are removed from the atmosphere by a combination of volcanic, tectonic, chemical, gravitational, and biological processes on the earth's surface. An extraterrestrial source for replenishment of these light chemicals would help balance their depletion, thus balancing Earth's surface temperature, a necessity for life support.