50. Meteor dynamics

Abstract

Whipple:It is quite impossible for me to make a proper summary of the many major contributions on meteors presented at this most exciting symposium, and I shall make no attempt to do so. I can better point out trends and possible goals. First a reminiscence. It is more than 30 years ago when I first began seriously to study the problems of meteors. A major expectation then concerned hyperbolic meteor orbits, or meteoroids originating in interstellar space. We knew, of course, that many meteors came from comets and supposed that some of the sporadic meteors came from asteroids. These problems appear now to be largely solved, although the negative results with regard to hyperbolic meteors are definitive only at the 1% level. With our more precise instrumentation and continued observations I would not be too surprised if we might someday find an interstellar meteor. The expectation might be as high as 10−4among observed meteors. The contribution of the asteroid belt, particularly carbonaceous chondrites or whatever similar fragile bodies are indicated by McCrosky's observations of the fireballs, is truly uncertain. Both Ceplecha and Kresák have shown some strong evidence that we cannot discount possible asteroidal contributions among the photographic meteors.