Dust Particles of Micron Size Associated with the Leonid Meteor Stream.

Abstract

view Abstract Citations References Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Dust Particles of Micron Size Associated with the Leonid Meteor Stream. Alexander, W. M. ; McCracken, C. W. ; Lagow, H. E. Abstract Data from the acoustic system mounted on the satellite, 1959~ (Vanguard III), for registering impacts of interplanetary dust particles on the satellite show a particularly high level of activity during the 16-17 November Leonid meteor shower. Approximately 2800 impacts of particles with momenta greater than 1 X 10-2 dyne sec occurred within a 70-hour interval. The limiting mass sensitivity of the detector for particles of the Leon id stream was 1.3X10-9 g. Two of the sampling intervals contained impact rates of about 7 times the average impact rate for the 70-hr interval. One pass of 6rn+20S duration contained 200+10 impacts, giving a impact rate of 50 times the average rate. In contrast, one sampling interval of 2.3-hour duration contained no impacts. A histogram of the impact rate reveals large variations in the impact rate, implying that there is considerable fine structure in the stream. The presence in the meteor stream of particles of the sizes measured and the fluctuations in the impact rate of such particles are of considerable interest in the study of comet and meteor-stream evolution. Since dynamical perturbations and the Poynting-Robertson effect will tend to rapidly disperse concentrations of small dust particles, the association of such concentrations with a meteor stream suggests a rather recent origin for the observed particles. The possibility of observing dust particles in the micron-size range within particular meteor streams is discussed on the basis of known characteristics of the streams. Publication: The Astronomical Journal Pub Date: March 1961 DOI: 10.1086/108571 Bibcode: 1961AJ.....66S.277A full text sources ADS |