| Popis: |
Measurements of the flux of picogram dust particles in selenocentric, cislunar, and interplanetary space between 1.0 and 1.6 AU were made by cosmic dust experiments on Lunar Explorer 35 (LE35), Lunar Orbiters (LO), HEOS, Mariner IV (MIV) and Pioneers 8/9 between 1964 and 1974. The cumulative flux-mass distribution (CFMD) as a function of heliocentric range was determined from MIV data, and the CFMD in selenocentric space was determined by analysis of LE35 data. Evidence of lunar ejecta from impacts of interplanetary dust particles was found in the LE35 data. Results of recent laboratory studies of hypervelocity impact of micron-size simulated cosmic dust indicate that a major portion of the lunar ejecta escapes the earth-moon system and dwells in a very limited volume of heliocentric space that is symetrical with the ecliptic plane. The recent Gegenschein measurements eeported by Roosen show a maximum intensity in the ecliptic plane, but the intensity distribution is asymmetric. The possible relation of these observations to cosmic dust measurements is discussed. |
