HR: 12:05h
AN: SA22A-08    [Abstracts]
TI: The Nature of Icy Dust Particles in the Polar Summer Mesosphere From Rocket Measurements During DROPPS
AU: Goldberg, R A
EM: Richard.A.Goldberg@nasa.gov
AF: NASA/GSFC, Code 612.3, Greenbelt, MD 20771 United States
AU: * Webb, P A
EM: Phillip.A.Webb.1@gsfc.nasa.gov
AF: UMBC/GEST, Code 612.3 NASA/GSFC, Greenbelt, MD 20771 United States
AU: Pesnell, W D
EM: William.D.Pesnell@nasa.gov
AF: NASA/GSFC, Code 612.1, Greenbelt, MD 20771 United States
AU: Voss, H D
EM: hnvoss@tayloru.edu
AF: Taylor University, 236 W. Reade Ave. Physics Department, Upland, IN 46989 United States
AB: The two Black Brant payloads flown during the DROPPS (Distribution and Role of Particles in the Polar Summer Mesosphere) rocket program were launched during early July, 1999 from Andoya Rocket Range (ARR), Norway. Both payloads included front mounted side by side Particle Impact Detector (PID) charge and mass telescopes. Computer simulations have shown that the PID telescopes have the potential to detect atmospheric ice particles within the mesosphere, having dimensions of a few nanometers. Ice particles of nanometer size are believed to be responsible for polar mesospheric summer echoes (PMSEs), such as those observed at an altitude of ~82-87 km over Andoya during the first DROPPS launch sequence. We have previously presented results from the longer PID charge telescope that indicated two possible particle distributions differing by mean particle size. Due to the different geometries of the PID telescopes (primarily, that the charge telescope is longer than the mass telescope) each PID telescope collects a different portion of the nanometer sized PMSE particles distribution. When compared to the previous PID charge telescope results, the PID mass telescope results allow the true PMSE particle size distribution to be estimated. This talk will introduce the new observations from the shorter PID mass telescope and the comparison to the previous PID charge telescope. By then comparing PID observations with the computer simulations provides information concerning the properties of the PMSE particles, including their "rocky" core size, ice mantle thickness and distribution.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0320 Cloud physics and chemistry
DE: 0340 Middle atmosphere: composition and chemistry
DE: 0394 Instruments and techniques
SC: SPA-Aeronomy [SA]
MN: Fall Meeting 2005