Byron Smiley

Rocket‐borne mesospheric measurement of heavy (m≫10 amu) charge carriers

A rocket-borne probe has been developed to detect charged atmospheric aerosols. The probe is a current collecting surface, shielded by a magnetic field to prevent the detection of electrons and ions below a threshold in mass. During the first test flight above White Sands, New Mexico, a narrow layer of positive charge carriers was detected at an altitude of 86.5 km with vertical extent of ≈500 m, most likely a sudden E-layer related to the deposition of meteoric metal ions. A wide layer of negative charge carriers was observed in the altitude range of 75–86 km, consistent with the density of negative ions in this altitude range.

Rocket probing of PMSE and NLC — Results from the recent MIDAS/MaCWAVE campaign

Abstract From 29 June to 6 July 2002, the European/American MIDAS/MaCWAVE campaign took place at the Andoya Rocket Range (69°N, 16°E) in Norway. Three MMAS payloads were launched in two different salvoes to study the thermal and dynamical environment of Polar Mesosphere Summer Echoes (PMSE) and noctilucent clouds (NLC). All the payloads were equipped with instruments to measure the number density of positive ions, electrons, charged aerosol particles, and neutrals. An electric field experiment was also included aboard one of the MIDAS payloads. An overview of the preliminary results from the campaign will be presented with emphasis on the first salvo where both NLC and PMSE were present. In particular, the small-scale structures measured during passage through these layers will be compared to previous measurements performed in NLC and PMSE conditions.

A Rocket-borne Detector for Charged Atmospheric Aerosols

Publisher Summary Evidence for aerosols in the polar mesosphere includes noctilucent clouds (NLC) and strong radar backscatter called polar mesospheric summer echoes (PMSE). Electrostatic probes collecting electrons find narrow layers (bite-outs) with reduced electron densities which may arise from the attachment of electrons to macroscopic particles. NLC, PMSE, and bite-outs occur at altitudes of 80–90 km and have been observed to occur simultaneously. A rocket-borne charge-collecting probe has been developed to detect charged atmospheric aerosols. A magnetic field is used to prevent detection of electrons and low-mass ions. Work on this topic is continuing in several directions. Computations are being made of the flow field around the rocket for the conditions of our test flight. The goals are to find the effect of shock heating on the evaporation rate of ice clusters, and the effect of both flow and evaporation upon the detection efficiency.