17:15 〜 19:15
[PEM12-P31] The MXD-2 rocket project to study dust in the mesosphere: preparation for analyzing collected samples
キーワード：中間圏、ダスト、ロケット実験、流星塵
The earth's mesosphere is the region where the cosmic dust and meteoroids that constantly enter the atmosphere ablate and re-condense to form nanometer-size dust particles called meteoric smoke particles (MSPs). The MSPs are believed to play an active role in the physical processes of producing several mesospheric phenomena that are observed during the summer months above the middle and polar latitudes, such as noctilucent clouds and polar mesospheric summer echoes. Water ice particles can form at these latitudes during summer because the temperature minimum at the mesopause is lower than during other seasons. The MSPs can enhance the growth of ice particles because they facilitate heterogeneous condensation. However, little is known about the characteristics of MSPs, including their composition and size distribution.
MAXIDUSTY-2 rocket campaign (MXD-2), designed to study the mesospheric dust in relation to cosmic dust and ionospheric conditions, is planned in July 2025 from Andøya Space in Norway. The MXD-2 will conduct in-situ measurements of charged dust and the surrounding plasma components at rocket at altitudes between 70 and 110 km and collect samples of the dust particles. Ground-based observational instruments will support the MXD-2; EISCAT radar measurements will be made during the campaign.
Several model studies, both one-dimensional and two-dimensional simulation, suggested that MSPs were expected to have sizes from a few nanometers and downward, and a more recent study utilizing the data measured by Faraday cup dust detector onboard the MXD-1 and MXD-1B sounding rockets, a predecessor of MXD-2, estimated that the MSPs in the size range from 0.45 to 1.5 nm would have a size distribution that follows a weak inverse power law. However, these results have not reached an uncontroversial conclusion. And there are still a lot of uncertainties, including the material composition.
The sample collection is the most challenging part of the MXD-2 project to enable a direct analysis of mesospheric dust particles that will give us accurate information about the MSPs' properties. The sample particles will be collected on a standard TEM grid.
In preparation for analyzing real sample particles, we examined lab-made Mg-silicate and Mg-Fe-silicate samples produced in the laboratory of the Low-Temperature Science Institute at Hokkaido University, Japan. We investigate the obtained size distributions of particles and their peak position for each sample. In this presentation, we will present an overview of the MXD-2 rocket project and show some provisional results of TEM grid analysis on the laboratory produced samples as a preparation for the coming MXD-2 analysis.
MAXIDUSTY-2 rocket campaign (MXD-2), designed to study the mesospheric dust in relation to cosmic dust and ionospheric conditions, is planned in July 2025 from Andøya Space in Norway. The MXD-2 will conduct in-situ measurements of charged dust and the surrounding plasma components at rocket at altitudes between 70 and 110 km and collect samples of the dust particles. Ground-based observational instruments will support the MXD-2; EISCAT radar measurements will be made during the campaign.
Several model studies, both one-dimensional and two-dimensional simulation, suggested that MSPs were expected to have sizes from a few nanometers and downward, and a more recent study utilizing the data measured by Faraday cup dust detector onboard the MXD-1 and MXD-1B sounding rockets, a predecessor of MXD-2, estimated that the MSPs in the size range from 0.45 to 1.5 nm would have a size distribution that follows a weak inverse power law. However, these results have not reached an uncontroversial conclusion. And there are still a lot of uncertainties, including the material composition.
The sample collection is the most challenging part of the MXD-2 project to enable a direct analysis of mesospheric dust particles that will give us accurate information about the MSPs' properties. The sample particles will be collected on a standard TEM grid.
In preparation for analyzing real sample particles, we examined lab-made Mg-silicate and Mg-Fe-silicate samples produced in the laboratory of the Low-Temperature Science Institute at Hokkaido University, Japan. We investigate the obtained size distributions of particles and their peak position for each sample. In this presentation, we will present an overview of the MXD-2 rocket project and show some provisional results of TEM grid analysis on the laboratory produced samples as a preparation for the coming MXD-2 analysis.