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Keywords = VLF direction finder

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11 pages, 1757 KB  
Article
High-Altitude Discharges and Whistlers of Volcanic Thunderstorms
by Evgeniy I. Malkin, Boris M. Shevtsov, Nina V. Cherneva, Evgeniy A. Kazakov and János Lichtenberger
Atmosphere 2024, 15(12), 1503; https://doi.org/10.3390/atmos15121503 - 17 Dec 2024
Cited by 2 | Viewed by 1391
Abstract
The results of the observations of atmospherics and whistlers initiated by high-altitude electrical discharges that occurred during the eruption of the Kamchatka volcanoes (Bezymianny and Shiveluch (Russia)) on 7 and 10 April 2023 are presented. Recording of atmospherics and associated whistlers was carried [...] Read more.
The results of the observations of atmospherics and whistlers initiated by high-altitude electrical discharges that occurred during the eruption of the Kamchatka volcanoes (Bezymianny and Shiveluch (Russia)) on 7 and 10 April 2023 are presented. Recording of atmospherics and associated whistlers was carried out by a VLF (very low frequencies) radio direction finder. Two-hop whistlers were identified by dispersion coefficient, which corresponded to the double passage of the signal from Kamchatka to Australia and back. The heights of the electric discharges were determined by means of interferograms of direct and reflected from the ionosphere radiofrequency atmospherics. The high-altitude distribution of an electric discharge is obtained, the penetration of which into the ionosphere is responsible for the generation of whistlers. The characteristics of volcanic electrical discharges and whistlers can be used to estimate the height of an explosive eruption. Full article
(This article belongs to the Special Issue Atmospheric Electricity (2nd Edition))
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13 pages, 3120 KB  
Communication
Direct In-Situ Capture, Separation and Visualization of Biological Particles with Fluid-Screen in the Context of Venus Life Finder Mission Concept Study
by Robert E. Weber, Janusz J. Petkowski and Monika U. Weber
Aerospace 2022, 9(11), 692; https://doi.org/10.3390/aerospace9110692 - 6 Nov 2022
Cited by 4 | Viewed by 2614
Abstract
Evidence of chemical disequilibria and other anomalous observations in the Venusian atmosphere motivate the search for life within the planet’s temperate clouds. To find signs of a Venusian aerial biosphere, a dedicated astrobiological space mission is required. Venus Life Finder (VLF) missions encompass [...] Read more.
Evidence of chemical disequilibria and other anomalous observations in the Venusian atmosphere motivate the search for life within the planet’s temperate clouds. To find signs of a Venusian aerial biosphere, a dedicated astrobiological space mission is required. Venus Life Finder (VLF) missions encompass unique mission concepts with specialized instruments to search for habitability indicators, biosignatures and even life itself. A key in the search for life is direct capture, concentration and visualization of particles of biological potential. Here, we present a short overview of Fluid-Screen (FS) technology, a recent advancement in the dielectrophoretic (DEP) microbial particle capture, concentration and separation. Fluid-Screen is capable of capturing and separating biochemically diverse particles, including multicellular molds, eukaryotic cells, different species of bacteria and even viruses, based on particle dielectric properties. In this short communication, we discuss the possible implementation of Fluid-Screen in the context of the Venus Life Finder (VLF) missions, emphasizing the unique science output of the Fluid-Screen instrument. FS can be coupled with other highly sophisticated instruments such as an autofluorescence microscope or a laser desorption mass spectrometer (LDMS). We discuss possible configurations of Fluid-Screen that upon modification and testing, could be adapted for Venus. We discuss the unique science output of the Fluid-Screen technology that can capture biological particles in their native state and hold them in the focal plane of the microscope for the direct imaging of the captured material. We discuss the challenges for the proposed method posed by the concentrated sulfuric acid environment of Venus’ clouds. While Venus’ clouds are a particularly challenging environment, other bodies of the solar system, e.g., with liquid water present, might be especially suitable for Fluid-Screen application. Full article
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9 pages, 1251 KB  
Communication
Venus Life Finder Missions Motivation and Summary
by Sara Seager, Janusz J. Petkowski, Christopher E. Carr, David H. Grinspoon, Bethany L. Ehlmann, Sarag J. Saikia, Rachana Agrawal, Weston P. Buchanan, Monika U. Weber, Richard French, Pete Klupar, Simon P. Worden, Darrel Baumgardner and on behalf of the Venus Life Finder Mission Team
Aerospace 2022, 9(7), 385; https://doi.org/10.3390/aerospace9070385 - 18 Jul 2022
Cited by 30 | Viewed by 13704
Abstract
Finding evidence of extraterrestrial life would be one of the most profound scientific discoveries ever made, advancing humanity into a new epoch of cosmic awareness. The Venus Life Finder (VLF) missions feature a series of three direct atmospheric probes designed to assess the [...] Read more.
Finding evidence of extraterrestrial life would be one of the most profound scientific discoveries ever made, advancing humanity into a new epoch of cosmic awareness. The Venus Life Finder (VLF) missions feature a series of three direct atmospheric probes designed to assess the habitability of the Venusian clouds and search for signs of life and life itself. The VLF missions are an astrobiology-focused set of missions, and the first two out of three can be launched quickly and at a relatively low cost. The mission concepts come out of an 18-month study by an MIT-led worldwide consortium. Full article
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