Author
Konrad Schwingenschuh
Other affiliations: Institut für Weltraumforschung (Space Research Institute)
Bio: Konrad Schwingenschuh is an academic researcher from Austrian Academy of Sciences. The author has contributed to research in topics: Solar wind & Magnetosphere. The author has an hindex of 38, co-authored 211 publications receiving 6817 citations. Previous affiliations of Konrad Schwingenschuh include Institut für Weltraumforschung (Space Research Institute).
Papers published on a yearly basis
Papers
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TL;DR: In this paper, the authors present an overview of the instrumentation used to measure the magnetic field on the four Cluster spacecraft and an overview the performance of the operational modes used in flight.
Abstract: . The accurate measurement of the magnetic field along the orbits of the four Cluster spacecraft is a primary objective of the mission. The magnetic field is a key constituent of the plasma in and around the magnetosphere, and it plays an active role in all physical processes that define the structure and dynamics of magnetospheric phenomena on all scales. With the four-point measurements on Cluster, it has become possible to study the three-dimensional aspects of space plasma phenomena on scales commeasurable with the size of the spacecraft constellation, and to distinguish temporal and spatial dependences of small-scale processes. We present an overview of the instrumentation used to measure the magnetic field on the four Cluster spacecraft and an overview the performance of the operational modes used in flight. We also report on the results of the preliminary in-orbit calibration of the magnetometers; these results show that all components of the magnetic field are measured with an accuracy approaching 0.1 nT. Further data analysis is expected to bring an even more accurate determination of the calibration parameters. Several examples of the capabilities of the investigation are presented from the commissioning phase of the mission, and from the different regions visited by the spacecraft to date: the tail current sheet, the dusk side magnetopause and magnetosheath, the bow shock and the cusp. We also describe the data processing flow and the implementation of data distribution to other Cluster investigations and to the scientific community in general. Key words. Interplanetary physics (instruments and techniques) – magnetospheric physics (magnetospheric configuration and dynamics) – space plasma physics (shock waves)
1,218 citations
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Janssen Pharmaceutica1, University of Padua2, Open University3, Tel Aviv University4, Ames Research Center5, European Space Agency6, Agenzia Spaziale Italiana7, Centre national de la recherche scientifique8, Finnish Meteorological Institute9, Austrian Academy of Sciences10, Spanish National Research Council11, University of Murcia12, University of Cologne13, University of Catania14, Polytechnic University of Milan15, Boston University16
TL;DR: The temperature and density profiles, as determined by the Huygens Atmospheric Structure Instrument (HASI), from an altitude of 1,400 km down to the surface were higher than expected and the extent of atmospheric electricity was also hitherto unknown.
Abstract: On the basis of previous ground-based and fly-by information, we knew that Titan's atmosphere was mainly nitrogen, with some methane, but its temperature and pressure profiles were poorly constrained because of uncertainties in the detailed composition. The extent of atmospheric electricity (‘lightning’) was also hitherto unknown. Here we report the temperature and density profiles, as determined by the Huygens Atmospheric Structure Instrument (HASI), from an altitude of 1,400 km down to the surface. In the upper part of the atmosphere, the temperature and density were both higher than expected. There is a lower ionospheric layer between 140 km and 40 km, with electrical conductivity peaking near 60 km. We may also have seen the signature of lightning. At the surface, the temperature was 93.65 ± 0.25 K, and the pressure was 1,467 ± 1 hPa.
643 citations
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TL;DR: The Cluster mission as mentioned in this paper provides a new opportunity to study plasma processes and structures in the near-Earth plasma environment using four-point measurements of the magnetic field, which can enable the analysis of the three dimensional structure and dynamics of a range of phenomena which shape the macroscopic properties of the magnetosphere.
Abstract: The Cluster mission provides a new opportunity to study plasma processes and structures in the near-Earth plasma environment Four-point measurements of the magnetic field will enable the analysis of the three dimensional structure and dynamics of a range of phenomena which shape the macroscopic properties of the magnetosphere Difference measurements of the magnetic field data will be combined to derive a range of parameters, such as the current density vector, wave vectors, and discontinuity normals and curvatures, using classical time series analysis techniques iteratively with physical models and simulation of the phenomena encountered along the Cluster orbit The control and understanding of error sources which affect the four-point measurements are integral parts of the analysis techniques to be used The flight instrumentation consists of two, tri-axial fluxgate magnetometers and an on-board data-processing unit on each spacecraft, built using a highly fault-tolerant architecture High vector sample rates (up to 67 vectors s-1) at high resolution (up to 8 pT) are combined with on-board event detection software and a burst memory to capture the signature of a range of dynamic phenomena Data-processing plans are designed to ensure rapid dissemination of magnetic-field data to underpin the collaborative analysis of magnetospheric phenomena encountered by Cluster
373 citations
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Austrian Academy of Sciences1, Chinese Academy of Sciences2, Braunschweig University of Technology3, Imperial College London4, University of California, Los Angeles5, Swedish Institute of Space Physics6, University of Sheffield7, Slovak Academy of Sciences8, European Space Research and Technology Centre9
TL;DR: In this article, the authors compare the magnetic field experiment of the upcoming Venus Express mission with the long lasting Pioneer Venus Orbiter (PVO) observations with respect to the solar wind interaction with Venus.
250 citations
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TL;DR: In this article, the magnetic fields of Mars have been measured from Phobos 2 with high temporal resolution in the tail and down to an 850 km altitude during four successive highly elliptical orbits, the position of the bow shock as well as that of a transition layer, the 'planetopause', were identified.
Abstract: The magnetic fields of Mars have been measured from Phobos 2 with high temporal resolution in the tail and down to an 850-km altitude. During four successive highly elliptical orbits, the position of the bow shock as well as that of a transition layer, the 'planetopause', were identified. Subsequent circular orbits at 6000-km altitude provided the first high-resolution data in the planetary tail and indicate that the interplanetary magnetic field mainly controls the magnetic tail. Magnetic turbulence was also detected when the spacecraft crossed the orbit of Phobos, indicating the possible existence of a torus near the orbit of this moon.
246 citations
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TL;DR: In this paper, the authors present an overview of the instrumentation used to measure the magnetic field on the four Cluster spacecraft and an overview the performance of the operational modes used in flight.
Abstract: . The accurate measurement of the magnetic field along the orbits of the four Cluster spacecraft is a primary objective of the mission. The magnetic field is a key constituent of the plasma in and around the magnetosphere, and it plays an active role in all physical processes that define the structure and dynamics of magnetospheric phenomena on all scales. With the four-point measurements on Cluster, it has become possible to study the three-dimensional aspects of space plasma phenomena on scales commeasurable with the size of the spacecraft constellation, and to distinguish temporal and spatial dependences of small-scale processes. We present an overview of the instrumentation used to measure the magnetic field on the four Cluster spacecraft and an overview the performance of the operational modes used in flight. We also report on the results of the preliminary in-orbit calibration of the magnetometers; these results show that all components of the magnetic field are measured with an accuracy approaching 0.1 nT. Further data analysis is expected to bring an even more accurate determination of the calibration parameters. Several examples of the capabilities of the investigation are presented from the commissioning phase of the mission, and from the different regions visited by the spacecraft to date: the tail current sheet, the dusk side magnetopause and magnetosheath, the bow shock and the cusp. We also describe the data processing flow and the implementation of data distribution to other Cluster investigations and to the scientific community in general. Key words. Interplanetary physics (instruments and techniques) – magnetospheric physics (magnetospheric configuration and dynamics) – space plasma physics (shock waves)
1,218 citations
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TL;DR: The THEMIS Fluxgate Magnetometer (FGM) as discussed by the authors was designed to study abrupt reconfigurations of the Earth's magnetosphere during the substorm onset phase and is capable of detecting variations of the magnetic field with amplitudes of 0.01 nT.
Abstract: The THEMIS Fluxgate Magnetometer (FGM) measures the background magnetic field and its low frequency fluctuations (up to 64 Hz) in the near-Earth space. The FGM is capable of detecting variations of the magnetic field with amplitudes of 0.01 nT, and it is particularly designed to study abrupt reconfigurations of the Earth’s magnetosphere during the substorm onset phase. The FGM uses an updated technology developed in Germany that digitizes the sensor signals directly and replaces the analog hardware by software. Use of the digital fluxgate technology results in lower mass of the instrument and improved robustness. The present paper gives a description of the FGM experimental design and the data products, the extended calibration tests made before spacecraft launch, and first results of its magnetic field measurements during the first half year in space. It is also shown that the FGM on board the five THEMIS spacecraft well meets and even exceeds the required conditions of the stability and the resolution for the magnetometer.
1,198 citations
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TL;DR: To achieve mission objectives, the calibration determined on the ground will be refined in space to ensure all eight magnetometers are precisely inter-calibrated, and the information flow that provides the data on the rapid time scale needed for mission success is described.
Abstract: The success of the Magnetospheric Multiscale mission depends on the accurate measurement of the magnetic field on all four spacecraft. To ensure this success, two independently designed and built fluxgate magnetometers were developed, avoiding single-point failures. The magnetometers were dubbed the digital fluxgate (DFG), which uses an ASIC implementation and was supplied by the Space Research Institute of the Austrian Academy of Sciences and the analogue magnetometer (AFG) with a more traditional circuit board design supplied by the University of California, Los Angeles. A stringent magnetic cleanliness program was executed under the supervision of the Johns Hopkins University’s Applied Physics Laboratory. To achieve mission objectives, the calibration determined on the ground will be refined in space to ensure all eight magnetometers are precisely inter-calibrated. Near real-time data plays a key role in the transmission of high-resolution observations stored on board so rapid processing of the low-resolution data is required. This article describes these instruments, the magnetic cleanliness program, and the instrument pre-launch calibrations, the planned in-flight calibration program, and the information flow that provides the data on the rapid time scale needed for mission success.
977 citations
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TL;DR: Vector magnetic field observations of the martian crust were acquired by the Mars Global Surveyor (MGS) magnetic field experiment/electron reflectometer (MAG/ER) during the aerobraking and science phasing orbits, at altitudes between approximately 100 and 200 kilometers.
Abstract: Vector magnetic field observations of the martian crust were acquired by the Mars Global Surveyor (MGS) magnetic field experiment/electron reflectometer (MAG/ER) during the aerobraking and science phasing orbits, at altitudes between ∼100 and 200 kilometers. Magnetic field sources of multiple scales, strength, and geometry were observed. There is a correlation between the location of the sources and the ancient cratered terrain of the martian highlands. The absence of crustal magnetism near large impact basins such as Hellas and Argyre implies cessation of internal dynamo action during the early Naochian epoch (∼4 billion years ago). Sources with equivalent magnetic moments as large as 1.3 × 1017 ampere-meter2in the Terra Sirenum region contribute to the development of an asymmetrical, time-variable obstacle to solar wind flow around Mars.
966 citations
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TL;DR: The magnetometer and electron reflectometer investigation on the Mars Global Surveyor spacecraft has obtained magnetic field and plasma observations throughout the near-Mars environment, but here the discovery of multiple magnetic anomalies of small spatial scale in the crust of Mars is reported.
Abstract: The magnetometer and electron reflectometer investigation (MAG/ER) on the Mars Global Surveyor spacecraft has obtained magnetic field and plasma observations throughout the near-Mars environment, from beyond the influence of Mars to just above the surface (at an altitude of approximately 100 kilometers). The solar wind interaction with Mars is in many ways similar to that at Venus and at an active comet, that is, primarily an ionospheric-atmospheric interaction. No significant planetary magnetic field of global scale has been detected to date (<2 x 10(21) Gauss-cubic centimeter), but here the discovery of multiple magnetic anomalies of small spatial scale in the crust of Mars is reported.
694 citations