Instrument Information
IDENTIFIER urn:esa:psa:context:instrument:juice.radem::1.0
NAME RADEM
TYPE
DESCRIPTION The BepiColombo mission is designed to orbit Mercury after one swingby at planet Earth and two swingbys at Venus. It has been launched on October 20, 2018 in Kourou, French Guayana and will use the swingbys to slow down and reach Mercury first in October 2021. During the long cruise phase, MPO-MAG will contribute to studies of solar wind turbulence and transient phenomena. The magnetic field data collected during the Earth swingby have been used to improve the calibration and to fine tune the instrument SPICE frame kernels. The magnetic field observation at Venus will augment the knowledge of the Venus magnetosphere. Stable orbits around Mercury can be flown from 2025 onwards after lots of complex manoeuvres, the separation of the Mercury Planetary Orbiter (MPO), the Mercury Transfer Module (MTM), and the Mercury Magnetospheric Orbiter (MMO, so called MIO). MPO will be injected into an initial 480 km ×1500 km polar orbit around Mercury with a 2.3h orbital period. At Mercury, we will conduct a global mapping of the planetary magnetic field, determine the dynamo generated field and investigate the secular variation. Furthermore, the study of induced magnetic fields and field-aligned currents will help to reveal the interior structure in concert with other geophysical instruments. The orbit is also well-suited to study dynamical phenomena at the Hermean magnetopause and magnetospheric cusps. Together with its sister instrument the MIO-MGF on-board the MIO spacecraft, the magnetometers at Mercury will investigate the reaction of the highly dynamic magnetosphere to changes in the solar wind. The magnetometer instrument MPO-MAG on-board the MPO spacecraft has been provided by the Institute for Geophysics and extraterrestrial Physics at the Technische Universitaet Braunschweig, Germany under lead of the PI Daniel Heyner. The instrument comprises two tri-axial fluxgate magnetometers mounted on a 2.9 m boom and are 0.8 m apart. They observe the magnetic field with vector rates of up to 128 Hz at a maximum range of +-2048 nT. For the sake of a flexible adaption to occurring telemetry (TM) restrictions the vector rate can be set to 0.5 Hz, 1 Hz, 2 Hz, 4 Hz, 16 Hz, 32 Hz, 64 Hz, and 128 Hz. For an optimal adaption to the ambient magnetic field the instrument can be operated in the following ranges (+-): 8 nT, 16 nT, 32 nT, 64 nT, 128 nT, 256 nT, 1024 nT, 2048 nT. Furthermore the data can be compressed before the downlink in order to shrink the transmitted TM volume. A special feature is the so called Selective Downlink (S/D) mode minimizing the downlink TM volume drastically. Here, the instrument is operated at full data rate and stores the high resolution data in an onboard ring buffer, but does not send them down. Only a low sampled data stream is generated in parallel and instantaneously transmitted to Earth, where the data are analysed in order to detect special features. According to a possibly detected event the transmission of a limited set of high resolution data from the buffer will be triggered. For maintenance purposes the instrument is equipped with several calibration and special modes. The magnetometer is a fully digital instrument, where the magnetic field signal measured by the sensor is amplified and immediately converted into its digital equivalent, which acts as input to an FPGA. This device generates a dynamic digital feedback signal, which is converted into an analogue feedback signal and connected to the sensor?s feedback coil. Additionally the FPGA generates the excitation signal that is conditioned by the drive electronics before injection to the excitation coil. On the other side, the FPGA is connected to the Instrument Controller, which collects the magnetic field data and controls the magnetometer. Besides the science data of both sensors also housekeeping data (HK) is generated for a proper surveillance of the instrument. The science data are made available to the public via the Planetary Science Archive (PSA) hosted by ESA and the Planetary Data System (PDS) operated by NASA. Data are provided at different processing levels (raw, calibrated, derived) and various convenient coordinate systems (unit reference frame: URF, s/c-frame: SCF, celestial coordinates like e.g. ECLIPJ2000: E2K). The data are PDS4 compliant and organized by calibration level, mission phases, sensor, coordinate system, and measurement rate. They are clustered in files on daily basis. Although MPO-MAG is located on a boom, spacecraft magnetic disturbance fields have a high impact on the magnetic field observations. The disturbances are manifold. They are present at DC as well as on AC level and are caused by varying s/c currents, thruster and reaction wheel operations due to AOCS needs, P/L activities and possibly other sources. All these disturbances are subject to advanced data cleaning procedures under permanent improvements. We hold the calibration dear for the maximization of the resolution and the S/N ratio of the expected tiny magnetic signatures in order to reveal more secrets of Mercury's interior structure. Finally a general warning is stated here: * Use the data with caution and analytic expertise. * Please read the provided documentation carefully. * In any doubt of the "realness" of a detected structure please contact the PI team for clarification. The MPOMAG instrument is described in full detail in [HEYNERETAL2020]. The Experiment to Archive Interface Control Document [RICHTERTAL2020] is part of current the dataset. The Experiment User Manual [FISCHERETAL2017] is also part of this dataset.
MODEL IDENTIFIER
NAIF INSTRUMENT IDENTIFIER
SERIAL NUMBER not applicable
REFERENCES Heyner D., H.-U. Auster, K.-H. Fornacon, C. Carr, I. Richter, J. Z. D. Mieth, P. Kolhey, W. Exner, U. Motschmann, W. Baumjohann, A. Matsuoka,W . Magnes, G. Berghofer, D. Fischer, F. Plaschke, R. Nakamura, Y. Narita, M. Delva, M. Volwerk, A. Balogh, M. Dougherty, T. Horbury, B. Langlais, M. Mandea, A. Masters, J. S. Oliveira, B. Sanchez-Cano, J. A. Slavin, S. Vennerstroem, J. Vogt, J. Wicht, and K.-H. Glassmeier; The BepiColombo Planetary Magnetometer MPO-MAG: What can we Learn From the Hermean Magnetic Field?, Space Science Reviews, submitted 2020.

Richter I., S. Martinez, D.Heyner, MPO-MAG-Team; MPO-MAG Experiment-to-Archive ICD (EAICD); BC-MAG_ICD-001, ESA,2020

Fischer D., G. Berhofer; MERMAG Instrument User Manual; BC-MAG_UM-0002, IWF, 2017