11:00 〜 13:00
[PEM10-P18] Geomagnetic field measurement with Magneto-Impedance Magnetometer (MIM) onboard Loss through Auroral Microburst Pulsations (LAMP) sounding rocket
Magneto-impedance (MI) effect, which was discovered about 30 years ago, is that the impedance of an amorphous wire sensitively changes as a function of an external magnetic field when a high-frequency current is applied through the wire as a carrier. A micro-size magnetic sensor that utilizes this effect becomes commercially available. We made some modifications to the commercially available MI sensors as they can cover the range of the geomagnetic field. For the period of March 30 to April 27, 2018, we conducted experimental observations of geomagnetic field variations with the modified MI sensors at Mineyama ground observation site, which is located about 100 km north-west of Kyoto. Data obtained with the modified MI sensors were compared with those from the fluxgate magnetometer that has been working at the site. Results showed that the modified MI sensor recorded geomagnetic variations with amplitudes of ~1 nT that were also detected with the fluxgate magnetometer. This suggests that MI sensors are useful for researches in geomagnetism or space physics, although they are much less expensive than fluxgate magnetometers.
For an experimental performance test of MI sensors on sounding rockets, we have been developing a triaxial magnetometer using the modified MI sensors (Magneto-Impedance Magnetometer, MIM) since autumn 2018. MIM is composed of the sensor component (MIM-S) and the data processing electronics component (MIM-E). MIM-S measures the geomagnetic field in the range of ±80,000 nT with a sampling frequency of 200 Hz and has the noise level of approximately 50 pT/√Hz. The dimensions, mass, and power consumption of MIM-S are as small as 70 mm by 70 mm by 50 mm, <0.5 kg, and ~3 W, respectively. MIM-E digitizes the output from MIM-S with a 24-bit A/D converter, resulting in a nominal resolution is ~10 pT, and processes the data with a Raspberry Pi3. Its dimensions, mass, and power consumption are 150 mm by 150 mm by 44 mm, ~1.3 kg, and ~6 W, respectively. We have conducted a thermal vacuum test, a vibration test, and an orthogonality and sensitivity calibration of MIM, and provided it with the Loss through Auroral Microburst Pulsations (LAMP) sounding rocket, which will be launched from Poker Flat Research Range, Alaska at altitude of ~400 km in February 2022. MIM contributes to the LAMP mission by measuring the geomagnetic field variations in the ionosphere during pulsating aurora. This is the first mission that delivers magneto-impedance sensors at the ionospheric altitude by a sounding rocket. In presentation, we will display observation data from LAMP/MIM and discuss future possibility of MI sensors as magnetometers for sounding rockets or microsatellites.
For an experimental performance test of MI sensors on sounding rockets, we have been developing a triaxial magnetometer using the modified MI sensors (Magneto-Impedance Magnetometer, MIM) since autumn 2018. MIM is composed of the sensor component (MIM-S) and the data processing electronics component (MIM-E). MIM-S measures the geomagnetic field in the range of ±80,000 nT with a sampling frequency of 200 Hz and has the noise level of approximately 50 pT/√Hz. The dimensions, mass, and power consumption of MIM-S are as small as 70 mm by 70 mm by 50 mm, <0.5 kg, and ~3 W, respectively. MIM-E digitizes the output from MIM-S with a 24-bit A/D converter, resulting in a nominal resolution is ~10 pT, and processes the data with a Raspberry Pi3. Its dimensions, mass, and power consumption are 150 mm by 150 mm by 44 mm, ~1.3 kg, and ~6 W, respectively. We have conducted a thermal vacuum test, a vibration test, and an orthogonality and sensitivity calibration of MIM, and provided it with the Loss through Auroral Microburst Pulsations (LAMP) sounding rocket, which will be launched from Poker Flat Research Range, Alaska at altitude of ~400 km in February 2022. MIM contributes to the LAMP mission by measuring the geomagnetic field variations in the ionosphere during pulsating aurora. This is the first mission that delivers magneto-impedance sensors at the ionospheric altitude by a sounding rocket. In presentation, we will display observation data from LAMP/MIM and discuss future possibility of MI sensors as magnetometers for sounding rockets or microsatellites.