The MAVEN Magnetic Field Investigation

Abstract

The MAVEN magnetic field investigation is part of a comprehensive particles and fields subsystem that will measure the magnetic and electric fields and plasma environment of Mars and its interaction with the solar wind. The magnetic field instrumentation consists of two independent tri-axial fluxgate magnetometer sensors, remotely mounted at the outer extremity of the two solar arrays on small extensions ("boomlets"). The sensors are controlled by independent and functionally identical electronics assemblies that are integrated within the particles and fields subsystem and draw their power from redundant power supplies within that system. Each magnetometer measures the ambient vector magnetic field over a wide dynamic range (to 65,536 nT per axis) with a resolution of 0.008 nT in the most sensitive dynamic range and an accuracy of better than 0.05 %. Both magnetometers sample the ambient magnetic field at an intrinsic sample rate of 32 vector samples per second. Telemetry is transferred from each magnetometer to the particles and fields package once per second and subsequently passed to the spacecraft after some reformatting. The magnetic field data volume may be reduced by averaging and decimation, when necessary to meet telemetry allocations, and application of data compression, utilizing a lossless 8-bit differencing scheme. The MAVEN magnetic field experiment may be reconfigured in flight to meet unanticipated needs and is fully hardware redundant. A spacecraft magnetic control program was implemented to provide a magnetically clean environment for the magnetic sensors and the MAVEN mission plan provides for occasional spacecraft maneuversmultiple rotations about the spacecraft x and z axes-to characterize spacecraft fields and/or instrument offsets in flight.

Vectorized magnetometer for space applications using electrical readout of atomic scale defects in silicon carbide

“…Because the response of the ferromagnetic core is nonlinear, the induced signal will be rich in harmonics which can be used as a reference to null the external field with a third set of coils. Fluxgate magnetometers have flown on an extensive list of missions; some of those worth noting include the two Voyager missions on the Planetary Grand Tour encompassing Jupiter, Saturn, Uranus, Neptune, Pluto, now venturing into interstellar space, the Ulysses mission to study the Sun14, the Cassini mission to Saturn15, the MESSENGER mission to Mercury16, the BepiColombo Mercury Planetary Orbiter17, the MAVEN mission to Mars18, and the Juno mission to Jupiter which arrived on July 4 th 201619. While not the most sensitive option for space bound magnetometers, fluxgate sensors are moderately stable and can exhibit high sensitivity .…”

Longitudinal Properties of a Widespread Solar Energetic Particle Event on 2014 February 25: Evolution of the Associated Cme Shock

“…The three bottom panels of Figure 13 show the magnetic field magnitude and angular orientation in the RTN spacecraft centered coordinate system as observed by the magnetic field investigation onboard Juno (Connerney et al 2013). Based uniquely on the magnetic field data, we see that the passage of a shock at 60/16:39 UT (indicated by the solid vertical line labelled S) was followed by the rotation of the magnetic field suggesting the passage of a magnetic cloud starting at ∼13:50 UT on day 61 and ending at ∼00:25 UT on day 63 (indicated by the vertical dashed lines in Figure 13).…”

MAVEN SupraThermal and Thermal Ion Compostion (STATIC) Instrument

“…These include the Solar Wind Ion Analyzer (SWIA, Halekas et al 2013), the Solar Wind Electron Analyzer (SWEA, and the Langmuir Probe and Wave experiment (LPW, Andersson et al 2015). STATIC data analysis will also utilize observations from the Magnetometer (Connerney et al 2015) for contextual, pickup ion and related wave analysis, and the Solar Energetic Particle experiment (SEP, Larson et al 2015) for determining background from penetrating radiation.…”

“…STATIC observations will also be cross-calibrated with plasma densities determined by SWEA and LPW (Andersson et al 2015). STATIC's inflight calibration data analysis will also utilize observations from the other MAVEN sensors including the Magnetometer (Connerney et al 2015) for pickup ion analysis, and LPW for analyzing ion heating and spacecraft potential.…”