Mars Observer magnetic fields investigation

Abstract

The Mars Observer magnetic fields investigation will provide fast vector measurements of the Martian magnetic field over a wide dynamic range. The fundamental objectives of this investigation are (1) to establish the nature of the magnetic field of Mars, (2) to develop appropriate models for its representation, which take into account the internal sources of magnetism and the effects of the interaction with the solar wind, and (3) to map the Martian crustal remanent field to a resolution consistent with the Mars Observer orbit altitude and ground track separation. The basic instrumentation complement implemented for this mission is a synergistic combination of a dual, triaxial, flux gate magnetometer system and an electron reflectometer with sensors mounted on a spacecraft boom. The dual magnetometer system allows the real‐time estimation and correction of spacecraft‐generated fields, while the electron reflectometer provides remote magnetic field sensing capabilities. These instruments have an extensive spaceflight heritage, and similar versions of the same have been flown in numerous missions like Voyager, Magsat, International Solar Polar mission (ISPM), Giotto, Active Magnetospheric Particle Tracer Explorers, and Global Geospace Science (GGS). Depending on the telemetry rate supported, a minimum of 2–16 vector samples per second will be acquired. The instrument is microprocessor controlled, can be partially reprogrammed in flight, and supports the packet telemetry protocol implemented for Mars Observer.

Simulated solar wind plasma interaction with the Martian exosphere: influence of the solar EUV flux on the bow shock and the magnetic pile-up boundary

“…Therefore this interaction is similar in many ways to that of Venus or comets (Acuña et al, 1998). The MGS measurements have provided us a clear identification of the boundaries such as the bow shock (BS) and the magnetic pile-up boundary (MPB), located downstream the bow shock and upstream the ionopause.…”

“…Due to the absence of a global magnetic field of the internal origin (Acuña et al, 1998), the upper atmosphere and the dayside ionosphere interact directly with the solar wind plasma. The Magnetometer/Electron reflectometer (MAG/ER) experiment on board Mars Global Surveyor (MGS) spacecraft has revealed the presence of crustal magnetic fields ).…”

Dependence of the location of the Martian magnetic lobes on the interplanetary magnetic field direction: Observations from Mars Global Surveyor

“…Among other important results, the measurements made by the magnetometer (MAG) on board the Mars Global Surveyor (MGS) spacecraft [Acuña et al, 1992] showed that Mars does not have a significant intrinsic magnetic field [Acuña et al, 1998]. As a consequence, there is a direct interaction between the magnetized solar wind (SW) and the atmosphere/ionosphere of the planet.…”

Mars MOURA magnetometer demonstration for high-resolution mapping on terrestrial analogues

“…Mars' magnetic field has been exhaustively measured between 100 and 440 km altitude by Mars Global Surveyor (Acuña et al, 1998;Connerney et al, 2005;Morschhauser et al, 2014). These data show that the magnetic anomalies of the martian crust are up to 20 times higher than those of the Earth (Scott and Fuller, 2004).…”

“…A second objective is the magnetic investigation of these sites and their implication as terrestrial analogues of Mars. A further objective is the potential of high-resolution mapping to show the lowest magnetic contrasts in the terrain and their correlation with the distinct magnetic carriers responsible for their signatures (Acuña et al, 1998;Connerney et al, 2005;.…”