Magnetic Anomaly Analysis to Determine Parameter Space for a Magnetometer Instrument Onboard a Mars Scout, 20-R9609Printer Friendly Version
Inclusive Dates: 03/02/06 07/02/06
Background - Investigation of the crustal magnetization of Mars is considered a fundamental objective in understanding the evolution of the planet's surface and interior. The discovery of strong magnetic anomalies in the southern highlands of Mars was a major achievement of the Mars Global Surveyor mission. The data from this mission, gathered from altitudes of approximately 100 400 km, were used to compile global, low-resolution magnetic anomaly maps of Mars. There is considerable debate in the scientific community regarding the shape and spatial extent of the sources of the magnetic anomalies and their modeled magnetization vectors. Observing the magnetic anomaly data on Mars from aerial platforms such as a balloon at altitudes of less than 10 km could potentially constrain the uncertainties associated with the source characteristics of Martian magnetic anomalies. This research explored different scenarios of magnetic anomaly sources and their characteristics from a balloon platform on Mars at altitudes of less than 10 km.
Approach - We developed alternative scenarios with small multiple sources for known magnetic anomalies on Mars that were previously modeled as uniformly magnetized bulk sources. Forward modeling of the anomalies from observations at altitudes of less than 10 km could distinguish between the different scenarios. We also evaluated grid versus single-pass magnetic data acquisition by a magnetometer from a balloon platform on Mars by comparing inversion results from these two data sources.
Accomplishments - We noted that the accuracy of the inversion depended largely on the initial estimates of the starting source parameters. The accuracy generally deteriorated with increasing numbers of inversion variables for both grid and profile data. In spite of these limitations, magnetic anomaly profiles acquired at altitudes of less than 10 km along random balloon trajectories could resolve shallow and deep sources based on anomaly wavelength. The low-altitude profiles have the potential to reveal high amplitude and relatively short wavelength anomalies that would indicate multiple sources or larger, more uniform anomalies characteristic of a single bulk source. Results from this quick-look study supported proposal development for the Mars Scout Mission Announcement of Opportunity for 2011. Preparations are underway to present the results from this research at the 2007 Lunar and Planetary Science Conference.