| dc.description.abstract | Gravimetry, the measurement of slight variations in gravitational acceleration, can be used to infer density distributions and structures in the crust of a planetary body. The vast majority of studies on bodies other than the Earth have been constrained to orbital surveys, restricting the resolution of the data. Conducting surveys on or near the surface would allow for higher resolution data to be collected and the ability to resolve the finer scale structure of planetary crusts. On Earth, such surveys are conducted using a device known as a gravimeter. Traditional gravimeters are relatively massive, expensive, and fragile which limits their suitability for planetary exploration. In this thesis, a project that supports wider efforts to mature micro-electromechanical systems (MEMS) gravimeters is discussed. NASA has developed an instrument with the goal of using MEMS technology to conduct gravity surveys. The instrument, named HELIX, includes a MEMS inertial measurement unit (IMU) that contains an accelerometer triad – such as those found in most smartphones, though more sensitive. The use of a precision accelerometer triad for gravimetry is referred to as “inertial gravimetry.” The efforts that this project supports aim to 3 develop MEMS accelerometers that are sensitive and stable enough to qualify as gravimeters, which on Earth is the measurement of the solid Earth tides, and then utilize these devices for planetary exploration. Such devices are more robust and have lower mass, cost, and power requirements than traditional gravimeters making them well-suited for extraterrestrial
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