Bob Grimm - Instruments and Missions

FLIGHT HARDWARE AND MISSION CONCEPT DEVELOPMENT

Low-Frequency Electromagnetic Instrumentation

The Mars EM page describes why low-frequency EM is optimal for groundwater detection and characterization on Mars. Here are some electric- and magnetic-field sensors I've worked on.

* Time-Domain Electromagnetic (TDEM) Sounder. Active EM technique, most commonly using magnetic fields only, that is widely employed in terrestrial groundwater exploration.

* Spin Dependent Tunneling (SDT) Wideband Magnetometer. Recent technology based on magnetoresistance.

* Electric Field Sensors. Low-frequency passive measurements (magnetotellurics) require high sensitivity to natural electromagnetism.

* Capacitively Coupled Induced Polarization (CCIP). Active technique using electric fields only. Shallower depth of investigation for same resources than time-domain EM, but allows complete characterization of electrical properties (complex permittivity / resistivity). Ice (even in the subsurface) has a diagnostic low-frequency permittivity signature. Selected under PIDDP in 2007

Radiofrequency Instrumentation.

Although I've argued that low-frequency EM is the best way to characterize water on Mars, RF is the best way to view crustal structure and stratigraphy at shallower depths. I've led several instrument development efforts here too.

Mission Concepts

for geophysical exploration of Mars and Venus.