The Soil Moisture Active Passive Validation Experiment 2012, or SMAPVEX12, will use radiometer and radar L-band microwave measurements to study retrieval of land surface soil moisture over vegetation at an agricultural site near Winnipeg, Canada. Knowledge gained from this research will help improve the soil moisture retrieval algorithms to be used for NASA's Soil Moisture Active Passive, or SMAP, satellite mission planned for launch in 2014. Two aircraft will fly in the field campaign during June and July. A NASA G-III will carry the Uninhabited Aerial Vehicle Synthetic Aperture Radar, or UAVSAR, mounted in a pod under the aircraft. The second aircraft, a DHC-6 Twin Otter, will carry the PALS, or Passive Active L- and S-band Sensor, a combined polarimetric radiometer and radar sharing an array antenna.
Follow the progress of the SMAPVEX12 mission here: http://smap.jpl.nasa.gov/blogs/