This ground-level photo of the Halema'uma'u Crater of the Kilauea volcano was taken by a member of the NASA JPL / Dryden research team during a day off from the radar imaging missions. Although lava is not flowing from this crater, smoke and steam continue to rise into the air above the caldera. Lava continues to flow from Kilauea's east rift zone, the most active part of Kilauea, as it has since 1983. (NASA / Troy Asher)
NASA's Gulfstream III environmental research aircraft returned to the Dryden Aircraft Operations Facility in Palmdale, Calif., Jan. 14 following an eight-day deployment to Hawaii. Five science flights totaling more than 31 hours allowed scientists to collect radar imaging data about volcanoes intended to help scientists better understand processes occurring under Earth's surface.
NASA's Gulfstream-III research aircraft lifts off from the Edwards Air Force Base runway with the UAV synthetic aperture radar pod under its belly. (NASA / Tom Tschida) The airborne study was conducted from an altitude of 40,000 feet using the Uninhabited Aerial Vehicle Synthetic Aperture Radar, or UAVSAR, developed by NASA's Jet Propulsion Laboratory mounted in a pod under the aircraft. The study focused on the Kilauea volcano on the Big Island of Hawaii, the state's most active volcano, although science data flight lines were flown over nearby volcanoes including Mauna Loa, Mauna Kea, Hualalai and Kohala.
NASA research pilot Troy Asher reported that good weather and the reliability of the aircraft and the radar equipment enabled the research team to accomplish virtually all of their planned science data collection flight lines.
"We had one day off, and used that time to do a little touring on the island to see firsthand some of what we were observing from 40,000 feet," he added.
The UAVSAR uses a technique called interferometry that sends pulses of microwave energy from the sensor on the aircraft to the ground to detect and measure very subtle deformations in Earth's surface. The radar data collected during the mission will be analyzed over the next few weeks to determine if significant ground movement or deformation is occurring in the active volcanic areas.
The UAVSAR's first data acquisition over this region took place in January 2010. Assisted by a Platform Precision Autopilot designed by engineers at NASA's Dryden Flight Research Center, flights over the volcano were repeated in May 2011. Those two sets of observations successfully imaged the surface deformation caused by the March 2011 fissure eruption in Kilauea's east rift zone.