NASA Public Affairs Office
Stennis Space Center, MS 39529-6000
Two NASA scientists recently hitched a ride with the Naval Research Laboratory (NRL) aboard the Research Vessel Seward Johnson II to cooperate in data collection in the Gulf of Mexico.
Stennis Space Center's Bruce Spiering with the Technology Development and Transfer Office in NASA's Program Development Directorate; and Callie Hall, oceanographer with NASA's Applied Sciences Directorate (ASD), participated in the NRL's Slope-to-Shelf Energetics and Exchange Dynamics (SEED) cruise in mid-November. While aboard, Spiering and Hall used ASD's optical instrument profiling package to take measurements and water samples at several locations in the Gulf - approximately 60 miles south of Mobile Bay.
The study area lies just east of the mouth of the Mississippi River, on the same latitude as the river's mouth. The scientists will be able to use optical measurements and samples in their ongoing evaluation of the bio-optic properties to determine the river plume's influence on the Gulf of Mexico's waters.
The research is part of NASA's larger scientific exploration of the Earth under the Vision for Space Exploration – to advance understanding of the Earth-Sun system, to bring the lessons of the study of Earth to the exploration of our solar system and to understand how our planet and star are changing.
Hall and Spiering's work focuses on analyzing and verifying satellite imagery from the MODIS (Moderate Resolution Imaging Spectrometer) sensor on NASA's Aqua and Terra Earth Observing satellites.
"We're trying to make sense of how light interacts with mineral and organic particles in the water," Spiering said.
Ocean color satellites were designed to work over clear, open ocean waters, he said. The closer to the coast an image is taken, the more clouded the water is. By collecting water samples alongside measurements of water optical properties, researchers can correlate particle characteristics with their influence on the underwater light field.
Spiering and Hall also will use the recently gathered water samples to analyze properties such as concentrations of phytoplankton (microscopic plant) pigment, nutrients and total suspended matter.
"We hope to participate in more cooperative projects with NRL," Hall said. "NASA must use ships of opportunity to validate its ocean color algorithms. The data collected during this cruise help NASA and NRL meet their science goals."
The NRL's SEED project aims to understand the physical processes that control water properties along the Continental Shelf break, where the ocean floor plummets from depths of 200 feet to more than a mile. In May, NRL's Oceanography Division deployed mooring-mounted sensors in the study area. In November, NRL serviced the sensors and retrieved data that will help them create ocean models. The NASA scientists hope to work with NRL on future cruises.
"We want to share data," Spiering said, "and we share the workload. It benefits everybody."
News releases provided by NASA's Stennis Space Center are available at
For more information, call the NASA Public Affairs Office at Stennis at 1-800-237-1821 in Mississippi and Louisiana only, or (228) 688-3341.
- end -