NASA's HyspIRI Mission: Seeing the forest and the trees

Temperature information was collected simultaneously by the MASTER instrument. 

Red areas are composed of minerals with high silica, such as urban areas, while darker and cooler areas are composed of water and heavy vegetation. 

Credit: NASA

To Robert Green, light contains more than meets the eye: It contains fingerprints of materials that can be detected by sensors that capture the unique set of reflected wavelengths.

Scientists have used the technique, called imaging spectroscopy, to learn about water on the moon, minerals on Mars and the composition of exoplanets.

Green's favorite place to apply the technique, however, is right here on the chemically rich Earth, which is just what he and colleagues achieved this spring during NASA's Hyperspectral Infrared Imager (HyspIRI) airborne campaign.

"We have ideas about what makes up Earth's ecosystems and how they function," said Green, of NASA's Jet Propulsion Laboratory in Pasadena, Calif., and principal investigator of the campaign's Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) instrument.

"But a comprehensive understanding requires us to directly measure these things and how they change over landscapes and from season to season."

Toward that goal, scientists and engineers ultimately plan to launch the HyspIRI satellite—a mission recommended by the 2007 National Academy of Sciences Decadal Survey—to determine the spectral and thermal characteristics of the world's ecosystems, which are sensitive to changes in vegetation health, as well as detecting and understanding changes in other surface phenomena including volcanoes, wildfires and droughts.

Prior to flying the sensors in space, however, preparatory science investigations are underway using similar sensor technology installed on NASA's ER-2, a high-altitude aircraft based at NASA's Dryden Aircraft Operations Facility in Palmdale, Calif.

The first season of the HyspIRI airborne campaign concludes on April 25 after about a month of flights that spanned the state. Additional sets of California flights are planned for this summer and then this fall.

"We are collecting data over six zones across very diverse regions of California, from the coast to high-elevation terrain, from alpine areas to deserts to coastal ecosystems, and from agricultural to urban landscapes," Green said.

For example, the campaign's first test flight on March 29 collected data along a series of parallel flight lines.

The resulting image covers about six miles in width and almost 100 miles in length. One flight happened to pass over the San Andreas Fault. Inclusion of the fault in the flight plan was incidental, but it was a "spectacular" flight nonetheless, Green said.