NASA's EMIT Generates Image Cube of Surface Minerals in Northwest Nevada
The front panel of this image cube shows the true-color view of an area in northwest Nevada observed by NASA's Earth Surface Mineral Dust Source Investigation (EMIT) imaging spectrometer. The side panels depict the spectral fingerprint for every point in the image, which shows an area about 130 miles (209 kilometers) northeast of Lake Tahoe.
The instrument works by measuring reflected solar energy from Earth across hundreds of wavelengths from the visible to the infrared range of the spectrum. The intensity of the reflected light varies by wavelength based on the material. Scientists are using these patterns, called spectral fingerprints, to identify surface minerals and pinpoint their locations on a map.
The cube was among the first created by EMIT scientists as they confirmed that the instrument was collecting data accurately before the start of science operations. Analysis of the patterns indicate areas dominated by kaolinite, a light-colored clay mineral. When dust from the kaolinite-dominated areas is lofted into the atmosphere, the particles tend to scatter sunlight and reflect it back to space, cooling the air.
Over the course of its 12-month mission, EMIT will collect measurements of 10 important surface minerals – kaolinite, hematite, goethite, illite, vermiculite, calcite, dolomite, montmorillonite, chlorite, and gypsum – in arid regions between 50-degree south and north latitudes in Africa, Asia, North and South America, and Australia. The data EMIT collects will help scientists better understand the role of airborne dust particles in heating and cooling Earth's atmosphere on global and regional scales.
Since EMIT was installed on the International Space Station in late July 2022, the science team has been validating the data it collects against data gathered in 2018 by the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS). EMIT and AVIRIS were developed at NASA's Jet Propulsion Laboratory, which is managed for the agency by Caltech in Pasadena, California.