This can include creating maps of many minerals. The various layers can be assembled into materials maps which must be verified in the field to ensure the data were analyzed correctly and all relevant materials were included in the mapping process. It can take a couple of weeks or more to verify the results and begin to understand the complexities mapped. Laboratory and field spectrometers are required to calibrate imaging spectroscopy data, measure reference samples, and verify mapping results. Spectroscopy can be used to detect individual absorption features due to specific chemical bonds in a solid, liquid, or gas.
Every material is formed by chemical bonds, and has the potential for detection with spectroscopy.
The optical surface is the same as what the geologist sees in the field with his or her eyes. Diagnostic absorptions also exist due to other processes. NASA ER-2 flight is like launching a rocket through commercial airspace and requires significant advance planning on their part. Depending on the data requests, the aircraft may be deployed out of one of these locations for a several week period to acquire data near that base. Sites generally are found all over the United States.