A spectrometer, utilizing an interference filter wedge, has been used to obtain spectra of reflected solar and emitted thermal radiation from earth in the wavelength interval 1.6 micro to 5.4 micro. Measurements were made, from a jet aircraft, of characteristic spectra of a wide variety of surface and cloud conditions during day and night flights. Measurements made concurrently from the airplane and the Nimbus II meteorological satellite verified the accuracy of the Nimbus measurements.