Astromat

Biconical FTIR reflectance spectrum of OREX-800073-0 aggregate sample of asteroid Bennu was measured with mostly light faces facing up, using Thermo Nexus 870 FTIR spectrometer with PIKE biconical diffuse reflectance accessory having a gold-coated mirror. The incidence and emergence rays are conically shaped. The incidence and emergence rays are off the plane perpendicular to the sample surface, and they are cone-shaped centering around 30 and -30 degrees from the vertical axis. This was a remeasurement of the same sample measured two months earlier to see any effect of water adsorption.