  The Quantitative Reflectance Imaging System (QRIS) is a laboratory-based
spectral imaging system constructed to image the sample of asteroid Bennu
delivered to Earth by the Origins, Spectral Interpretation, Resource
Identification, and Security-Regolith Explorer (OSIRIS-REx) spacecraft. The
system was installed in the OSIRIS-REx cleanroom at NASA's Johnson Space Center
to collect data during preliminary examination of the Bennu sample. QRIS uses a
12-bit machine vision camera to measure reflectance over wavelength bands
spanning the near ultraviolet to the near infrared. Raw data are processed by a
calibration pipeline that generates a series of monochromatic,
high-dynamic-range reflectance images, as well as band ratio maps, band depth
maps, and 3-channel color images. The purpose of these spectral reflectance
data is to help characterize lithologies in the sample and compare them to
lithologies observed on Bennu by the OSIRIS-REx spacecraft. This initial
assessment of lithological diversity was intended to help select the subsamples
that will be used to address mission science questions about the early solar
system and the origins of life and to provide important context for the
selection of representative subsamples for preservation and distribution to
international partners. When QRIS imaged the Bennu sample, unexpected
calibration issues arose that had not been evident at imaging rehearsals and
negatively impacted the quality of QRIS data. These issues were caused by stray
light within the lens and reflections off the glovebox window and interior, and
were exacerbated by the sample's extremely low reflectance. QRIS data were
useful for confirming conclusions drawn from other data, but reflectance and
spectral data from QRIS alone unfortunately have limited utility.
