The Mastcam-Z Camera is a stereoscopic, multispectral camera with zoom ca pability on NASA’s Mars-2020 Perseverance rover. The Mastcam-Z relies on a set of two
deck-mounted radiometric calibration targets to validate camera performance and to provide
an instantaneous estimate of local irradiance and allow conversion of image data to units of
reflectance (R∗ or I/F) on a tactical timescale. Here, we describe the heritage, design, and optical characterization of these targets and discuss their use during rover operations. The
Mastcam-Z primary calibration target inherits features of camera calibration targets on the
Mars Exploration Rovers, Phoenix and Mars Science Laboratory missions. This target will
be regularly imaged during flight to accompany multispectral observations of the martian
surface. The primary target consists of a gold-plated aluminum base, eight strong hollow cylinder Sm2Co17 alloy permanent magnets mounted in the base, eight ceramic color and
grayscale patches mounted over the magnets, four concentric, ceramic grayscale rings and
a central aluminum shadow post (gnomon) painted with an IR-black paint. The magnets
are expected to keep the central area of each patch relatively free of Martian aeolian dust.
The Mastcam-Z secondary calibration target is a simple angled aluminum shelf carrying
seven vertically mounted ceramic color and grayscale chips and seven identical, but hori zontally mounted ceramic chips. The secondary target is intended to augment and validate
the calibration-related information derived from the primary target. The Mastcam-Z radio metric calibration targets are critically important to achieving Mastcam-Z science objectives
for spectroscopy and photometric properties
