Mastcam-Z is a multispectral, stereoscopic imaging investigation on the Mars 2020 mission’s
Perseverance
rover. Mastcam-Z consists of a pair of focusable, 4:1 zoomable cameras that provide broadband ...red/green/blue and narrowband 400-1000 nm color imaging with fields of view from 25.6° × 19.2° (26 mm focal length at 283 μrad/pixel) to 6.2° × 4.6° (110 mm focal length at 67.4 μrad/pixel). The cameras can resolve (≥ 5 pixels) ∼0.7 mm features at 2 m and ∼3.3 cm features at 100 m distance. Mastcam-Z shares significant heritage with the Mastcam instruments on the Mars Science Laboratory
Curiosity
rover. Each Mastcam-Z camera consists of zoom, focus, and filter wheel mechanisms and a 1648 × 1214 pixel charge-coupled device detector and electronics. The two Mastcam-Z cameras are mounted with a 24.4 cm stereo baseline and 2.3° total toe-in on a camera plate ∼2 m above the surface on the rover’s Remote Sensing Mast, which provides azimuth and elevation actuation. A separate digital electronics assembly inside the rover provides power, data processing and storage, and the interface to the rover computer. Primary and secondary Mastcam-Z calibration targets mounted on the rover top deck enable tactical reflectance calibration. Mastcam-Z multispectral, stereo, and panoramic images will be used to provide detailed morphology, topography, and geologic context along the rover’s traverse; constrain mineralogic, photometric, and physical properties of surface materials; monitor and characterize atmospheric and astronomical phenomena; and document the rover’s sample extraction and caching locations. Mastcam-Z images will also provide key engineering information to support sample selection and other rover driving and tool/instrument operations decisions.
The Planetary Instrument for X-ray Lithochemistry (PIXL) onboard the
Perseverance
rover, part of NASA’s Mars 2020 mission, has the first camera system that utilizes active light sources to generate ...multispectral data directly on a planetary surface. PIXL collects the multispectral data using three different components in the Optical Fiducial System (OFS): Micro Context Camera (MCC), Floodlight Illuminator (FLI), and Structure light illuminator (SLI). MCC captures images illuminated at different wavelengths by FLI while topography information is obtained by synchronously operating the MCC and SLI. A radiometric calibration for such a system has not been attempted before. Here we present a novel radiometric correction process and verify the output to a mean error of 0.4% by comparing it to calibrated spectral data from the Three Axis N-sample Automated Goniometer for Evaluation Reflectance (TANAGER). We demonstrate that the radiometrically corrected data can clearly discern different features in natural rock and mineral samples. We also conclude that the same radiometric correction process can be used on Mars as the optical system is designed to autonomously compensates for the effects of the Martian environment on the instrument. Having multispectral capabilities has proven to be very valuable for extrapolating the detailed mineral and crystallographic information produced by X-ray spectroscopy from the X-ray system of PIXL.
The NASA
Perseverance
rover Mast Camera Zoom (Mastcam-Z) system is a pair of zoomable, focusable, multi-spectral, and color charge-coupled device (CCD) cameras mounted on top of a 1.7 m Remote ...Sensing Mast, along with associated electronics and two calibration targets. The cameras contain identical optical assemblies that can range in focal length from 26 mm (
25.5
∘
×
19.1
∘
FOV
) to 110 mm (
6.2
∘
×
4.2
∘
FOV
) and will acquire data at pixel scales of 148-540 μm at a range of 2 m and 7.4-27 cm at 1 km. The cameras are mounted on the rover’s mast with a stereo baseline of
24.3
±
0.1
cm and a toe-in angle of
1.17
±
0.03
∘
(per camera). Each camera uses a Kodak KAI-2020 CCD with
1600
×
1200
active pixels and an 8 position filter wheel that contains an IR-cutoff filter for color imaging through the detectors’ Bayer-pattern filters, a neutral density (ND) solar filter for imaging the sun, and 6 narrow-band geology filters (16 total filters). An associated Digital Electronics Assembly provides command data interfaces to the rover, 11-to-8 bit companding, and JPEG compression capabilities. Herein, we describe pre-flight calibration of the Mastcam-Z instrument and characterize its radiometric and geometric behavior. Between April 26
t
h
and May 9
t
h
, 2019, ∼45,000 images were acquired during stand-alone calibration at Malin Space Science Systems (MSSS) in San Diego, CA. Additional data were acquired during Assembly Test and Launch Operations (ATLO) at the Jet Propulsion Laboratory and Kennedy Space Center. Results of the radiometric calibration validate a 5% absolute radiometric accuracy when using camera state parameters investigated during testing. When observing using camera state parameters not interrogated during calibration (e.g., non-canonical zoom positions), we conservatively estimate the absolute uncertainty to be
<
10
%
. Image quality, measured via the amplitude of the Modulation Transfer Function (MTF) at Nyquist sampling (0.35 line pairs per pixel), shows
MTF
Nyquist
=
0.26
−
0.50
across all zoom, focus, and filter positions, exceeding the
>
0.2
design requirement. We discuss lessons learned from calibration and suggest tactical strategies that will optimize the quality of science data acquired during operation at Mars. While most results matched expectations, some surprises were discovered, such as a strong wavelength and temperature dependence on the radiometric coefficients and a scene-dependent dynamic component to the zero-exposure bias frames. Calibration results and derived accuracies were validated using a Geoboard target consisting of well-characterized geologic samples.
The Mastcam-Z Camera is a stereoscopic, multispectral camera with zoom capability 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 Sm
2
Co
17
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 horizontally mounted ceramic chips. The secondary target is intended to augment and validate the calibration-related information derived from the primary target. The Mastcam-Z radiometric calibration targets are critically important to achieving Mastcam-Z science objectives for spectroscopy and photometric properties.
Systems Engineering of the Psyche Payload De Soria-Santacruz, M.; Bates-Tarasewicz, H. A.; Chhit, W. S. ...
2024 IEEE Aerospace Conference,
2024-March-2
Conference Proceeding
The Psyche mission is a journey to a unique metal asteroid of the same name, (16) Psyche, orbiting the Sun between Mars and Jupiter. Psyche launched October 13 th , 2023 from Kennedy Space Center. ...The mission seeks to answer questions about the formation of planets and explore what may be an exposed nickel-iron core of an early planetesimal, similar to the one hidden at the center of our own Earth. The mission is led by Arizona State University. NASA's Jet Propulsion Laboratory is responsible for mission management, systems engineering, operations, navigation, and some subsystems including command and data handling and telecommunications. This paper focuses on the Psyche Payload System, which consists of a multispectral Imager, a Magnetometer, a Gamma-Ray and Neutron Spectrometer (GRNS), and a Deep Space Optical Communications (DSOC) experiment. The GRNS will measure the asteroid's composition, the Magnetometer will determine whether Psyche is a core by measuring any remnant magnetic field, and the Imager will map its surface and characterize its topography. DSOC is a technology demonstration hosted by the Psyche spacecraft and intended to pave the way for low-power/high-bandwidth communications in deep space using individual photons to encode and transmit information. This paper focuses on the Payload development efforts and key systems engineering processes that made it possible including requirements development, risk reduction activities, key challenges and anomalies, verification and validation, and the final stretch to launch during assembly and test with the integrated spacecraft.
Focused electron beam induced deposition (FEBID) is a direct-writing technique with nanometer resolution, which has received strongly increasing attention within the last decade. In FEBID a precursor ...previously adsorbed on a substrate surface is dissociated in the focus of an electron beam. After 20 years of continuous development FEBID has reached a stage at which this technique is now particularly attractive for several areas in both, basic and applied research. The present topical review addresses selected examples that highlight this development in the areas of charge-transport regimes in nanogranular metals close to an insulator-to-metal transition, the use of these materials for strain- and magnetic-field sensing, and the prospect of extending FEBID to multicomponent systems, such as binary alloys and intermetallic compounds with cooperative ground states.
After a brief introduction to the technique, recent work concerning FEBID of Pt-Si alloys and (hard-magnetic) Co-Pt intermetallic compounds on the nanometer scale is reviewed. The growth process in the presence of two precursors, whose flux is independently controlled, is analyzed within a continuum model of FEBID that employs rate equations. Predictions are made for the tunability of the composition of the Co-Pt system by simply changing the dwell time of the electron beam during the writing process. The charge-transport regimes of nanogranular metals are reviewed next with a focus on recent theoretical advancements in the field. As a case study the transport properties of Pt-C nanogranular FEBID structures are discussed. It is shown that by means of a post-growth electron-irradiation treatment the electronic intergrain-coupling strength can be continuously tuned over a wide range. This provides unique access to the transport properties of this material close to the insulator-to-metal transition. In the last part of the review, recent developments in mechanical strain-sensing and the detection of small, inhomogeneous magnetic fields by employing nanogranular FEBID structures are highlighted.
FEBID has now reached a state of maturity that allows a shift of the focus towards the development of new application fields, be it in basic research or applied. This is shown for selected examples in the present review. At the same time, when seen from a broader perspective, FEBID still has to live up to the original idea of providing a tool for electron-controlled chemistry on the nanometer scale. This has to be understood in the sense that, by providing a suitable environment during the FEBID process, the outcome of the electron-induced reactions can be steered in a controlled way towards yielding the desired composition of the products. The development of a FEBID-specialized surface chemistry is mostly still in its infancy. Next to application development, it is this aspect that will likely be a guiding light for the future development of the field of focused electron beam induced deposition.
The sensitivity and detection speed of cantilever-based mechanical sensors increases drastically through size reduction. The need for such increased performance for high-speed nanocharacterization ...and bio-sensing, drives their sub-micrometre miniaturization in a variety of research fields. However, existing detection methods of the cantilever motion do not scale down easily, prohibiting further increase in the sensitivity and detection speed. Here we report a nanomechanical sensor readout based on electron co-tunnelling through a nanogranular metal. The sensors can be deposited with lateral dimensions down to tens of nm, allowing the readout of nanoscale cantilevers without constraints on their size, geometry or material. By modifying the inter-granular tunnel-coupling strength, the sensors' conductivity can be tuned by up to four orders of magnitude, to optimize their performance. We show that the nanoscale printed sensors are functional on 500 nm wide cantilevers and that their sensitivity is suited even for demanding applications such as atomic force microscopy.
Air- and water-stable, π-conjugated −donor–acceptor− n oligomers containing thiophene fragments as donors and 9,10-dimesityl-9,10-dihydro-9,10-diboraanthracene (DBA(Mes)2) as acceptor units were ...prepared through Stille-type C–C-coupling protocols. The reaction between 2,6-dibromo-DBA(Mes)2 (1), 2,7-dibromo-DBA(Mes)2 (2), 2-bromo-6,7-dimethyl-DBA(Mes)2 (3), and 2,5-bis(trimethylstannyl)thiophene (7) furnished monodisperse, short-chain model systems 8 0 (2 × DBA(Mes)2, 1 × 2,5-thienylene) and 8 1 (3 × DBA(Mes)2, 2 × 2,5-thienylene) after GPC separation. In the absence of 3, the oligomerization of 1/2 with 7 provided analogous longer chain macromolecules 9 (MALDI–MS reveals up to 7 repeating units; GPC indicates also significantly longer chains). UV/vis absorption spectroscopy suggests that the obtained chain lengths of 9 are already sufficient to reach the maximum effective conjugation length (the lower limit of the HOMO–LUMO band gap corresponds to 2.3 eV). 9 gives rise to a dark orange fluorescence, both in C6H6 solution (ϕf = 47%) and as thin film (ϕf = 13%).
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