Unfortunately no technique exists for rigorous simulation of the complete imaging process, including the source, instrument, sample and detector. 2015, 2016), it is important to identify these minerals, a capability provided by Raman spectroscopy.The invention and advancement of biological microscopy depends critically on an ability to accurately simulate imaging of complex biological structures embedded within complex scattering media. Given the unexpectedly high abundances of feldspars (not generally recognized by near infrared spectroscopy) in igneous float rocks, conglomerates, and sedimentary outcrops in Aeolis Palus at Gale crater (e.g., Sautter et al. The power of Raman spectroscopy originates from the fact that the activity of Raman modes depends both on the form of a vibrational harmonic and the stereochemistry of the molecule in question. On the other hand, Raman can be insensitive to asymmetric stretches to which infrared spectroscopy is sensitive. Raman spectroscopy is sensitive to a symmetric stretch but infrared spectroscopy is not. These two mineralogy techniques are highly complementary, as Raman signals occur as a result of a change in polarizability of a molecule with atomic vibrations, whereas infrared spectroscopy is sensitive to a change in the dipole moments.
It was well understood that the Martian surface would benefit very strongly from a combination of remote Raman and visible-to-infrared (VISIR) reflectance spectroscopy.
A remote Raman-LIBS combination much closer in design to SuperCam was developed during the Venus Surface and Atmosphere Geochemical Explorer (SAGE) mission which only proceeded through Phase-A development (Clegg et al. 2007), but the LIBS was descoped early in the ExoMars development (Rull et al.
The first attempt was for the ExoMars rover (Courreges-Lacoste et al. 2005), and members of the SuperCam team sought to make that a reality over the years. It was recognized years ago that laser-induced breakdown spectroscopy (LIBS) and remote Raman spectroscopy both required a laser, a telescope, and an optical spectrometer (e.g., Wiens et al. This new instrument resulted from a happy collision of ideas from previous mission proposals. The SuperCam instrument is a response to this requirement for remote mineralogy while preserving the ability to remove dust prior to making observations of nearby targets, and providing the same or better chemistry and high-resolution imaging as ChemCam. Because of Curiosity’s relative lack of remote mineral-identification capabilities, the Mars 2020 Science Definition Team mandated that the next NASA rover should possess the ability to observe mineral compositions by remote sensing (Mustard et al. However, this passive spectral range is not diagnostic for phyllosilicates and carbonates, which are important for understanding the history of Mars’ hydration, climate, and habitability. ( 2015, 2017) to constrain the mineralogy of iron-bearing materials (e.g., hematite, olivine, and ferric sulfates). This spectrometer covers 535–853 nm ( \(105\text\) that allowed Johnson et al. The third is a high-efficiency transmission spectrometer containing an optical intensifier capable of gating exposures to 100 ns or longer, with variable delay times relative to the laser pulse. The light is split into three wavelength bands by a demultiplexer, and is routed via fiber bundles to three optical spectrometers, two of which (UV and violet 245–340 and 385–465 nm) are crossed Czerny-Turner reflection spectrometers, nearly identical to their counterparts on ChemCam. The BU, mounted inside the rover body, receives light from the MU via a 5.8 m optical fiber. Here we describe SuperCam’s body unit (BU) and testing of the integrated instrument. The on-board calibration targets are described in another companion paper. SuperCam is built in three parts: The mast unit (MU), consisting of the laser, telescope, RMI, IR spectrometer, and associated electronics, is described in a companion paper. A remote micro-imager (RMI) provides high-resolution color context imaging, and a microphone can be used as a stand-alone tool for environmental studies or to determine physical properties of rocks and soils from shock waves of laser-produced plasmas. These include laser-induced breakdown spectroscopy (LIBS), remote time-resolved Raman and luminescence spectroscopies, and visible and infrared (VISIR separately referred to as VIS and IR) reflectance spectroscopy.
The SuperCam instrument suite provides the Mars 2020 rover, Perseverance, with a number of versatile remote-sensing techniques that can be used at long distance as well as within the robotic-arm workspace. Space Science Reviews volume 217, Article number: 4 ( 2021) The SuperCam Instrument Suite on the NASA Mars 2020 Rover: Body Unit and Combined System Tests