ChemCam

ChemCam. It is a remote sensing instrument suite on board NASA's Curiosity rover, a key component of the Mars Science Laboratory mission. The instrument combines laser-induced breakdown spectroscopy (LIBS) and a high-resolution Remote Micro-Imager (RMI) to determine the elemental composition of rocks and soils from a distance. This capability allows scientists to analyze targets that are out of reach of the rover's arm or to quickly survey the geological diversity of the Martian landscape.

Overview

Mounted on the rover's mast, it represents a significant technological leap in planetary exploration, enabling rapid, non-contact geochemical analysis. Its primary purpose is to provide context for more detailed investigations by other instruments, such as the Alpha Particle X-Ray Spectrometer and the Sample Analysis at Mars suite. By vaporizing small amounts of material with a powerful laser, it can identify elements including hydrogen, lithium, strontium, and titanium. The data it provides is crucial for assessing past environmental conditions within Gale crater, particularly those relevant to astrobiology.

Instrument design

The design is a collaboration between the United States and France, led by the Los Alamos National Laboratory and the Centre National d'Études Spatiales. The LIBS system uses a pulsed neodymium-doped KGW laser to generate a plasma on targets up to seven meters away. Light from this plasma is collected by the rover's Cassegrain telescope and analyzed by three spectrometers covering ultraviolet, visible, and near-infrared wavelengths. The co-aligned Remote Micro-Imager provides contextual black-and-white images with a resolution five times higher than the Mastcams, allowing for precise targeting and documentation of laser pits.

Scientific results and discoveries

Since landing in 2012, its findings have fundamentally shaped our understanding of Martian geology. Early analyses at the Bradbury Landing site revealed compositions similar to mafic rocks found on Earth, such as basalt. It identified high concentrations of potassium and sodium in mineral veins, providing strong evidence for the past presence of liquid water. The instrument played a pivotal role in characterizing the clay-rich strata of the Murray formation and the salty, mineral-filled fractures of the Vera Rubin Ridge, supporting the hypothesis that Gale crater once contained a long-lived lake.

Operation on Mars

Daily operations are conducted by a dedicated team at NASA's Jet Propulsion Laboratory, with science planning led from the Los Alamos National Laboratory. The instrument typically performs one to two observation sessions per sol, often used to survey outcrops or select specific spots for subsequent contact science. Its rapid analysis capability was demonstrated during the traverse through the Bagnold Dunes, where it characterized active aeolian sand deposits. Data is relayed to Earth via the Mars Reconnaissance Orbiter and other orbiters in the Mars Exploration Program.

Development and team

The concept was originally proposed by a team led by Roger Wiens of Los Alamos National Laboratory. Development involved major contributions from the French Space Agency and institutions like the Institut de Recherche en Astrophysique et Planétologie in Toulouse. The international consortium includes scientists from American, French, Canadian, and Spanish research bodies. Its success paved the way for the enhanced SuperCam instrument on the Perseverance rover, which builds upon its foundational technology with added Raman spectroscopy and microphone capabilities.

Category:Mars Science Laboratory Category:Scientific instruments on spacecraft