A NIR spectrometer onboard Uvsq-Sat NG satellite for observing greenhouse gases

Uvsq-SatNG is a Six-Unit GHG CubeSat dedicated to the simultaneous measurements of the Earth Radiation Budget and greenhouse gases. This space mission aims to evaluate the potential of using a compact spectrometer mounted on a CubeSat for determining atmospheric GHG concentrations (CO₂, CH₄). This spectrometer operates in the Near-Infrared (NIR) range, typically between 1200 to 2000 nm, which is an ideal wavelength range for detecting and measuring the spectral signatures of the most significant greenhouse gases. The inclusion of such a spectrometer on Uvsq-SatNG represents an important step forward in climate research. It not only provides essential data for environmental science but also demonstrates the growing capability of satellite technology to support crucial observations of our planet’s changing climate. The aim of this article is to present an optical configuration for this instrument. The performance achieved with this design will be presented. We will see if the proposed instrument design is capable of measuring greenhouse gas concentrations with good accuracy (absolute measurements of ±4.0 ppm with an annual stability of ±1.0 ppm for CO₂, absolute measurements of ±25.0 ppb with an annual stability of ±10.0 ppb for CH₄).