New Environmental Measurement and Monitoring with 120,000 EMIT Imaging Spectroscopy Scenes Acquired Across Six Continents from the International Space Station.

The prime mission of the Earth Surface Mineral Dust Source Investigation (EMIT) was to characterize the mineral composition of the Earth’s arid land regions, deliver new constraints on the radiative forcing impacts of mineral dust aerosols in the Earth System today, and assess potential changes in the future. To achieve this objective, a high signal-to-noise ratio imaging spectrometer measuring the visible to short wavelength infrared (VSWIR) was developed and then launched to the International Space Station (ISS) on the 14^th of July 2022. Having measured more than 100 billion spectra across six continents, EMIT reported prime mission success on the 26^th of August 2024. Also in 2024, the EMIT mission was extended and the target observation areas expanded to include biodiversity, terrestrial ecology, corals, volcanos, coastal and inland waters, mid/low latitude snow/ice, and new geology regions across the six continents observable from the ISS.  In addition to new science, these extended mission observations support a broad set of new measurement and monitoring applications related to agriculture, forestry, critical minerals, water quality, wildfire fuels and burn severity, water resources, surface plastics, and more. In support of these objectives, >120,000 EMIT VSWIR imaging spectroscopy scenes have been measured and are currently available as radiance and reflectance along with a suite of mineralogy products. A new fractional cover product with photosynthetic vegetation, non-photosynthetic vegetation, soil, snow/ice, water, and char is in development. All EMIT data and products are freely available from the NASA Land Process Distributed Active Archive Center (LP DAAC). EMIT measurements and products include uncertainty estimates, and the project algorithms are available on GitHub. This contribution on remote sensing environmental monitoring presents new results from EMIT observations along with an overview of the measurements, products, and plans for the ongoing mission. EMIT observations also support preparatory activities for NASA’s Surface Geology and Biology Decadal Survey mission with a next-generation VSWIR imaging spectrometer that is part of the NASA Earth System Observatory and a companion mission to ESA’s Copernicus Hyperspectral Imaging Mission for the Environment (CHIME).