A new tool will soon allow researchers to analyze the Earth’s surface in fascinating detail, from the state of the planet’s soil to the plants that thrive on its surface to the composition of cities. This spring, a SpaceX Falcon 9 rocket lifted off from Florida to deliver a €300 million German Environmental Mapping and Analysis Program (EnMAP) satellite into orbit. Starting this fall, remote sensing researchers around the world can apply to guide the spacecraft to specific targets as it orbits the globe from pole to pole. “We are very excited,” says Sabine Chabrilat, principal investigator of EnMAP, an Earth scientist at the German Research Center for Earth Sciences in Potsdam and the Leibniz University in Hannover. “We’re really confident that we’re going to get high-quality data.”
EnMAP belongs to the next generation of so-called hyperspectral missions, which promise to fill a big gap in remote sensing. Compared to conventional cameras and multispectral cameras, hyperspectral sensors more accurately record a much wider part of the electromagnetic spectrum, capturing the characteristic wavelengths reflected from different materials. While other satellites track urban sprawl from space, these spectral fingerprints can show how much of the sprawl is related to, say, housing versus asphalt. And where other satellites detect toxic algal blooms, hyperspectral data can pinpoint the phytoplankton species responsible. “This will greatly improve our understanding of biodiversity around the world,” says Susan Ustin, director of the Center for Spatial Technologies and Remote Sensing at the University of California, Davis, who is not involved in the mission.
Chabrillat looks forward to analyzing Earth’s soil, which faces increasing damage from industrial agriculture and climate change. Grud grows food and stores carbon, but monitoring its global health is difficult. “We really lack an assessment of the current state of our soils,” she says. “Did they degrade? How much have they degraded? Where are the foci of degradation?” EnMAP will help answer these questions at a glance.
Scientists have recognized the potential of space-based hyperspectral imaging since the 1980s, but new missions have been few and far between. “NASA executives were skeptical about the potential of funding a satellite mission that could solve many environmental and scientific questions, saying that a mission that acts like a Swiss army knife would not fly,” explains Elizabeth Middleton, who was a mission scientist on NASA’s EO-1 , an advanced hyperspectral demonstration mission that operated from 2000 to 2017. This thinking has changed. “With more concern about climate change and resilience to climate change, there is a growing demand for more accurate information for the environment,” says Ustin.
The freely available EnMAP data will complement observations from other missions, such as the Italian demonstration spacecraft PRISMA, which launched in 2019. Both NASA and the European Space Agency aim to launch large hyperspectral missions by the end of the decade to further expand our views of the planet’s surface.