The European Space Agency has planned seven different Earth Explorer satellites, all of which have had specific missions for studying what makes our planet work, like gravity and magnetic fields, soil moisture, ocean salinity and more. These satellites not only answer questions about our world, but help us determine how us human have impacted it and what we need to change.
The eighth Earth Explorer mission has been announced and it will study a particularly important subject as we head into the future: the health of the Earth's plants. Set to launch by 2022, the ESA says the satellite called FLEX "will track the health of the world’s vegetation by detecting and measuring the faint glow that plants give off as they convert sunlight and the atmosphere’s carbon dioxide into energy.
Yielding information about the health and stress of the planet’s vegetation is important as the growing global population places increasing demands on the production of food and animal feed."
The satellite will do that by monitoring the way carbon moves between plants and the atmosphere and also how photosynthesis affects the carbon and water cycles.
The tools aboard the satellite will be the first ever to measure photosynthetic activity from space. FLEX, short for Fluorescence Explorer, will feature a new sensor that can detect the faint fluorescence that plants give off during photosynthesis. That fluorescence is dimmer or unable to be detected if a plant is unhealthy or under environmental stress.
FLEX will orbit together with one of the Copernicus Sentinel-3 satellites to make use of its optical and thermal sensors to see the fully story of the health of Earth's plants and what's affecting them.
The fluorescence sensor was tested earlier this year on an aircraft-mounted imaging spectrometer where it measured the fluorescence of two turf fields. One of the fields was treated with herbicide, which weakened the plants' ability to collect solar energy. The instrument was able to detect a stronger glow from the untreated field and the treated field showed up as unhealthy, as you can see in the image above.
Jan Woerner, ESA’s Director General, said, “FLEX will give us new information on the actual productivity of vegetation that can be used to support agricultural management and the development of a sustainable bioeconomy. It will therefore help to understand our ecosystem.”
Let's hope this technology really does help us to solve the difficult challenges of feeding more people while preserving precious ecosystems.