ESA plans to 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.

Following a rigorous selection process, the satellite will be ESA’s eighth Earth Explorer, planned for launch by 2022.

As well as yielding important information about plant health, the Fluorescence Explorer – FLEX – satellite will improve our understanding of the way carbon moves between plants and the atmosphere and how photosynthesis affects the carbon and water cycles.

The conversion of atmospheric carbon dioxide and sunlight into energy-rich carbohydrates through photosynthesis is one of the most fundamental processes on Earth – and one on which we all depend.

Although most people have heard of photosynthesis, the process involves an extremely complex chain of events.

Working in sequence, there are two different ‘solar power systems’ inside plant and algae cells. They collect energy in sunlight and produce chemical energy for photosynthesis and heat.

In addition, the process involves a faint fluorescence, subject to environmental conditions and the health of the plant.