ESA’s FLEX mission reveals the secret glow of plants

Plants may look still and silent, but every leaf is constantly responding to its environment.

As plants photosynthesise, they emit an incredibly faint glow called fluorescence. Invisible to our eyes, this signal can reveal how plants are using sunlight and how they respond to heat, drought, pests and other environmental stresses.

ESA’s Fluorescence Explorer, or FLEX, will detect this faint signal from space. Using its highly sensitive FLORIS instrument, FLEX will map plant fluorescence across Earth, giving scientists a new way to observe plant health and photosynthetic activity on a global scale.

These observations will help us better understand how vegetation responds to a changing climate, including the effects of drought, and improve our understanding of the global carbon and water cycles.

Every leaf tells a story. With FLEX, we’re learning how to read it.