A glow emanates from Earth's thriving land plants.
A healthy plant is a glowing plant. That's because healthy plants that engage in photosynthesis—convert sunlight to energy—also emit fluorescent light. It's the same physical process that makes everyday objects glow in the dark. While human eyes are unable to detect the faint glow from plants, satellites hundreds of miles above Earth are up to the task. A team of researchers led by NASA scientists identified the fluorescence fingerprint in data collected by an instrument on a European meteorological satellite. A visualization of the data, released in 2013, allows scientists for the first time to see global changes in terrestrial plant fluorescence over the course of a month. That means a front-row seat to track the northward migration of plant blooming during the Northern Hemisphere springtime, as well as the shut down in fall—even before changing leaf colors indicate a seasonal shift is amiss. Watch the visualization for a tour of plant fluorescence around the world.