Can Plants Glow? Tonight, a Satellite Blasts Off to Find Out!
Quick Summary
Tonight, a European rocket called Vega-C will carry two special satellites into space. One of them, called FLEX, will look for a secret glow that plants make when they are alive and growing. The other, Sentinel-3C, will keep watch over Earth’s oceans and land.
What Happened?
The launch is set for late tonight from Europe’s Spaceport in Kourou, French Guiana — a country on the coast of South America. Two satellites are packed together inside the rocket like two eggs in a single carton.
The first satellite is called Sentinel-3C. It is the third member of a family of Earth-watching satellites already circling our planet. Sentinel-3C uses powerful instruments to measure the temperature of the ocean, the health of land, the thickness of ice, and what is in the air above us. Scientists use this information for things like ocean and weather forecasting.
The second satellite is called FLEX, which stands for Fluorescence Explorer. This one is brand new and very exciting. When plants soak up sunlight to make food — a process called photosynthesis — they give off a tiny, invisible glow of light. You cannot see it with your eyes, but FLEX has a super-sensitive instrument called the FLORIS spectrometer that can detect this faint shine from hundreds of miles up in space.
By mapping where plants are glowing brightly and where they are not, scientists can figure out which forests and farms are healthy and which ones are struggling. It is like having a doctor’s tool that checks how Earth’s plants are feeling — from space!
The two satellites are stacked inside the rocket one on top of the other. Sentinel-3C rides on top and gets released first. Then FLEX, sitting below, gets released into its own orbit at about 814 kilometers high — roughly the distance from New York City to Chicago, but pointed straight up!
Why Does It Matter?
Plants are like Earth’s lungs. They absorb carbon dioxide and release oxygen. They also pull huge amounts of carbon out of the air. When plants are stressed — from drought, disease, or extreme heat — they glow less brightly. FLEX will help scientists keep track of plant health across the whole planet.
This information could help farmers know when their crops need water, help scientists track the effects of climate change on forests, and give world leaders better data for decisions about the environment.
Sentinel-3C joins its two older siblings already in orbit, making the whole monitoring network stronger.
Big Words
- photosynthesis — the way plants use sunlight, water, and air to make their own food
- fluorescence — a faint glow of light given off by something when it absorbs energy
- spectrometer — a scientific instrument that measures light and can reveal things invisible to the human eye
- Sun-synchronous orbit — a special path around Earth where the satellite always crosses the same spot at the same local time of day
- Copernicus Programme — Europe’s system of satellites designed to watch over Earth’s environment
Fun Fact
The glow that FLEX will detect is so faint that it is about one million times dimmer than the sunlight reflecting off leaves. Detecting it from space is a bit like spotting a single candle flickering inside a brightly lit stadium!
Think About It
If you could build a satellite to watch over Earth, what would you want it to look for — and why?
Sources
- ESA — FLEX and Sentinel-3C ready for launch (esa.int)
- Avio — AVIO TO LAUNCH COPERNICUS SENTINEL-3C AND FLEX SATELLITES ON SEPTEMBER 14th 2026
- NASASpaceFlight.com — Vega-C set to launch the ESA Sentinel-3C and FLEX missions from Kourou