Researchers Develop Method to Predict Rare Green Auroral Events on Mars

Mars, often called the Red Planet, can sometimes light up emerald green in the night sky. In March 2024, the Perseverance rover captured the first visible aurora from the Martian surface. Now researchers say they have learned how to forecast these rare green displays by tracking powerful solar storms heading toward Mars. Until now, predicting Martian auroras had been essentially a trial-and-error process. The advance warning could help future astronauts seek shelter from dangerous radiation released during the same storm.

Forecasting Martian Auroras

According to a statement, researchers programmed the Perseverance rover to watch the sky after any coronal mass ejection (CME) blasts toward Mars. These solar storms hurl charged particles into Mars's atmosphere, and the faster the CME, the more likely it triggers a visible aurora. Because it takes about three days to send commands to the rover, teams must predict in advance which storms to observe. Early attempts failed when CMEs were too weak; focusing on faster, stronger storms, the researchers eventually captured two green auroras on Mars.

Directions for human exploration

On Mars, auroras are produced when charged solar particles strike oxygen in the atmosphere, giving the planet a green glow. The source of this glow is about 100 kilometres above the ground. Indeed, scientists predict that the auroras may be visible from Mars with the unaided eye. Strong storms can cause the entire night sky to glow green because Mars lost its magnetic field a long time ago, unlike Earth, which has polar lights. The same solar eruptions are beautiful, but they also emit dangerous radiation. It's critical to anticipate their arrival because astronauts on Mars could then seek shelter from this radiation.