On our planet, we occasionally witness the breathtaking glow of auroras, commonly known as the Northern Lights, caused by solar activity. However, Earth is not the only celestial body to experience this captivating phenomenon; planets like Mars and Neptune also exhibit auroras. Recently, the James Webb Space Telescope has captured extraordinary images of auroras on Jupiter, where these light displays are hundreds of times more intense than those seen on Earth.
Auroras occur when energetic particles from the sun interact with a planet’s atmosphere, usually near the magnetic poles. Observing these spectacular light shows on Jupiter not only offers stunning visuals but also provides astronomers with insights into the planet’s vast and complicated magnetosphere.
The auroras were first detected during Webb’s observations on December 25, 2023, with the findings only recently made public.
Lead researcher Jonathan Nichols from the University of Leicester, UK, expressed his astonishment, saying, “What a Christmas gift it was – I was completely blown away! We expected to see the auroras slowly fading in and out, perhaps over 15 minutes, but instead, we observed the entire auroral region sparkling and pulsing with light, sometimes changing from second to second.”
Jupiter’s auroras differ from those on Earth; they are influenced not only by solar storms but also by the planet’s powerful magnetic field. This magnetic field draws in charged particles from both the sun and its moon, Io, which is known for its volcanic activity. When volcanic eruptions on Io release particles into space, they can escape the moon’s gravity and become trapped in Jupiter’s orbit. As these particles accelerate due to Jupiter’s immense gravitational force, they collide with the atmosphere, creating that stunning glow.
However, many questions remain about these auroras. Researchers are puzzled by discrepancies between observations made by the Webb and Hubble space telescopes, which reveal different brightness levels in their images despite observing at various wavelengths.
“What makes these observations even more fascinating is that we captured images simultaneously in ultraviolet light with NASA’s Hubble Space Telescope,” Nichols noted. “Curiously, the brightest light observed by Webb didn’t have a counterpart in Hubble’s images. This has left us scratching our heads. To produce the brightness observed by both telescopes, we would expect a combination of a high amount of very low-energy particles impacting the atmosphere, which was previously deemed impossible. We still don’t fully grasp how this occurs.”