Jupiter may be best known for its famous Great Red Spot, but astronomers using the Hubble Space Telescope have captured some dramatic images of a different feature -- monstrous auroras dancing atop the solar system's biggest planet.
The space-based telescope has been observing Jupiter almost daily for several months using its far-ultraviolet cameras, creating a series of photos and videos showing the auroras, which cover an area larger than Earth.
Not only are the auroras huge in size, they are also hundreds of times more energetic than auroras on Earth. And while Earth's most intense auroras are caused by solar storms -- when charged particles rain down on the upper atmosphere, excite gases, and cause them to glow red, green and purple -- Jupiter has an additional source for its auroras.
The huge planet's strong magnetic field grabs charged particles from its surroundings. This includes not only the charged particles within the solar wind but also the particles thrown into space by its orbiting moon Io, known for its numerous and large volcanoes.
Hubble's observations come just ahead of the arrival of NASA's Juno probe, which will enter orbit around the gas giant next month. Juno will be able to measure first-hand the properties of the solar wind in what NASA calls a perfect collaboration between a telescope and a space probe.
"These auroras are very dramatic and among the most active I have ever seen", said Jonathan Nichols from the University of Leicester, U.K., and principal investigator of the study. "It almost seems as if Jupiter is throwing a firework party for the imminent arrival of Juno."
NASA says the new observations and measurements made with Hubble and Juno will help to better understand how the sun and other sources influence auroras throughout the solar system.