And they never end!
Jupiter, the largest planet in our solar system, is probably best known for its Great Red Spot — an enormous anticyclonic (high pressure) storm that has lasted for at least 400 years. However, the planet also features another beautiful natural phenomenon: auroras.
Using the NASA/ESA Hubble Space Telescope, astronomers were able to observe as well as capture images of Jupiter’s beautiful auroras.
Auroras are created when fast-moving electrons ejected from the sun enter a planet’s atmosphere near its magnetic poles, which collide with atoms of gas. The auroras on Jupiter, which were first discovered by Voyager 1 in 1979, cover areas bigger than Earth, are hundreds of times more energetic than auroras on Earth, and they never end.
On Earth, intense auroras are caused by solar storms — when high-energy particles interact with gases, such as nitrogen and oxygen, in the upper atmosphere, causing them to glow red, green, purple, and white — but Jupiter has an additional source for its auroras.
The strong magnetic field of Jupiter actually snatches charged particles from its surroundings.
Not only does it capture charged particles from the solar wind, but it also grabs onto particles thrown into space by its orbiting moon Io, which has numerous large volcanic eruptions.
To capture detailed images of Jupiter’s auroras, Hubble will be observing the planet daily for about a month. Then, using a series of images, scientists will create videos showing the movement of the auroras.
Luckily, Hubble’s observations are perfectly timed with NASA’s Juno spacecraft, which is currently in the solar wind near Jupiter, and will be entering its orbit early in July 2016. While Hubble is observing and measuring the auroras of Jupiter, Juno will be assessing the properties of the solar wind. A perfect pairing!
“These auroras are very dramatic and among the most active I have ever seen”, said Jonathan Nichols from the University of Leicester, UK, and principal investigator of the study, in a Hubble news release. “It almost seems as if Jupiter is throwing a firework party for the imminent arrival of Juno.”
The hope is that this new information will provide scientists with a better understand of how the sun and other sources affect auroras, and how Jupiter’s auroras respond to changing conditions of the solar wind.
The first videos are already available showing the auroras on Jupiter’s north pole. They are really quite beautiful — you can watch one below.