On Jupiter, never-ending auroras seem to be ‘throwing a fireworks party’ for approaching NASA craft

On Jupiter, Fourth of July fireworks last year-round.

New images from the Hubble Space Telescope reveal a new feature of the gas giant: brilliant blue auroras.

“These auroras are very dramatic and among the most active I have ever seen,” Jonathan Nichols, who studies auroras at the University of Leicester, said in a statement. “It almost seems as if Jupiter is throwing a fireworks party for the imminent arrival of Juno.”

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NASA’s Juno spacecraft is on track to begin orbiting Jupiter on July 4. The space agency announced Thursday that the craft has entered the planet’s magnetic field.

During its 20-month mission, it will measure the composition of the gas giant’s atmosphere, search for a core and help determine how the planet itself — and solar systems in general — are formed.

The mission will also explore the Jupiter’s polar regions, especially its northern and southern lights.

As Juno approaches Jupiter, it is collecting data on the solar wind, which partly feeds the planet’s auroras. Jupiter grabs charged particles from the solar wind, as well as its volcanic moon.

As the particles rain down on the atmosphere, they collide with gas atoms and cause them to glow. On Earth, auroras produce a temporary display of red, green and purple lights. On Jupiter, they never stop. They’re also hundreds of times more powerful than those on Earth and cover larger areas.

The Jovian auroras were first detected in 1979 by Voyager 1. But that spacecraft only saw a thin, stretched-out version of Earth’s auroras on the nightside of the planet.

To get the best view of the aurora, you have to look at it in ultraviolet light.

Using Hubble, astronomers are watching Jupiter’s auroras every day for a month. The resulting images and videos will show how the lights move about on the planet’s poles.

Scientists hope to use Hubble’s new observations, along with Juno’s measurements, to learn more about how the sun and other sources influence auroras.

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