Hubble captures mysterious aurora the size of Earth over Jupiter’s north pole 

NASA’s Juno spacecraft is closing in on Jupiter. Here the Daily Mail Online reviews the project from a layman’s perspective.

On Earth they produce mesmerising riots of colour that light up the night sky around the poles. But our planet is not the only world to enjoy stunning aurora – better known as the northern and southern lights.

Now scientists are hoping to unravel the secrets of the biggest such polar light show in our solar system by focusing their attention on Jupiter’s aurora.

They are using the Hubble Space Telescope to study the giant planet’s atmospheric light shows, which cover an area larger than the entire Earth. New images captured by the telescope reveal the flickers and flashes produced as high energy particles in the solar wind collide with gases over Jupiter’s poles.

This produces vivid ultraviolet displays that cap the giant planet.
Astronomers are combining the observations with data being collected by Nasa’s Juno spacecraft as it races towards Jupiter.

The probe is currently surfing through the solar wind as it prepares to enter orbit around Jupiter on July 4. It is designed to help scientists unpick how Jupiter’s giant magnetic field interacts with the supersonic solar wind. They also hope to discover what may be causing the magnetic field, as many believe the huge ball of gas may have a solid core.

Dr Jonathan Nichols, a space scientist at the University of Leicester who is taking part in the Jupiter aurora project, said: ‘These auroras are very dramatic and among the most active I have ever seen.
‘It almost seems as if Jupiter is throwing a firework party for the imminent arrival of Juno.’

Hubble is spending a month observing Jupiter daily to help scientists understand how the aurora form on the largest planet in the solar system. By comparing the aurora to data from Juno about the solar wind, it will help scientists unravel the influence the sun has on the polar light show.

The aurora on Jupiter are hundreds of times more energetic than those seen on Earth and occur ceaselessly. On Earth aurora are often fleeting and have become a prized tourist attraction in countries around the North Pole.

While on Earth aurora are caused by solar storms – when highly energetic particles ejected by the sun collide with atoms in our atmosphere to release light – Jupiter’s aurora are also caused by other sources.

The strong magnetic field of the gas giant, which extends up to two million miles from the planet, captures charged particles from its surrounding environment, accelerating them towards the poles.

Debris thrown into space by the volcanoes on one of Jupiter’s moons, Io, is also responsible for causing these aurora.

Full report: Hubble captures mysterious aurora the size of EARTH over Jupiter’s north pole | Daily Mail Online
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