Juno jupiter polar

NASA's Juno spacecraft revealed for the first time Jupiter's poles, featuring cyclone storms and intense auroras never seen before.

About this subject

NASA's Juno mission, launched in 2011 and inserted into Jupiter's orbit in July 2016, was designed to study the gas giant's composition, gravitational field, and magnetosphere. Unlike previous missions that observed Jupiter from equatorial or mid-latitudes, Juno adopted a highly elliptical polar orbit, passing as close as 4,200 km above the cloud tops. This trajectory allowed the first detailed images of Jupiter's polar regions, areas that had remained a mystery.

Data from Juno revealed that each of Jupiter's poles is dominated by a cluster of giant cyclones. At the north pole, a central cyclone is surrounded by eight cyclones arranged in an octagonal pattern, while the south pole has a central cyclone encircled by five cyclones in a pentagonal arrangement. These storms have diameters reaching 4,000 km and winds exceeding 350 km/h. Additionally, Juno detected intense ultraviolet auroras at the poles, much more energetic than Earth's, generated by the interaction of Jupiter's magnetic field with charged particles from the Sun and its moon Io.

Juno's discoveries also include evidence that Jupiter's core is diffuse rather than compact, and that the planet's magnetic field is more complex than previously thought. The mission is scheduled to continue until September 2025, when it will perform a controlled deorbit to avoid contaminating the moons Europa and Ganymede. Studying Jupiter's poles helps scientists understand atmospheric dynamics on giant planets, including exoplanets.

Frequently Asked Questions

Why was Juno placed in a polar orbit around Jupiter?

The polar orbit allows Juno to fly directly over Jupiter's poles, regions never before photographed in detail. This trajectory also minimizes exposure to the planet's intense radiation and enables precise measurements of its gravitational and magnetic fields.

What did Juno discover at Jupiter's poles?

Juno discovered clusters of giant cyclones at both poles, with distinct geometric patterns (octagonal in the north and pentagonal in the south). It also detected extremely energetic polar auroras and anomalies in the magnetic field.

How long will the Juno mission last?

Juno's primary mission was completed in 2021, but it was extended until September 2025. After that, the spacecraft will be deliberately deorbited into Jupiter to avoid contaminating its icy moons.