NASA’s Juno spacecraft has been orbiting Jupiter since 2016, unlocking new mysteries about the Solar System’s largest planet.
From violent cyclones to a surprisingly diffuse core, Juno’s findings challenge long-held assumptions and offer a deeper understanding of Jupiter’s formation and evolution.
Each new discovery pushes the limits of planetary science, offering insights that could change our view of gas giants and planetary systems across the universe.
What is the Juno Mission?
The Juno mission is a solar-powered spacecraft designed to study Jupiter’s atmosphere, magnetic field, and internal structure. Equipped with a range of scientific instruments, including a microwave radiometer, magnetometers, and high-resolution cameras, Juno provides critical data about the planet’s atmosphere and composition.
To protect its sensitive electronics from Jupiter’s intense radiation, Juno is housed in a durable titanium radiation vault and powered by large solar arrays, making it the first solar-powered spacecraft to venture so far from the Sun.
Cyclones Larger Than Earth
One of Juno’s most remarkable discoveries is the presence of massive cyclones at Jupiter’s poles. These cyclones, some of which are larger than Earth, form in stable, polygonal arrangements—eight in the north and five in the south.
Unlike the transient storms on Earth, Jupiter’s polar cyclones remain in the same locations for extended periods, revealing a dynamic and complex atmospheric system unlike anything observed on our planet.
The discovery of these persistent cyclones challenges our understanding of planetary weather and storm formation.
The Depth of the Great Red Spot
Juno has also provided unprecedented insights into Jupiter’s famous Great Red Spot. This massive storm has been raging for centuries, but Juno’s data reveals that it extends approximately 300 miles into the planet’s atmosphere—much deeper than previously known.
Earlier observations only allowed scientists to study the storm’s surface features, but Juno’s detailed measurements give us a new understanding of the energy processes driving this colossal storm, offering valuable insights into the planet’s atmospheric dynamics.
A Fuzzy Core: A Surprising Revelation
Perhaps the most unexpected discovery from the Juno mission is the nature of Jupiter’s core. Contrary to previous models that suggested a dense, solid core, Juno’s gravity measurements show that Jupiter’s core is actually diffuse, or “fuzzy.”
This means it consists of heavy elements that gradually transition into the surrounding layers of metallic hydrogen.
This finding upends existing models of Jupiter’s interior and challenges long-standing assumptions about planetary structure, offering a new perspective on the gas giant’s formation.
Clues to Jupiter’s Violent Past
The diffuse nature of Jupiter’s core raises fascinating questions about the planet’s early history. One hypothesis suggests that a massive collision with another planetary body early in Jupiter’s formation could have disrupted its interior, leading to the current “fuzzy” structure.
If true, this could mean that Jupiter’s violent past played a pivotal role in shaping its present-day characteristics, offering scientists a new way to think about the planet’s evolution.
Implications for Planetary Science
Juno’s discoveries extend beyond just Jupiter, with significant implications for broader planetary science. The finding of deep, stable cyclones and a diffuse core forces scientists to rethink existing models of gas giants’ atmospheres and internal structures.
These revelations could reshape our understanding of how gas giants form and evolve, providing new theories that could be applied to other planets in our solar system and beyond.
