Amazing Discoveries From Jupiter
The Largest Magnetic Sphere in the Solar System
Earth’s magnetic field originates from swirling molten iron in its core, generating a dynamo effect. On Jupiter, however, the magnetic field is powered by an intriguing form of matter known as metallic hydrogen.
Jupiter’s massive size creates immense pressures deep within its core, producing exotic matter found nowhere else in the solar system. Hydrogen, typically a gas and the lightest element on the periodic table, is compressed within the planet until its electrons detach from the atoms and move freely. This sea of mobile electrons forms the dynamo that generates Jupiter’s powerful magnetic field. Jupiter’s magnetic sphere is the largest object in the solar system, several times wider than the sun. This vast magnetosphere shields the planet from solar winds, deflecting particles as far as Saturn’s orbit.
While Jupiter is protected from solar winds, the Jovian system—comprising Jupiter and its moons—produces its own energetic particles. These particles are trapped and accelerated by the very magnetic field that shields the planet from external ionic bombardment.
The charged particles originate from Jupiter’s most volatile moon, Io, whose volcanic eruptions become electrified as the magnetic field strips electrons from its molecules. These stray electrons zip around Jupiter at near light speed, releasing radio waves. From a scientific perspective, these radio emissions are problematic because they drown out radar signals used to probe the planet’s interior from Earth. Additionally, the electron shield creates a radiation belt that bombards visiting spacecraft. To mitigate this hazard, scientists had to build the probe that collected these readings “like an armored tank,”, according to Heidi Becker, a NASA planetary scientist and one of the 2017 Juno missions co-investigative leads. All the spacecrafts sensitive electronics were housed inside an electron-shielding titanium vault weighing almost 400 pounds.
Despite the challenges, Jupiter’s powerful magnetosphere creates spectacular auroras when the electrons it directs collide with other atoms in the atmosphere, releasing bursts of light. Given that the magnetic field is large enough to envelop the moons, it also transports ejecta from Io to other locations. Scientists have detected contaminants as far away as Europa, another of Jupiter’s moons located hundreds of thousands of miles from Io.
Jupiter is Too Hot
Jupiter continues to radiate heat from its primordial days. This residual heat drives the intense storms that dominate Jupiter’s atmosphere.
The Voyager mission measured Jupiter’s heat output when it passed the gas giant in 1979. Scientists discovered that Jupiter emitted more heat than models had predicted, with some areas burning at nearly 800 degrees Fahrenheit above expectations.
Four decades later, scientists at the Keck Observatory resolved the mystery of Jupiter’s heat distribution. They mapped the planet’s temperatures, finding it coldest near the equator and hottest near the magnetic poles, where auroras flare most intensely. This revealed that auroras are an additional heat source. Plasma from Io’s volcanic eruption collides with Jupiter’s atmosphere to create spectacular auroras, and it interacts with Jupiter’s fast-moving winds, generating enough friction to raise global temperatures.
Also, did you know that Jupiter actually has a ring?
