Physical astronomers have detected a heat wave the size of 10 Earths propagating through Jupiter’s atmosphere.
It was 130,000 kilometers (about 81,000 miles) wide, and 700 degrees Celsius (1,292 degrees Fahrenheit), traveling at up to 2,400 meters per second away from the Jovian North Pole.
The team of scientists who presented their findings at the Europlanet Science Conference say the discovery could solve one of the most vexing mysteries about the largest planet in our solar system – why it’s so much hotter than models predict.
They point out that it’s the perpetual auroras shining at Jupiter’s poles that could provide additional energy to heat the gas giant to temperatures well beyond what we’d expect — and most likely, combined with intense solar winds, are responsible for the surging heat wave.
“Last year, we produced… the first maps of Jupiter’s upper atmosphere able to identify the sources of the prevailing heat”… Thanks to these maps, we showed that the aurora borealis To Jupiter was a possible mechanism that could explain these temperatures.”
The first idea that something strange was happening in Jupiter’s atmosphere was in the 1970s, about 50 years ago.
Jupiter is much farther from the sun than Earth; Almost five times the distance, in fact. From that distance, it receives only four percent of the solar radiation that reaches Earth.
The average upper atmosphere temperature should be around -73°C (-99°F). Instead, it lies at about 420 degrees Celsius – comparable to Earth’s upper atmosphere, much higher than can be explained by solar heating alone.
That means there must be something else going on at Jupiter, and the first heat maps, obtained by O’Donoghue and his colleagues and published last year, suggest a solution.
And Jupiter is crowned with the strongest aurora borealis in the solar system, glowing in wavelengths invisible to the human eye. We also know that the aurora borealis here on Earth causes significant heating of our atmosphere.
Jupiter’s auroras are much like Earth’s auroras: an interaction between charged particles, magnetic fields, and particles in the planet’s atmosphere. They are also very alien. The aurora borealis on Earth are generated by the blowing of particles from the strong solar wind. It’s discontinuous, and it depends on those irregular inputs.
Jupiter’s aurora borealis are permanent, generated by particles from its moon Io, the most volcanic body in the Solar System, which constantly causes sulfur dioxide to erupt. This forms a hoop of plasma around Jupiter, which is directed to its poles through magnetic field lines, where it rains into the atmosphere.
And voila – the aurora borealis. Previous heat maps of Jupiter have revealed hot spots just below the auroral oval, suggesting a link between the two.
But then it got more interesting. Io’s contribution does not mean that there is no auroral contribution from the Sun, and this is what O’Donoghue and colleagues have observed.
As they were collecting observations of Jupiter and strange temperatures, a dense solar wind collided with the gas giant. As a result, the team noticed an improvement in the auroral heat.
As the hot gas expands, this is likely what sent the heat wave leaking out of the auroral oval and rolling toward the equator at thousands of kilometers per hour.
Therefore, during its spread, it could have caused the atmosphere to heat up by a significant amount.
“While the aurora borealis continually transmits heat to the rest of the planet, these heat wave events represent an important additional source of energy”…These findings add to our knowledge of weather and climate in Jupiter’s upper atmosphere, and are a huge help in trying to solve The problem of ‘energy crisis’ plaguing research on giant planets.
And Jupiter isn’t the only planet in the solar system that’s hotter than it should be. Saturn, Neptune, and Uranus are hundreds of degrees hotter than solar heating can explain.
And while none of the others have Jupiter-scale auroras, this discovery represents an avenue of exploration that might go some way toward solving the mystery.