Located some 500 million miles from the sun, Jupiter should be bitterly cold. But, mysteriously, some parts of the planet’s upper atmosphere are hundreds or even thousands of degrees hotter than they should be.
Scientists finally found a possible reason: Wild winds from Jupiter’s famed Giant Red Spot — the biggest storm in the solar system that’s actually larger than the Earth itself — may be fueling the unusual heating of the massive planet’s atmosphere.
The new study, published Wednesday in the peer-reviewed British journal Nature, concludes the storm produces energy waves that dramatically turn up the heat in the far reaches of Jupiter’s atmosphere.
Over five times more distant from the sun than Earth, Jupiter’s warm upper atmosphere has long puzzled scientists. Temperatures there range from 800 to 1,700 degrees. And above the Red Spot, it’s even hotter — a sizzling 2,500 degrees, said Boston University’s James O’Donoghue, the study’s lead author.
That level of heat is similar to Earth’s upper atmosphere and far hotter than any outer planets. Theoretically, sunlight should only be able to heat Jupiter’s upper atmosphere to a not-so-balmy 100 degrees below zero. Jupiter only receives 3.3% of the light — and therefore heating — that Earth does, he said.
Using an infrared telescope in Hawaii, O’Donoghue and other researchers scanned Jupiter’s upper atmosphere.
“We could see almost immediately that our maximum temperatures at high altitudes were above the Great Red Spot far below — a weird coincidence or a major clue?” O’Donoghue wondered. It was more than a coincidence, he theorized.
Jupiter’s Red Spot is one of the greatest marvels of our solar system. Discovered centuries ago, its swirling pattern of colorful gases is often called a “perpetual hurricane.” O’Donoghue said the giant storm could be sending some combination of gravity and acoustic waves upwards.
Similar to how a guitar string moves when plucked, gravity waves are created when air currents collide with objects like mountains. Sound waves are compressions of the air. A combination of these two wave types “crashing” like ocean waves on a beach warms the upper atmosphere 500 miles above the storm, the study found.
NASA’s spacecraft Juno, now in orbit around Jupiter, should help scientists learn more about the spot and its heating element.
“We’re not sure how deep the storm goes, so hopefully Juno will give us a closer look at that,” O’Donoghue said. “Juno and ground-based work will complement each other, giving us a complete top-down view of the spot to understand what keeps it ticking.”