A planetary similarity

Study: Driving force of huge cyclones on Jupiter not all that different than Earth

SAN DIEGO — Shortly after entering orbit around Jupiter in 2016, the spacecraft Juno captured images of huge cyclones whirling in geometric patterns at the planet’s poles, an unexpected finding that dazzled scientists.

Jupiter’s poles cannot be clearly seen from Earth. The existence of the cyclones were discovered when Juno became the first probe to go into polar orbit around the gaseous giant.

A new study led by University of California San Diego reveals another surprise: The cyclones are sustained by moist convection, the term for water vapor that rises and turns into a cloud. It’s very similar to the process that feeds cyclones on Earth, a starkly different world.

Earth has land. Jupiter does not. Earth has oceans composed of water. Jupiter has what scientists describe as a large ocean composed of hydrogen.

Even so, “The turbulence we see on Jupiter looks just like what we see here,” said Lia Siegelman, a postdoctoral researcher at UC San Diego’s Scripps Institution of Oceanography. She is the lead author on a Jan. 10 paper in the journal Nature Physics that describes the phenomenon.

The finding arose, in part, from serendipity.

Siegelman is a physical oceanographer who did graduate work at Caltech, where her office was close to that of Andrew Ingersoll, a prominent planetary scientist who had received polar data from Juno. He shared it with Siegelman, who noticed similarities between the cyclones on Jupiter and those she had studied in Earth’s Southern Ocean, the body of water that surrounds Antarctica. That led to collaboration with many scientists and the new paper in Nature Physics.

It also led to a sense of awe for Siegelman, who told the San Diego Union-Tribune, “It’s quite fascinating to see something like this on a planet that is so far away.”

Jupiter is currently more than 530 million miles from Earth.