The atmospheres of Jupiter and Saturn are known for colorful swirls known as jets, which have fascinated and puzzled astronomers for decades. They are incredibly strong and have lasted for centuries. Finally, we can recreate them in the lab.
University of California, Los Angeles (UCLA) professor Jonathan Aurnou and collaborators in France first used a computer simulation to recreate two possible scenarios – one with a shallow jet stream and one with jets extending deep down into the molecular envelope of Jupiter. Their breakthrough, reported in Nature Physics, was to be able to have a real model of the deep jets in the lab.
"We can make these features in a computer, but we couldn’t make them happen in a lab,” said Aurnou in a statement. “If we have a theoretical understanding of a system, we should be able to create an analog model.”
The team was not only able to recreate the model, but they also showed that the deep jets can last for a very long time at high latitudes and they are not affected by the friction within the fluid.
To make this test, the researchers used a state-of-the-art spinning table and a garbage can full of water that was positioned at its center. It was spun at about 75 revolutions per minute, which pushed the water on the side of the can, forming a parabola – a good proxy for Jupiter’s curved atmosphere.
The streams were reproduced by introducing flows of water with inlets and outlets in the bottom of the can. The flows generated turbulence within the water, and in minutes six concentric circular streams appeared, perfectly mimicking what has been observed on the gas giant.
“This is the first time that anyone has demonstrated that strong jets that look like those on Jupiter can develop in a real fluid,” Aurnou added.
The ability to reproduce the Jovian atmosphere will come in handy very soon, as more data comes from the Juno spacecraft that is studying the atmosphere. Last year, astronomers discovered that ammonia, the main component of the clouds, moves to deeper layers than previously thought, which means our understanding of Jupiter might have to be adapted. /
