Les profondeurs de l’atmosphère de Jupiter
Dans le dernier épisode de L’Élement, le conseiller scientifique Jesse Rogerson, explique ce que le nouvelle données de l'astronef Juno indiquent a propos de l’atmosphère de Jupiter.
The Juno Spacecraft has been orbiting Jupiter since mid-2016 and has sent back some of the most stunning pictures of the planet we’ve ever seen.
One of the most iconic features of Jupiter’s atmosphere is its differently-coloured belts and zones, stretching horizontally across the planet. The dark belt regions are sinking gas, while lighter areas are rising. They are separated by jet streams moving either east or west, at speeds of nearly 500 km/h. Along with a multitude of cyclones and eddies, these bands represent the most visible part of what is known as ‘the weather layer’ on Jupiter. But how deep does that weather go?
New data from Juno has found that these bands of moving gas go as deep as 3,000 km into the atmosphere of Jupiter - much deeper than expected. That means that as much as 1 percent of Jupiter’s mass is part of the Weather Layer on Jupiter. For comparison, Earth's weather layer, our atmosphere, makes up one millionth a percent of Earth’s mass.
Juno has also been studying the poles of Jupiter very closely. It has found that both poles have a massive central cyclone, surrounded by multiple smaller cyclonic storms. And they’re so densely packed, the storms are basically rubbing up against each other; which leaves atmospheric scientists wondering, why don’t they merge, or get torn apart?
As often is the case in science, better instruments tend to lead to more questions. Juno still has about six months left in its primary mission; lots of time to find more clues to understanding the Jovian atmosphere.