Planetary scientists first became aware of the connection between Earth and Jupiter in 2018, when they noticed striking similarities in images of Jupiter's giant cyclones and turbulent ocean currents. In 2022, they Analyzed High-resolution infrared image of a cyclone on Jupiter taken by NASA's Juno spacecraft. Analysis reveals that a type of convection similar to that seen on Earth helps sustain Jupiter's storms, which can be thousands of miles wide and last for years. The 2022 study focused directly on Jupiter's cyclones, but the authors also saw thin tendrils called filaments in the spaces between the vortices of gas. These filaments have analogues on Earth, and the authors used Juno's detailed images to study whether this similarity to Earth's oceanic and atmospheric processes is merely superficial.
This composite image, created from data collected by the JIRAM instrument on NASA's Juno spacecraft, shows a central cyclone at Jupiter's north pole and eight surrounding cyclones. JIRAM collects data in infrared, and the colors in this composite represent radiated heat. The yellow (thinnest) clouds have a brightness temperature of about -9 degrees Fahrenheit (-13 degrees Celsius), while the dark red (thickest) clouds have a brightness temperature of about -181 degrees Fahrenheit (83 degrees Celsius). Image credit: NASA / JPL-Caltech / SwRI / ASI / INAF / JIRAM.
Fronts are often featured in weather forecasts (for example, cold fronts and storm fronts) and apply to both gases and liquids.
A front is a boundary between masses of gas or liquid that have different densities due to differences in properties such as temperature.
In the ocean, fronts can also form due to differences in salinity, which, along with temperature, affects the density of seawater.
The main characteristic of a front is that its leading edge is characterized by strong vertical speed and can generate wind and currents.
To understand the role of the filaments clearly visible during Jupiter's cyclones in the Juno images, Dr. Leah Siegelman of the Scripps Institution of Oceanography and Dr. Patrice Klein of the California Institute of Technology examined a series of infrared images from Juno.
The series of images was taken 30 seconds apart of Jupiter's north polar region.
Because the images were taken in infrared, the team was able to calculate the temperature, finding that brighter areas were warmer and darker areas were cooler.
On Jupiter, the hotter parts of the atmosphere correspond to thin clouds, while the cooler parts are covered by thicker clouds that block more of the heat emanating from Jupiter's superheated core.
The researchers then tracked the movement of the clouds and filaments over the 30-second intervals between photos to calculate horizontal wind speeds.
These two pieces of information allowed the scientists to apply methods from ocean and atmospheric science to Jupiter to calculate vertical wind speeds that correspond to the temperatures and horizontal wind speeds the researchers derived from the images.
Calculating vertical wind speeds, they found that Jupiter's filaments do in fact move like Earth's fronts.
The vertical wind speeds at the edges of Jupiter's fronts also mean that the fronts transport energy in the form of heat from the planet's hot interior to the upper atmosphere, potentially generating large cyclones.
Although convection is the primary driving force, fronts account for a quarter of the total kinetic energy powering Jupiter's cyclones and 40 percent of the vertical heat transport.
“These cyclones at Jupiter's poles have continued since they were first observed in 2016,” Dr Siegelman said.
“These filaments between the larger vortices are relatively small, but they are a key mechanism for maintaining cyclones.”
“It's intriguing that fronts and convection exist and influence Earth and Jupiter, suggesting that these processes may also exist on other turbulent fluid bodies in the universe.”
“Jupiter's enormous scale and Juno's high-resolution images allow us to more clearly visualize how small-scale phenomena like fronts connect with larger-scale phenomena like cyclones and the atmosphere. These connections are often difficult to observe on Earth because they are much smaller and more ephemeral.”
“But the long-awaited new satellite, SWOT, will make observing these ocean phenomena much easier.”
“There's a kind of cosmic beauty in knowing that these physical mechanisms on Earth exist on other planets far, far away.”
Team paper Published in the journal Natural Physics.
_____
L. Siegelman & P. Klein. Frontogenesis at high latitudes on Jupiter. National Physical SocietyPublished online June 6, 2024; doi: 10.1038/s41567-024-02516-x
Source: www.sci.news
