Astronomers have long believed that Jupiter's upper clouds, which form the planet's iconic light brown bands, are made of frozen ammonia. But new research shows that these clouds are actually lower in the atmosphere than we thought, and are made of ammonium bisulfide mixed with smog.
Hubble's photos of Jupiter show an ever-changing landscape due to its turbulent atmosphere. Image credits: NASA / ESA / Hubble / Amy Simon, NASA Goddard Space Flight Center / Michael H. Wong, University of California, Berkeley / Joseph DePasquale, STScI.
Citizen scientist Steve Hill has previously shown that it is possible to map a planet's atmosphere using just a special colored filter and a backyard telescope.
These results provided the first clue that the clouds are too deep in Jupiter's warm atmosphere to match clouds made of ammonia ice.
To find out, Hill and a team of professional astronomers from the University of Oxford, the University of Leicester and the British Astronomical Society used the MUSE instrument on ESO's Very Large Telescope (VLT) to study the atmospheres of gas giant planets. did.
“MUSE will be able to scan Jupiter's atmosphere at different wavelengths and map the different molecules that make up Jupiter's atmosphere,” they said.
Their study shows that a new approach using backyard telescopes or VLT/MUSE can map the abundance of ammonia in Jupiter's atmosphere with remarkable accuracy.
In terms of clouds, they concluded that Jupiter's atmosphere closely resembles a layered cake.
A cloud of ammonium hydrosulfide covers the upper layer, but decorations of ammonia ice clouds carried to the top by strong vertical convection can also be seen.
However, the overall structure of the cake is still not fully understood, and the work of citizen scientists may be the key to figuring it out.
So the next time you gaze at Jupiter or Saturn from your backyard, you just might be uncovering some hidden secrets in our solar system.
“We tested the reliability of the filter imaging technique by applying it to VLT/MUSE observations of Jupiter and found that the method closely matches more sophisticated analyzes of these observations and is also consistent with observations of Jupiter.” We have shown that the microwave wavelengths studied by NASA's Juno spacecraft and the Super Large Array yield surprisingly reliable results,” the astronomers said.
“We show that the main reflection level at red wavelengths is at the 2-3 bar level, which is much lower than the expected ammonia ice cloud condensation level of 0.7 bar, and the ammonia We conclude that ice cannot be the main cloud component.”
“We also showed that the same technique can be applied to MUSE observations of Saturn, where extracted ammonia maps were measured by NASA's Cassini spacecraft and the NASA/ESA/CSA James Webb Space Telescope at pressures greater than 2 We found a very good agreement with the ammonia abundance.
of findings will appear in Geophysical Research Journal: Planets.
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Patrick G.J. Irwin others. 2025. Clouds and ammonia in the atmospheres of Jupiter and Saturn are determined from band depth analysis of VLT/MUSE observations. JGR Planets 130 (1): e2024JE008622;doi: 10.1029/2024JE008622
Source: www.sci.news
