Planetary-scale giant storms erupt on Saturn periodically. There have been at least six recorded occurrences of past eruptions, and the most recent one was in 2010, with its whole life span captured by NASA’s Cassini mission. To find out more about these megastorms, University of California, Berkeley’s Professor Imke de Pater and her colleagues had to probe layers in the Saturnian atmosphere below the clouds, which are invisible to the human eye. That’s why the astronomers turned to NSF’s Karl G. Jansky Very Large Array (VLA).
Every 20 to 30 years, a giant storm erupts on Saturn, creating enormous cloud disturbances with a clear head marching forward until it wraps around the whole planet.
The most recent eruption was in 2010, with visible cloud activities lasting for more than 6 months.
At that time, NASA’s Cassini spacecraft was still orbiting Saturn and the on-board instruments, including the visible camera, radio instruments, infrared camera, and radar, returned exquisite details of the astronomical feast.
The next event is expected to happen within 10 to 20 years, based on prior statistics and the understanding of the storm dynamics.
In 2015, Professor de Pater and co-authors used VLA to probe the deep response of Saturn’s atmosphere to the giant storms.
In addition to the remnant effect of the storm in 2010, they found long-lasting signatures of all mid-latitude giant storms, a mixture of equatorial storms up to hundreds of years old, and potentially an unreported older storm at 70°N.
“At radio wavelengths, we probe below the visible cloud layers on giant planets,” Professor de Pater said.
“Since chemical reactions and dynamics will alter the composition of a planet’s atmosphere, observations below these cloud layers are required to constrain the planet’s true atmospheric composition, a key parameter for planet formation models.”
“Radio observations help characterize dynamical, physical, and chemical processes including heat…
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