Saturn's 100-year "giant storms" are creating radio signals that scientists can't fully explain

Imagine a thunderstorm so massive that its dark outline wraps around the entire planet.

Such terrifying “mega storms” are spreading Saturn. Also called the Great White Spots, they erupt once every 20 or 30 years in the northern hemisphere of the planet and erupt non-stop for months. Astronomers have observed six of these planet-wide storms orbiting Saturn since 1876. Most of them The last storm hit in December 2010when NASA’s Cassini spacecraft happened to be orbiting the planet, capturing a front row view of the entire 200-day lifetime of the giant storm.

Now, new research on the epic 2010 storm finds that 200 days of thunder were just a few drops in a much larger and more bizarre meteorological bucket. According to a recent radio telescope survey, the lingering effects of massive storms that raged on Saturn more than 100 years ago are still visible in the planet’s atmosphere today, leaving behind persistent chemical anomalies that scientists can’t fully explain.

In other words, long after the giant storm has disappeared from view, its impact on Saturn’s weather will last for centuries.

“Most of the time, Saturn’s atmosphere appears hazy and featureless to the naked eye Jupiter“A Colorful and Vibrant Atmosphere,” the researchers wrote in a study published August 11 in the journal A Colorful, Vibrant Atmosphere. Science advances. “This picture changes when we look at Saturn with a radio eye.”

Related: Strange radio signals detected from an Earth-like planet could be a magnetic field essential to life

A radio image of Saturn was taken with the VLA in May 2015, with brighter radio emissions from Saturn and its rings subtracted. Because ammonia blocks radio waves, bright features indicate regions where ammonia is depleted and the VLA can see deeper into the atmosphere. (Image credit: RJ Sault and I. de Pater)

Using the Very Large Array radio telescope in New Mexico, the study authors peered through the haze of Saturn’s upper atmosphere, hoping to find chemical remnants of the massive 2010 storm. In fact, the team found traces of all six massive storms on record, which hit the closest one in more than 130 years, as well as a possible new storm not previously recorded.

visible only in radio wavelengthsThose remnants took on a large shape ammonia anomaly. Saturn’s upper cloud layer is composed primarily of ammonia ice clouds. But in their radio observations, the researchers saw areas of unexpectedly low concentrations of ammonia below this cloud layer in regions associated with past storms. Meanwhile, ammonia concentrations rose far above normal, hundreds of miles below these atmospheric regions.

The implication, according to the study’s authors, is that massive storms seem to be pushing some mysterious ammonia transport that pulls ammonia from Saturn’s upper atmosphere into the depths of the lower atmosphere—perhaps in the form of “soft ball” rain in which icy hail is present. Balls of ammonia fall into the atmosphere before evaporating again. This soft process, the researchers wrote, appears to continue for hundreds of years after the storm has apparently cleared.

While the mechanisms behind these atmospheric anomalies—and behind Saturn’s giant storms in general—remain a mystery, studying them further could expand not only our understanding of how giant planets form but also of what drives storm systems like Saturn’s Great White Spots. and Jupiter the largest. big red spot to grow inexplicably large, according to the researchers.

Learn about the mechanisms of the largest storms in the region Solar System It puts hurricane theory into a broader cosmic context, challenges our current knowledge and pushes the boundaries of terrestrial meteorology,” lead study author Cheng Liformerly at the University of California, Berkeley and now an assistant professor at the University of Michigan, said in a statement.