Saturn’s rings heat its atmosphere Northwest and national news

By Dean Murray via Coins

A new study revealed that Saturn’s rings heat its atmosphere.

Scientists announced the discovery on March 30, which they said had never been seen before in our solar system.

A NASA spokesperson said: “The secret has been hiding in plain sight for 40 years. But it took the foresight of a veteran astronomer to piece it together within a year, using Saturn observations from NASA’s Hubble Space Telescope and the retired Cassini probe, as well as the Voyager 1 and spacecraft. 2 and a retired International UV Explorer mission.

Discovery: Saturn’s vast ring system heats the giant airplaneupper atmosphere. This phenomenon has never been seen before in the solar system. It’s an unexpected interaction between Saturn and its rings that likely provides a tool for predicting whether planets around other stars have Saturn-like ring systems as well. “

The clear evidence, scientists say, is an excess of ultraviolet radiation, which is seen as a spectral line from hot hydrogen in Saturn’s atmosphere.

NASA said: “The radiation plume means that something is polluting the upper atmosphere and heating it up from the outside.

“A more plausible explanation is that ring-ice particles raining down on Saturn’s atmosphere cause this heating. This could be due to the impact of micrometeorites, particle bombardment of the solar wind, solar ultraviolet radiation, or electromagnetic forces picking up electrically charged dust.

“All of this happens under the influence of Saturn’s gravitational field that pulls particles into the planet. When NASA’s Cassini probe plunged into Saturn’s atmosphere at the end of its mission in 2017, it measured the composition of the atmosphere and confirmed that many particles were falling from the rings.”

Lotfi Ben Jaffel of the Astrophysical Institute in Paris and the University of Arizona’s Lunar and Planetary Laboratory and author of a paper published March 30 in Planetary Science Journal.

Ben Javel said: “Although the slow disintegration of the rings is well known, its effect on the atomic hydrogen of the planet is a surprise. From the Cassini probe, we already knew about the effect of the rings. However, we did not know anything about their atomic hydrogen content.

“It’s all driven by ring particles cascading into the atmosphere at specific latitudes. They modify the upper atmosphere, they change the composition. And then you also have collisions with atmospheric gases that potentially heat the atmosphere at a certain altitude.”

Ben Javel’s conclusion required compiling archival ultraviolet observations from four space missions that studied Saturn. This includes observations from NASA’s two Voyager probes that flew by Saturn in the 1980s and measured the excess ultraviolet radiation. At the time, astronomers dismissed the measurements as noise in the detectors.

The Cassini mission, which arrived at Saturn in 2004, collected ultraviolet data on the atmosphere (over several years). Additional data came from Hubble and the International Ultraviolet Explorer, launched in 1978, which was an international collaboration between NASA, the European Space Agency (ESA), and the UK Science and Engineering Research Council.

NASA said the long-awaited question is whether all the data is deceptive, or whether it reflects a real phenomenon on Saturn.

The space agency wrote: “The key to assembling the jigsaw puzzle came in Ben Javel’s decision to use measurements from the Hubble Space Telescope Imaging Spectroradiometer (STIS). His careful observations of Saturn were used to calibrate archival UV data from all four other space missions that have observed Saturn. Compare STIS observations of Saturn’s ultraviolet light distribution between several space missions and instruments.”

“When everything was calibrated, we clearly saw that the spectra were consistent across all missions,” said Lotfi Ben Javel. “This was possible because we had the same reference point, from Hubble, on the rate of energy transfer from the atmosphere as measured over decades.

“It really came as a surprise to me. I just plotted the different light distribution data together, and then I realized, wow — it’s the same thing.”

Four decades of UV data covering multiple solar cycles helps astronomers study the sun’s seasonal effects on Saturn. By bringing all the various data together and calibrating them, Ben Javel found that there was no difference in the level of UV radiation.

“At any time and anywhere on the planet, we can follow the level of ultraviolet radiation,” he said. This points to the constant “ice rain” from Saturn’s rings as the best explanation.

Ben Javel continues: “We are only at the beginning of the impact of this circular characterization on the planet’s upper atmosphere. We eventually want to have a global approach that would yield a true atmospheric signature on distant worlds. One of the goals of this study is to see how we can apply it on planets orbiting other stars, called the search for “outer rings”.