The planet Saturn is easily recognizable by its magnificent ring system, which can be easily seen with a small telescope. Now astronomers have discovered that the rings are not as calm as they seem. Particles of the icy rings fall into Saturn’s atmosphere. This heats the upper atmosphere. To reach this conclusion, a collection of 40 years of Saturn observation data collected by NASA during the four planet missions was needed. Observations from the Hubble Space Telescope were used to consolidate all the evidence gathered in ultraviolet light. These results can be applied to determine whether similar ring systems surround planets orbiting other stars. Its rings may be too far to see, but ultraviolet spectroscopy of the planets can provide clues.

The secret was hidden from view for 40 years. But it took the insight of an experienced astronomer to put it all together over the course of a year using observations of Saturn from NASA’s Hubble Space Telescope and the decommissioned Cassini probe, as well as the Voyager 1 and 2 spacecraft and the defunct International Ultraviolet. Explorer mission.

Discovery: Saturn’s large ring system is warming the giant planet’s upper atmosphere. This phenomenon had never been observed before in the solar system. This is an unexpected interaction between Saturn and its rings, and could potentially be a tool to predict whether planets around other stars also have extraordinary Saturn-like ring systems.

One provable evidence is the excess of ultraviolet radiation in Saturn’s atmosphere, which can be seen as a spectral hot hydrogen line. Rising radiation means that something is polluting and heating the upper atmosphere from the outside.

The most likely explanation is that ice ring particles falling into Saturn’s atmosphere caused this warming. This could be the result of micrometeorite impacts, solar wind particle bombardment, solar ultraviolet radiation, or electromagnetic forces picking up electrically charged dust. All this happens under the influence of Saturn’s gravitational field, which attracts particles to 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 had fallen from the rings.

“Although the slow decay of the rings is well known, the effect on the planet’s atomic hydrogen is surprising. We already knew the effects of the rings from the Cassini probe. Lotfi Ben-Jaffel of the Paris Astrophysics Institute and the University of Arizona’s Lunar Planetary Laboratory,” author of the paper, published March 30 in the journal Planetary Science, said. But we didn’t know anything about the atomic hydrogen content,” he said. Daily.

Forty years of UV data cover several solar cycles and help astronomers study the Sun’s seasonal influence on Saturn. By combining and calibrating all the various data, Ben-Jaffel found that there was no difference in the level of UV radiation. “We can monitor the level of UV radiation anywhere on the planet, at any time,” he said. This points to a constant “ice shower” from Saturn’s rings as the best explanation.

“We are just at the beginning of this impact of the ring on the upper layers of the planet’s atmosphere. Ultimately, we want to have a global approach that will yield real insights into the atmospheres of distant worlds. One of the goals of this research is to see how we can apply it to planets orbiting other stars. Call it an exoring search.