Saturn’s rings are disappearing, and we don’t know how long they will last.
Astronomers have known this since the 1980s SaturnThe inner ice ring continues to erode in the upper atmosphere. Torrential rains occur at speeds as high as Olympic puddles Is raining On the gas giant every day. However, how fast is Iconic ring system It shrinks—what determines when it will disappear—remains an open question.
Fortunately, the mighty NASA The James Webb Space Telescope (JWST or Webb), whose powerful instruments have hitherto shot up the most distant galaxies of the early universe, will soon be investigating an interesting phenomenon found much closer to home.
“We’re still trying to figure out how quickly they erode,” said James O’Donoghue, a planetary scientist with the Japan Aerospace Exploration Agency who will lead a new effort to determine how long Saturn’s rings will last. statement (Opens in a new tab) Posted on Monday (17/4). “Right now, research shows that the rings will only be part of Saturn for another few hundred million years.”
Related: Saturn: everything you need to know about the sixth planet from the sun
To better estimate the age of Saturn’s iconic rings, JWST and the Keck Observatory in Hawaii will be part of a long-term observation campaign to study the planet. The telescope will help monitor how the “ring rain” fluctuates during a full season on the gas giant, which lasts about seven Earth years thanks to its orbit far from the sun.
Astronomers expect interesting data from the campaign, as previous studies have shown that large amounts of ring material are constantly falling on Saturn. For example, data sent home from NASA Cassini The spacecraft – which flew right through the gap between Saturn and its rings 22 times when it crashed into the planet in 2017 – revealed that between 880 pounds (400 kg) and 6,000 pounds (2,800 kg) of hail fell on Earth. planet every second and upper atmosphere heating.
At this rate, the episode is possible disappear In about 300 million years. While this may seem remote, the flood directs the symbolic ring system to “Relatively quick deathOn cosmic time scales, however, the rate of deposition of ring material on this planet is still highly uncertain; the rings could disappear as quickly as 100 million years, or they could remain suspended for 1.1 billion years, astronomers say.
“Right now we only have one very broad estimate,” O’Donoghue told Space.com Wednesday (April 26). “We want to make more observations that narrow down this flow.”
According to current research, space rocks and the sun radiation The ring particles are slightly distorted and give them an electric charge that binds the gas giant’s magnetic field lines. Saturn’s gravity then pulls inward ice particles, which are directed by the magnetic field to flow into the planet’s upper atmosphere, though not always at the same speed.
As Saturn orbits the Sun in its 29.5 year orbit, it turns towards and away from the Sun, and its rings do the same. Astronomers say this tilt determines how much solar radiation affects the inner layers of the ring system – where many hail is triggered – and may also play a role in determining how much material falls on Saturn.
“We suspect that when the rings are at the edge of the sun, the ring rain will slow down,” O’Donoghue told Space.com. “And as they tilt towards the sun, the circular streams of rain will increase.”
So his team will use the Webb and Hawaiian Cake Observatories to measure the emission of certain hydrogen molecules in the upper atmosphere of Saturn. The measurements of this molecule increase when small amounts of material fall from Saturn’s icy rings into its atmosphere, but decrease when it rains heavily, O’Donoghue told Space.com. Observing this shift in hydrogen emissions over a full season on Saturn could help the team determine how much ring material should rain on the planet.
“The tool at Keck that we used for this before has been upgraded, and we haven’t used JWST for this before,” he said. “So we will be able to appreciate the flow of episodes better than before.”
While the new research will help predict the fate of the rings, astronomers studying Saturn’s world continue decades of debate about how and when the planet’s rings were born. Models have shown that the rings were permanent structures around Saturn 4.5 billion years ago – when the solar system itself formed, but data from the Cassini spacecraft paints a much younger picture, dating only 10 to 100 million. year. old.
The differences arise because older rings are often darker, but Cassini captures Saturn’s rings in a bright color, showing their youth. In 2019, astronomers who Reconsider the discussion (Opens in a new tab) He suggested that heavy circular rains might be responsible for the rings appearing at such a young age, returning to the original idea that the rings were as old as the solar system.
“I think it would be really cool if the rings were only 100 million years old or so and billions of years old,” O’Donoghue told Space.com. “Because it means we evolved in time to see them before they left.”
Follow Sharmila Kothonoor on Twitter @employee (Opens in a new tab). Follow us @employee (Opens in a new tab)or in Facebook (Opens in a new tab) And Instagram (Opens in a new tab).
2023-05-02 15:56:46
#Saturns #rings #sucked #planet
