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In 2025, Saturn’s spectacular rings will disappear. But it won’t be too long before they come back into sight in all their splendor. Their disappearance, after all, is all a matter of perspective.
A combination of thin rings, Saturn’s tilt, and Earth’s own orbital movements will make the rings disappear from our perspective. Saturn’s rings will be nearly edge on for the whole year, but we will see them totally edge on in March and November, says Jonti Horner, astrobiologist and astronomer at the University of Southern Queensland.
That means viewing the rings through anything other than a very powerful telescope will be close to impossible. The last time this happened was in 2009 and it will continue to occur for years to come.
“If you want to see the rings, now’s your chance, because they’re going away for a couple of years,” says Horner. “But they will be back.”
There are several complex factors that make the temporary disappearance of the rings possible. First is the relatively thin width of the rings that wrap around Saturn’s equator, says Horner.
Despite being a whopping 282,000 kilometers across, the rings measure only a few meters in thickness at certain points.
“They stretch out multiple times the planet’s radius, and they’re really thin, so that if you were ever looking at them perfectly edge on, you’re just not going to see them unless you’ve got an incredibly powerful telescope,” he says.
Another factor is that Saturn has seasons as it orbits the sun, just like we do on Earth. Unlike Earth, however, Saturn takes approximately 29.4 years to orbit the sun.
“If you’re looking at Saturn while it’s got its seasons, it would appear to nod towards you, back and forwards as it goes round the sun, because it’s tilted,” says Horner, this tilt is crucial because it means our perspective from Earth shifts.
“From our point of view, we see Saturn nodding backwards and forwards, which means twice in every Saturn orbit, we get the rings pretty much edge on,” says Horner.
When referencing Saturn “edge on,” Horner says it is like holding a thin piece of paper horizontally in front of you. Doing so makes the paper almost disappear. Because of Earth’s own wobbling orbit, the rings are hardly visible twice in one year.
Read More: How Did Saturn Get Its Rings?
But one day, Saturn will lose its rings for good. That’s because due to its immense size, the planet’s gravitational pull is dragging the icy particles and fragments that form the rings down. NASA scientists have estimated that the full disappearance of the rings won’t occur for at least 100 million years.
“Most people seem to accept that on time scales of 10’s of 100’s of millions of years, Saturn’s rings will gradually get less and less impressive, and then go away, unless they’re replenished from somewhere,” says Horner.
Saturn’s rings are thus viewed as a “transient phenomenon.” It’s possible that Mars, for example, once had its own impressive ring belt and it may have it again in around 70 million years as its moon, Phobos, tumbles inwards on its orbit and disintegrates. Fragments could form rings.
So, questions remain about Saturn’s rings, says Horner. “The rings have been known in one form or another for about 400 years,” he says. “You’d think we had a good handle on what they are, but there are still people doing research into how long lived they are and what their origin was.”
But what is certain is that when they slide out of view in 2025, Saturn’s rings will return. By 2032, the rings will face Earth again offering stargazers a perfect opportunity to see them. They likely won’t be disappearing completely for millions of years.
Read More: Mysterious, Saturn-Like Stars Steal Their Rings From Nearby Stars
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Sean Mowbray is a freelance writer based in Scotland. He covers the environment, archaeology, and general science topics. His work has also appeared in outlets such as Mongabay, New Scientist, Hakai Magazine, Ancient History Magazine, and others.