
Starting this weekend, Saturn's iconic rings will "disappear" for a few days from the vantage point of Earth for the first time since 2009. The rings would not vanish but will just seem invisible from our point of view due to a cosmic illusion between the Earth and Saturn. This scenario occurs every 13 to 15 years. Saturn's rings aligning in a perfect manner with our line of sights. This phenomenon is called "ring plane crossing".
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This will start on Sunday (March 23) at around 16:04 GMT.
Since Saturn's axis is tilted 26.73 degrees from vertical because it orbits the sun and Earth has 23.5-degree tilt and this also rotates around the sun - the illusion takes place.
“They literally almost disappear,” said Sean Walker, an associate editor at Sky & Telescope, a monthly magazine about science and amateur astronomy.
“Normally you see the rings around Saturn, but when you have an edge-on view, it looks like a hair-thin line of light just cutting across," he added.
Saturn's rings were seen gradually thinning when it was viewed from ground-based telescope in recent months. This is a temporary illusion as the rings will soon start being visible in a day or two. But, the phenomenon is still rare.
It takes 29.4 years to Saturn to make one orbit around the sun and the event occurs twice during these years.
As much as the event is exciting and unique, skywatchers would not be able to see it as the Saturn will be too close to the sun.
Walker at Sky & Telescope claimed he witnessed a ring plane crossing in 1995, using a backyard telescope.
“It was fantastic! It looked like a different planet. I spent a good part of the night just drinking in that view," he added.
The next time this will happen? 2038.
(With inputs from agencies)