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This weekend, Saturn's iconic rings will seemingly vanish from view due to a rare celestial event known as a "ring plane crossing." During this phenomenon, which occurs every 13 to 15 years, Saturn's rings align edge-on with Earth, making them appear nearly invisible. The last time this happened was in 2009.
The event will begin on Sunday (March 23) at 12:04 p.m. EDT (1604 GMT) and will last for a few days. During this time, Saturn's rings will look like a thin line across the planet's disk. This illusion is caused by the specific tilts of both Earth and Saturn as they orbit the sun. Saturn's rings are made up of billions of ice and rock particles, and when aligned edge-on, they reflect very little light, making them difficult to see.
Unfortunately, most skywatchers will not be able to witness this event as Saturn will be too close to the sun and low on the eastern horizon during morning twilight. However, the next full-ring plane crossing visible from Earth will occur in 2038.
Despite the rings' temporary disappearance, this event provides a unique opportunity to observe Saturn's moons. The lack of reflected light from the rings allows smaller moons to become visible.
For those interested in viewing Saturn, the best opportunity this year will be during its opposition on September 21, 2025, when the planet will be at its brightest in Earth's sky.