Why does Saturn disappear behind the Moon?

Short answer: Saturn does not actually disappear. The Moon passes in front of it, an event astronomers call an occultation. NASA's Astronomy Picture of the Day for November 10, 2026 shows one, seen in early 2025 and photographed from Sardinia, Italy.

The primary source for this article is NASA's Astronomy Picture of the Day, Saturn Behind the Moon (November 10, 2026), image credit Roberto Ortu.

What is an occultation?

An occultation is when one astronomical object passes in front of another and either completely or partially blocks it. That is the definition NASA gives in its October 28, 2026 picture, The Mutual Occultation of Ganymede and Io.

In this case the Moon is the object in front and Saturn is the one blocked, which is why Saturn seems to disappear. NASA's November 10 caption says the event is "more formally called an occultation."

Where could people see this one?

Only from part of the planet. According to NASA, this occultation "was visible in early 2025 along a small swath" of Earth, running "from Greenland through central Europe and into northern Africa."

How was the picture made?

The featured image is not a single exposure. NASA describes it as "a digital fusion of three images": one of Saturn just before it disappeared, and two of the Moon with different exposure lengths. The photographer took them from Sardinia, Italy, after sunset.

What is the bright dot next to Saturn?

It is easy to mistake it for one of Saturn's moons. It is not. NASA identifies it as the star 85 Aquarii, "which is further behind Saturn than Saturn is behind the Moon." So the picture lines up three objects at very different distances: the Moon in front, Saturn behind it, and a background star far beyond both.

When will the Moon cover Saturn again?

Not soon. According to NASA's caption, the next time the Moon moves in front of Saturn, as visible from some place on Earth, "will be in 2031."

What do we know, and what is still open?

What is confirmed, from NASA's caption: the event was an occultation, visible in early 2025 along a path from Greenland through central Europe into northern Africa; the picture combines three images taken from Sardinia, Italy, after sunset; the bright point nearby is the star 85 Aquarii; and the next occultation of Saturn by the Moon visible from Earth is in 2031.

What this article does not cover: the exact date and time of the 2025 event, and the date and viewing region of the 2031 occultation. NASA's caption gives the year only, so check a current sky calendar closer to the time if you hope to see it.

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