Why Does the Moon Look Bigger Near the Horizon?

• Bilkul Online | Sunday Special

Have you ever looked up at the sky and thought, “Wow! The Moon looks much bigger tonight!” You are not imagining it—but there is a twist.

The Moon does sometimes appear larger, especially when it is close to the horizon. But most of the time, the Moon itself hasn’t suddenly grown bigger. What changes is how our brain sees it.

The Moon Illusion

When the Moon is near the horizon, we see it alongside familiar objects such as buildings, trees and distant hills. Our brain uses these objects as a kind of size reference, making the Moon appear much larger than it really is.

When the same Moon climbs high into the sky, there are fewer objects around it for comparison. It can then appear smaller.

This is called the Moon illusion.

But what about a Supermoon?

There is also a real reason the Moon can look slightly bigger.

The Moon’s orbit around Earth is not a perfect circle. It is slightly oval-shaped. This means the Moon is sometimes closer to Earth and sometimes farther away.

When a full Moon occurs near its closest point to Earth, it is called a supermoon. It really is somewhat larger and brighter than an average full Moon.

But here’s the fun part: the dramatic “giant Moon” effect we see near the horizon is largely an illusion—not the Moon suddenly becoming enormous.

So, is the Moon playing tricks on us?

Not exactly. Our eyes see the Moon, but our brain decides how big it looks.

Next time you see a huge orange Moon rising over the horizon, take a photograph of it and compare it with a photo taken later when the Moon is high in the sky. You may be surprised by how similar its size actually is.

WHY IS IT SO?

Because sometimes, the Moon isn’t getting bigger.

Our perception is.

Know something that makes you say “Why is it so?” Send it our way.