Do You See Craters or Bumps on the Moon’s Surface?
When you look up at the full moon on a clear night, you might notice strange patterns on its surface — round shapes, shadows, and textures that resemble either craters or raised bumps. But which is it? Are we seeing depressions carved into the moon’s face, or hills and mountains reaching out into space?
The answer is both fascinating and a little tricky — and it depends on how light and shadow play across the lunar surface.
A Surface Full of Craters
The moon’s surface is covered in craters, the result of billions of years of meteorite impacts. With no atmosphere to burn up incoming objects, even small meteors have left their mark. Some craters are vast, like the South Pole–Aitken Basin, one of the largest in the solar system, while others are only a few meters wide.
These craters create a pitted, rugged texture. But sometimes, depending on the angle of sunlight, they may appear as bumps instead of holes.
The Optical Illusion of Light and Shadow
Our brains rely on shadows to understand depth and shape — but we’re used to seeing light come from above, like the sun shining down during the day. When we see the moon from Earth, the light from the sun often hits it from the side, especially during the crescent or gibbous phases. This can confuse our perception.
For example, a crater lit from below (as we see it from our position) may appear like a bump or dome. This optical illusion is well-known among astronomers and photographers. In fact, if you flip an image of the moon upside down, the craters may suddenly look like raised hills — even though you haven’t changed the actual topography.
Mountains, Too
The moon does have mountains, especially around the edges of large impact basins. These were formed by the force of collisions or tectonic activity in the moon's early history. Some of the most famous are the Montes Apenninus and Montes Alpes ranges, which are visible with good binoculars or a telescope.
What Are You Really Seeing?
So, do you see craters or bumps? The moon’s surface is physically full of craters, but thanks to tricks of light and shadow, your eyes may sometimes turn them into bumps. It’s one of many ways that space continues to surprise and challenge our perceptions.
Next time you gaze up at the moon, take a closer look. And if you're still unsure whether you're seeing holes or hills — try turning the photo upside down. You might be amazed at how quickly your mind changes what it sees.
