When you view short bursts of moving images, you see some interesting effects.

A series of slits moving rapidly past your eye allows you to see images in short bursts. Such rapid but fragmented views of moving objects can make the objects appear to jerk along, change speed, or even move backward.

Copy of the stroboscope [...]

A face seen upside down may hold some surprises.

Your brain gets used to seeing familiar things in certain ways. When the brain receives a strange view of a familiar object, the consequences can be intriguing. In the Exploratorium exhibit titled “Vanna,” two pictures of the face of TV personality Vanna White seem identical when [...]

This visual illusion makes the palm of your hand appear to squirm and twist.

If you stare at a waterfall for some time, and then stare at the rocks nearby, the rocks will appear to be moving upward. This illusion is known as the waterfall effect. Using the pattern provided here, you can create the [...]

Why is the sky blue? That’s a sticky question.

The scattering of light by the atmosphere, which creates the blue sky and red sunsets, can be modeled when light from a flashlight shines through clear glue sticks.

Mini-MagLite or penlight (a regular flashlight can also be used, but its larger [...]

Stare at color and see it change.

You see color when receptor cells (called cones) on your eye’s retina are stimulated by light. There are three types of cones, each sensitive to a particular color range. If one or more of the three types of cones becomes fatigued to the point where it responds less [...]