The 2026 Nobel Prize in chemistry concerns a property called chirality, which may sound like an abstract science term but is actually all around you, all the time.

Picture a spiral galaxy rotating in space, or follow the outline of a snail’s shell as it spirals clockwise to the tip. In each case, you can draw a mirror image of the spiral that won’t overlap with the original picture.

You can even see this property on your own body: Hold out your hands, palms up. Your hands are mirror images of one another, yet however you turn them, you can never lay your right hand exactly on top of your left with both palms facing the same way.

All of these are examples of chirality. Chiral objects have a mirror image that cannot be superimposed directly on them. This concept shows up in geometry in the shapes of organisms and, most consequentially, in the molecules that make up living things. This week, the 2026 Nobel Prize in chemistry went to Henri Kagan and Kenso Soai for their work on how chemistry can favor one chiral version, or “hand,” over the other.

Why handedness matters

As chemists who design and measure chiral molecules, we work with this mirror-image problem every day. Molecular handedness has far-reaching implications, and you can see why when you consider how chiral objects interact with one another in daily life.

A regular claw hammer is an achiral, or nonchiral, tool. It works identically whether you hold it in your left hand or right hand. But a pair of scissors is often made to favor a right-handed user. If you are left-handed and have used right-handed scissors, you know the result: Squeezing them with your right hand pulls the blades inward against each other, while squeezing them with the left pushes the blades outward, so they fold the paper instead of cutting it. Scissors are chiral tools designed to interact with the human hand, which is also chiral.

Nearly every protein on Earth is built from one mirror-image form of each amino acid, and DNA and RNA from one form of sugars. DNA assembles to form helices of one, and only one, chirality.........

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