Optics

Cosmological redshift: sounds like the latest blockbuster coming to a theater near you, doesn't it? In reality, it has to do with how light itself travels -- and understanding how it works is essential to advanced space telescope technology.

By Kate Kershner

It's a young lady! It's an old woman! It's a blue dress! No, it's gold! Why are we fooled by optical illusions and what do they tell us about how the brain works?

By Meisa Salaita

Kaleidoscopes have been fascinating people since the early 19th century. Whether you think of kaleidoscopes as toys or as works of art, no matter how often you look inside, you'll never see the same thing twice.

By Melanie F. F. Gibbs

Seven ounces a ray! No, that's a lie. Measuring the weight of light is not as straightforward as that. So what's the more complicated explanation?

By Kate Kershner & Yara Simón

If you're one of those people who chooses invisibility as your desired superpower, it could mean you have a dark side.

By Alia Hoyt

Why do we love looking at a perfectly stacked display of soup cans or six flower petals around a stamen? Our brains seem wired for it -- but why?

By Dave Roos

Primary colors are the blocks from which all other colors are built. But there's a lot more to know about them than the basic red, yellow and blue we learned about in kindergarten.

By Michelle Konstantinovsky & Desiree Bowie

Modern color theory got its start with, believe it or not, Sir Isaac Newton, who also discovered a little thing called gravity and invented calculus.

By Jesslyn Shields