One of the most fundamental physics facts is that the speed of light in a vacuum is constant for all observers. But can we really be sure that the speed of light wasn’t different in the past, or perhaps in other parts of the universe? In...

Over 200 years ago, scientists were looking at sunlight through a prism when they noticed that part of the rainbow was missing. There were dark lines where there should have been colors. Since then, scientists have unlocked the secrets...

Solar eclipses don't just happen here on earth - moons of other planets also pass between those planets and the sun, resulting in various types of solar eclipses on Mars, Jupiter, Saturn, Uranus, Neptune, and even non-planets like Pluto,...

For centuries, humans have reported animals freaking out during solar eclipses, like birds falling from the sky and bees hiding in their hives, but the animals most affected by eclipses might be us.

Have you ever wondered why you look up and see a dark sky at night?

Thanks to the Space Telescope Science Institute (STScI) and NASA's James Webb Space Telescope for supporting this video! In particular, thanks to Dan Coe of STScI for taking the time to chat with me about what we do and don't know about...

What was the 2012 Nobel Prize in physics given for? Capturing a single photon of light!

There are more than 2,000 firefly species, found on every continent except for Antarctica — an astonishing diversity of movement and light. Firefly scientist Wan Faridah Akmal Jusoh explores the mysteries of these little beetles that...

You might have heard of the ongoing volcanic eruptions near Grindavík, Iceland. You might not have heard that it's hard to monitor a volcano in the dark. We'll talk about why an Icelandic winter is the worst time for monitoring equipment...

Dark matter's most famous trait is its inability to interact with light, the particle version of which we call "photons". But in their attempts to figure out exactly what dark matter is, some scientists have proposed "dark photons".

More than a classic rock album that'll change your life, this classic space rock has a dark side that has mystified scientists for centuries.

2022 was a pretty exciting year for space science, but what news might we expect in the coming year?

It may be that for every star in the universe there are billions of microscopic black holes streaming through the solar system, the planet, even our bodies every second. Sounds horrible - but hey, at least we’d have explained dark matter.

It never gets dark anymore. Not REALLY dark, anyway. Not like it used to. Light pollution is not only making it more difficult to see the night sky, but it's also affecting our health. For the past century and a half, since the dawn of...

Most of us can only see certain wavelengths of light our entire lives. So why can salmon switch on night vision? We'll learn how they can reshape their eyes to see into the infrared.

One Minute Physics provides an energetic and entertaining view of old and new problems in physics -- all in one minute!

Most animals on earth are bioluminescent, but almost all of them live in the ocean - and scientists aren’t sure why.

Visual Illusions: Why You See Things That Aren't There

Plants are finding their ways into caves, and it's all our fault.

Thanks to the Monterey Bay Aquarium and their research and technology partner MBARI for partnering with us on this episode of SciShow. They worked together on an exhibition, “Into The Deep: Exploring Our Undiscovered Ocean,” to give...

If you're lucky enough to find a glowing rock, it likely doesn't mean you're the chosen one. In fact, it could have to do with one of these five phenomena! Learn about the quantum mechanics of glowing rocks in this new SciShow Episode...

Why do exams always tell you to use a number 2 pencil? What happens if you don’t? Quick Questions explains!

Some days you look in the mirror and find a long dark hair where it didn't use to be. Maybe you're going through puberty, pregnancy, or menopause. Maybe you're not. But either way, that hair didn't appear out of nowhere. It just went...

The chemistry behind film photography is pretty fascinating. How do film cameras help us turn light into a physical image?