This week we build on our naked eye observations from last week and take a look at the cyclical phenomena that we can see at work in the universe.

Today on Crash Course Astronomy, Phil invites you to head outside and take a look at all the incredible things you can see with your naked eye.

A backyard astronomer holds the world record for most supernovas found by searching manually. He's memorized what over a thousand galaxies look like.

Today Phil explains that YES, there are other planets out there and astonomers have a lot of methods for detecting them. Nearly 2000 have been found so far. The most successful method is using transits, where a planet physically passes...

It's School of YouTube Week! Comic Relief and YouTube are partnering to send students to school! The Bad Astronomer Phil Plait teaches Hank how to measure the distance to the stars.

For most of human history, we didn't know that galaxies were a thing. So over the past century, astronomers have been working to understand how galaxies come to be and how they evolve over time. And for a full decade, there was one...

TESS found 3 new exoplanets around a strangely calm m-dwarf star, and it's possible they could be habitable!

How can the tiny moon eclipse the sight of the gargantuan sun? By sheer coincidence, the disc of the sun is 400x larger than the disc of the moon, but the sun is 390x farther from Earth -- which means that when they align just right, the...

The results are in from the neutron star collision this past August! Astronomers are revealing what they've learned so far, with more pure gold research underway!

How many stars are there in the universe? This question leads Hank to a couple other questions - How many stars can we see from Earth? How many stars are there in our galaxy? - but the answer to the original question proves elusive.

HAS SPACE ALWAYS BEEN BLACK? As long as we've been around, YES. But the universe gets much more exciting, AND much BRIGHTER, as we start winding our clocks back to the early days of the universe. Near the beginning of the universe, when...

Learn about hypergiant stars -- stars that make the sun look ridiculously tiny.

Przybylski’s Star has been puzzling astronomers for decades, and it might contain elements or isotopes that scientists have never seen before!

For years, astronomers have been unable to find up to half of the baryonic matter in the universe. We may just have solved this problem.

So you know what a star is, right? Well, if you don't, you should. We've talked about that big one in the sky a few times: The Sun! But there are a lot of bright dots in the night sky and not all of them are stars. Today, let's play a...

Exoplanets have taught us a lot more about planets than our solar system could ever teach us, from what happens when they’re born, to what happens when their stars die.

So, have you ever wondered why some stars are brighter than others? You might think it's because they're closer to us, but that's not the whole story? In this episode of Crash Course Kids, Sabrina chats about how stars glow and how...

Some astronauts have reported the same specific symptoms: they see mysterious flashes of light out of the corner of their eyes. What causes those bizarre phenomena, and how does it affect astronauts?

There is a question that has been tossed around by philosophers and art critics for decades: how much should an artist's intention affect your interpretation of the work? Do the artist’s plans and motivations affect its meaning? Or is...

Black Holes are known for consuming everything that falls into them, but is there a point where these galactic devourers can't stomach anymore?

The Andromeda galaxy is heading straight toward our own Milky Way. The two galaxies will inevitably collide. Will that be the very last night sky our solar system witnesses?

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

Artificial Intelligence has helped astronomers discover 2 new planets in systems that we'd already looked at, and new theories about how Mars lost some of its water have surfaced.

With exoplanets, often we want to know if they are Earth-like and whether they might host life, but we can also learn a lot from planets that are nothing like Earth.