In this episode of Crash Course Astronomy, Phil takes you through the cause and name of the Moon's phases. -- Why the Moon Has Phases 0:36.1 Spheres in ...
The big question in the comments last week was, "BUT WHAT ABOUT ECLIPSES?" Today, Phil breaks 'em down for you. This episode is sponsored by ...
Today Phil explains how telescopes work and offers up some astronomical shopping advice. -- How Telescopes Work 1:07 Refractors vs Reflectors 2:50 ...
Sometimes even Phil has a hard time with Astronomy. Time for another Bad Astronomy break! Crash Course Astronomy posters available at DFTBA.com ...
Today Phil explores the world of tides! What is the relationship between tides and gravity? How do planets and their moons become tidally locked? What would ...
Here it is, folks: the end. In our final episode of Crash Course Astronomy, Phil gives the course a send off with a look at some of his favorite topics and the big ...
The Milky Way is our neighborhood in the universe. It's a galaxy and there are many others out there. Galaxies contain gas, dust, and billions of stars or more.
We've covered a lot of incredible stuff, but this week we're talking about the weirdest objects in space: BLACK HOLES. Stellar mass black holes form when a ...
Before moving on from Jupiter to Saturn, we're going to linger for a moment on Jupiter's moons. There are 67 known moons, and 4 huge ones that we want to ...
Welcome to the first episode of Crash Course Astronomy. Your host for this intergalactic adventure is the Bad Astronomer himself, Phil Plait. We begin with ...
Gamma-ray bursts are not only incredible to study, but their discovery has an epic story all its own. Today Phil takes you through some Cold War history and then ...
The majority of the universe is made up of a currently mysterious entity that pervades space: dark energy. We don't know exactly what it is, but we do know that ...
Thanks to the wonders of physics, astronomers can map a timeline of the universe's history. Today, Phil's going to give you an overview of those first few minutes ...
Venus is a gorgeous naked-eye planet, hanging like a diamond in the twilight -- but it's beauty is best looked at from afar. Even though Mercury is closer to the ...
Today we're talking about our galactic neighborhood: The Milky Way. It's a disk galaxy, a collection of dust, gas, and hundreds of billions of stars, with the Sun ...
Today on Crash Course Astronomy, Phil dives into some very dark matters. The stuff we can actually observe in the universe isn't all there is. Galaxies and other ...
Now that we're done with the planets, asteroid belt, and comets, we're heading to the outskirts of the solar system. Out past Neptune are vast reservoirs of icy ...
Today Phil helps keep you from ticking off an astronomer in your life by making sure you know the difference between a meteor, meteorite, and meteoroid.
Massive stars fuse heavier elements in their cores than lower mass stars. This leads to the creation of heavier elements up to iron. Iron robs critical energy from ...
Jupiter is the biggest planet in our solar system. The gas giant is NOT a failed star, but a really successful planet! It has a dynamic atmosphere with belts and ...
While Jupiter is nowhere near massive enough to initiate fusion in its core, there are even more massive objects out there that fall just short of that achievement ...
Join Phil for a tour of our capital-M Moon, from surface features, inside to the core, and back in time to theories about its formation. This episode is brought to you ...
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. -- Table of ...
Updated with graphics fixed. Thanks for pointing that out! Ever wonder why we have seasons? A lot of people think it's because the Earth gets further away from ...
The fourth planet from the sun and the outermost of the terrestrial planets, Mars has long been a popular spot for missions and imagination. Phil walks you ...
In today's Crash Course Astronomy, Phil takes a look at the explosive history of our cosmic backyard. We explore how we went from a giant ball of gas to the ...
Mercury is the closest planet to the sun. It has no atmosphere and is, as such, covered in craters. It's also incredibly hot but, surprisingly, has water ice hiding ...