January 15, 2015 • 12m
Welcome to the first episode of Crash Course Astronomy. Your host for this intergalactic adventure is the Bad Astronomer himself, ...Read more
January 22, 2015 • 12m
Phil invites you to head outside and take a look at all the incredible things you can see with your naked eye.
January 29, 2015 • 12m
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.
February 5, 2015 • 12m
In this episode of Crash Course Astronomy, Phil takes you through the cause and name of the Moon's phases.
February 13, 2015 • 12m
The big question in the comments last week was, "BUT WHAT ABOUT ECLIPSES?" Today, Phil breaks 'em down for you.
February 19, 2015 • 12m
Today Phil explains how telescopes work and offers up some astronomical shopping advice.
February 26, 2015 • 12m
In today's episode, Phil looks at how gravity plays out across the universe.
March 5, 2015 • 12m
Today Phil explores the world of tides! What is the relationship between tides and gravity? How do planets and their moons become ...Read more
March 12, 2015 • 12m
In today's Crash Course Astronomy, Phil takes a look at the explosive history of our cosmic backyard. We explore how we went from ...Read more
March 19, 2015 • 12m
Phil takes us for a closer (eye safe!) look at the two-octillion ton star that rules our solar system. We look at the sun's core, ...Read more
April 2, 2015 • 12m
Phil starts the planet-by-planet tour of the solar system right here at home, Earth.
April 9, 2015 • 12m
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.
April 16, 2015 • 12m
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, ...Read more
April 23, 2015 • 12m
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 ...Read more
April 30, 2015 • 12m
The fourth planet from the sun and the outermost of the terrestrial planets, Mars has long been a popular spot for missions and im...Read more
May 8, 2015 • 12m
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 dy...Read more
May 14, 2015 • 12m
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 hu...Read more
May 21, 2015 • 12m
Saturn is the crown jewel of the solar system, beautiful and fascinating. It is a gas giant, and has a broad set of rings made of ...Read more
May 28, 2015 • 12m
Today we’re rounding out our planetary tour with ice giants Uranus and Neptune. Both have small rocky cores, thick mantles of ammo...Read more
June 4, 2015 • 12m
Now that we’ve finished our tour of the planets, we’re headed back to the asteroid belt. Asteroids are chunks of rock, metal, or b...Read more
June 18, 2015 • 12m
Today on Crash Course Astronomy, Phil explains comets. Comets are chunks of ice and rock that orbit the Sun. When they get near th...Read more
June 25, 2015 • 12m
Now that we’re done with the planets, asteroid belt, and comets, we’re heading to the outskirts of the solar system. Out past Nept...Read more
July 2, 2015 • 12m
Today Phil helps keep you from ticking off an astronomer in your life by making sure you know the difference between a meteor, met...Read more
July 9, 2015 • 12m
In order to understand how we study the universe, we need to talk a little bit about light. Light is a form of energy. Its wavelen...Read more
July 16, 2015 • 12m
How do astronomers make sense out of the vastness of space? How do they study things so far away? Today Phil talks about distances...Read more
July 23, 2015 • 12m
Today Phil’s explaining the stars and how they can be categorized using their spectra. Together with their distance, this provides...Read more
July 30, 2015 • 12m
Today Phil explains that YES, there are other planets out there and astonomers have a lot of methods for detecting them. Nearly 20...Read more
August 13, 2015 • 12m
While Jupiter is nowhere near massive enough to initiate fusion in its core, there are even more massive objects out there that fa...Read more
August 20, 2015 • 12m
Today we are talking about the life -- and death -- of stars. Low mass stars live a long time, fusing all their hydrogen into heli...Read more
August 27, 2015 • 12m
Today Phil follows up last week’s look at the death of low mass stars with what comes next: a white dwarf. White dwarfs are incred...Read more
September 10, 2015 • 12m
Massive stars fuse heavier elements in their cores than lower mass stars. This leads to the creation of heavier elements up to iro...Read more
September 17, 2015 • 12m
In the aftermath of a 8 – 20 solar mass star’s demise we find a weird little object known as a neutron star. Neutrons stars are in...Read more
September 25, 2015 • 12m
We’ve covered a lot of incredible stuff, but this week we’re talking about the weirdest objects in space: BLACK HOLES. Stellar mas...Read more
October 1, 2015 • 12m
Double stars are stars that appear to be near each other in the sky, but if they’re gravitationally bound together we call them bi...Read more
October 8, 2015 • 12m
Last week we covered multiple star systems, but what if we added thousands or even millions of stars to the mix? A star cluster. T...Read more
October 15, 2015 • 12m
Astronomers study a lot of gorgeous things, but nebulae might be the most breathtakingly beautiful of them all. Nebulae are clouds...Read more
October 22, 2015 • 12m
Today we’re talking about our galactic neighborhood: The Milky Way. It’s a disk galaxy, a collection of dust, gas, and hundreds of...Read more
October 29, 2015 • 12m
The Milky Way is our neighborhood in the universe. It’s a galaxy and there are many others out there. Galaxies contain gas, dust, ...Read more
November 5, 2015 • 12m
Active galaxies pour out lots of energy, due to their central supermassive black holes gobbling down matter. Galaxies tend not to ...Read more
November 12, 2015 • 12m
Gamma-ray bursts are not only incredible to study, but their discovery has an epic story all its own. Today Phil takes you through...Read more
November 19, 2015 • 12m
Today on Crash Course Astronomy, Phil dives into some very dark matters. The stuff we can actually observe in the universe isn’t a...Read more
November 26, 2015
Thanks to observations of galaxy redshifts, we can tell that the universe is EXPANDING! Knowing that the universe is expanding and...Read more
December 3, 2015
The majority of the universe is made up of a currently mysterious entity that pervades space: dark energy. We don’t know exactly w...Read more
December 10, 2015
Thanks to the wonders of physics, astronomers can map a timeline of the universe’s history. Today, Phil’s going to give you an ove...Read more
December 17, 2015
As we approach the end of Crash Course Astronomy, it’s time now to acknowledge that our Universe’s days are numbered. Stars will d...Read more
December 24, 2015
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 o...Read more