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 ...
One last round of laughs with Phil as he struggles through some Bad Astronomy. -- Crash Course Astronomy Poster: ...
Today we're rounding out our planetary tour with ice giants Uranus and Neptune. Both have small rocky cores, thick mantles of ammonia, water, and methane, ...
How do astronomers make sense out of the vastness of space? How do they study things so far away? Today Phil talks about distances, going back to early ...
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 ...
Astronomers study a lot of gorgeous things, but nebulae might be the most breathtakingly beautiful of them all. Nebulae are clouds of gas and dust in space.
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 wavelength tells us its energy and color.
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 ...
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 ...
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, plasma, magnetic fields, sunspots, ...
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 ...
Active galaxies pour out lots of energy, due to their central supermassive black holes gobbling down matter. Galaxies tend not to be loners, but instead exist in ...
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.
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 ...
Today we're taking a break for another round of "Bad Astronomy" Crash Course Astronomy posters available at DFTBA.com ...
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 ...
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 ...
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 both that were once part of ...
Today we're going to do something a little bit different and take everything we've learned so far and apply it to a case study on (arguably) the biggest game ...
As we approach the end of Crash Course Astronomy, it's time now to acknowledge that our Universe's days are numbered. Stars will die out after a few trillion ...
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 ...
Content warning: today's episode contains language that some viewers might find upsetting and that may not be viewable in all settings. We've talking about ...
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 incredibly dense, spin rapidly, and ...
Sometimes even Phil has a hard time with Astronomy. Time for another Bad Astronomy break! Crash Course Astronomy posters available at DFTBA.com ...
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.
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 ...
Today we are talking about the life -- and death -- of stars. Low mass stars live a long time, fusing all their hydrogen into helium over a trillion years.
Last week we covered multiple star systems, but what if we added thousands or even millions of stars to the mix? A star cluster. There are different kinds of ...
Today Phil's explaining the stars and how they can be categorized using their spectra. Together with their distance, this provides a wealth of information about ...