Active galaxies pour out lots of energy. 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 ...

Phil gives the course a send off with a look at some of his favorite topics. 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 ...

For this week’s Crash Course Astronomy episode, we take a skidding halt at the edge of the planetary solar system and scream back inward to the vast space between Mars and Jupiter. Before I go on, I ...

In 2011, brothers John and Hank Green created an educational YouTube channel called “Crash Course” with the goal of spreading high-quality educational videos for everyone, free of charge. A year later ...

Forty-eight episodes, more than eight hours of content, 100,000 words, a year and a half of work, topics ranging from quantum fluctuations to the death of the Universe, and 12 million views … finally, ...