Tag Archives: Bad Astronomer

Saturn: Crash Course Astronomy #18

This episode of Crash Course is brought to you by Squarespace. So now we’ve come to the last of the naked eye planets in the solar system: Saturn. It’s the second largest planet, but ironically the least dense. In fact, if you could find a bathtub big enough, Saturn would float in it! But it… Read More »

Uranus & Neptune: Crash Course Astronomy #19

This episode of Crash Course is brought to you by Squarespace. You run us. YOU run us. You RAN us. You ran us. Ooo- Ooo ran ose. There are five planets in our solar system you can see without a telescope; well, six if you include the one you’re sitting on. But there are two… Read More »

The Gravity of the Situation: Crash Course Astronomy #7

We live — and stop me if I’m going too fast — on a planet. I mean, sure, duh. But this isn’t the natural state of the Universe; or, at least, it’s not the way things usually are. Most of the Universe is pretty empty — that’s why we call it “space” — and if… Read More »

Introduction to the Solar System: Crash Course Astronomy #9

The Solar System is the name we give to our local cosmic backyard. A better way to think of it is all the stuff held sway by the Sun’s gravity: The Sun itself, planets, moons, asteroids, comets, dust, and very thin gas. If you took a step back — well, a few trillion steps back… Read More »

Venus: Crash Course Astronomy #14

This episode of Crash Course is brought to you by SquareSpace Venus was the Roman goddess of love, and honestly, if you’ve ever seen it after sunset, hanging like a diamond in the twilight, the planet Venus is stunningly beautiful. The only problem? Venus is hell. Venus is the second rock from the Sun, closer… Read More »

Mercury: Crash Course Astronomy #13

Mercury is the closest planet to the Sun. As you might expect, that makes it pretty hot. But also, it’s pretty cool. There are seven naked-eye solar system objects in the sky: Mercury, Venus, Mars, Jupiter, Saturn, the Sun, and the Moon. Seven. Each of them was associated with a god in ancient times. Mercury… Read More »

Mars: Crash Course Astronomy #15

Hey folks, I’m Phil Plait and this is Crash Course Astronomy. You know, I can’t think of any object in the sky that’s captured our imagination like Mars has. The Red Planet was once thought to be the god of war, and in more modern times has been the setting for a zillion science fiction… Read More »

The Earth: Crash Course Astronomy #11

The Earth is a planet. That’s a profound statement, and one that’s not really all that obvious. For thousands of years, planets were just bright lights in the sky, one-dimensional points that wandered among the fixed stars. How could the Earth be one of them? With the invention of the telescope those dots became worlds,… Read More »

Distances: Crash Course Astronomy #25

Oh. Hey! Sorry, I don’t mean to be rude. I’m just trying to figure out how far away my thumb is. How? Parallax. Centuries ago, people thought the stars were holes in a huge crystal sphere, letting through heavenly light. It wasn’t clear just how big the sphere was, but it was pretty dang big.… Read More »