Season
Season 1 Episode
- Season 1 Introduction to Astronomy
- Season 1 Naked Eye Observations
- Season 1 Cycles in the Sky
- Season 1 Moon Phases
- Season 1 Eclipses
- Season 1 Telescopes
- Season 1 The Gravity of the Situation
- Season 1 Tides
- Season 1 Introduction to the Solar System
- Season 1 The Sun
- Season 1 The Earth
- Season 1 The Moon
- Season 1 Mercury
- Season 1 Venus
- Season 1 Mars
- Season 1 Jupiter
- Season 1 Jupiter's Moons
- Season 1 Saturn
- Season 1 Uranus & Neptune
- Season 1 Asteroids
- Season 1 Comets
- Season 1 The Oort Cloud
- Season 1 Meteors
- Season 1 Light
- Season 1 Distances
- Season 1 Stars
- Season 1 Exoplanets
- Season 1 Brown Dwarfs
- Season 1 Low Mass Stars
- Season 1 White Dwarfs & Planetary Nebulae
- Season 1 High Mass Stars
- Season 1 Neutron Stars
- Season 1 Black Holes
- Season 1 Binary and Multiple Stars
- Season 1 Star Clusters
- Season 1 Nebulae
- Season 1 The Milky Way
- Season 1 Galaxies, Part 1
- Season 1 Galaxies, Part 2
- Season 1 Gamma-Ray Bursts
- Season 1 Dark Matter
- Season 1 The Big Bang, Cosmology Part 1
- Season 1 Dark Energy, Cosmology Part 2
- Season 1 A Brief History of the Universe
- Season 1 Deep Time
- Season 1 Everything, The Universe...And Life
Crash Course Astronomy - Season 1 Episode 35 Star Clusters
8.00 12 minutes 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 clusters, though. Open clusters contain hundreds or thousands of stars held together by gravity. They’re young, and evaporate over time, their stars let loose to roam space freely. Globular clusters, on the other hand, are larger, have hundreds of thousands of stars, and are more spherical. They’re very old, a significant fraction of the age of the Universe itself, and that means their stars have less heavy elements in them, are redder, and probably don’t have planets (though we’re not really sure).
