Crash Course – Astronomy – 31: High Mass Stars

This is the thirty-first video of the Crash Course – Astronomy series, hosted by Dr. Phil Plait. This video examines the progression and ends of stars with masses greater than nine times the mass of our sun.

From the video description:

Table of Contents:

  • Massive Stars Fuse Heavier Elements Up To Iron 1:15
  • Iron Uses High Amounts of Energy, Thus Making Stars Collapse 3:58
  • The Resulting Supernova Creates Even Heavier Elements 10:00
  • Relax, Something Else Will Kill You 9:04

Crash Course – Astronomy – 30: White Dwarfs & Planetary Nebulae

This is the thirtieth video of the Crash Course – Astronomy series, hosted by Dr. Phil Plait. This video examines white dwarfs and planetary nebulae, the remains of low mass stars in old age.

From the video description:

Table of Contents:

  • When low mass stars die they form white dwarfs 0:54
  • White dwarfs are roughly the size of Earth 2:16
  • Cloudy with a chance of Planetary Nebulae 3:59
  • Life Span 9:06

Crash Course – Astronomy – 29: Low Mass Stars

This is the twenty-ninth video of the Crash Course – Astronomy series, hosted by Dr. Phil Plait. This video describes the phases of life in low-mass stars, those with masses lower than about nine times that of our sun.

From the video description:

Table of Contents:

  • Low Mass Stars Live a Long Time 0:57
  • Larger Stars (Like Our Sun) Live Shorter Lives 3:10
  • Fueled By Fusion 3:58
  • How They Turn Into Red Giants 5:45

Crash Course – Astronomy – 28: Brown Dwarfs

This is the twenty-eighth video of the Crash Course – Astronomy series, hosted by Dr. Phil Plait. This video examines brown dwarfs, objects which have a mass between the smallest stars and the largest planets.

From the video description:

Table of Contents:

  • Intermediate in Mass 1:22
  • Thousands Are Known 4:48
  • Cannot Fuse Hydrogen Like “Normal” Stars 8:46

Crash Course – Astronomy – 27: Exoplanets

This is the twenty-seventh video of the Crash Course – Astronomy series, hosted by Dr. Phil Plait. This video examines how astronomers find planets outside our solar system, and describes some of the planets found so far.

From the video description:

Table of Contents:

  • Other Planets Orbit Other Stars 2:10
  • Nearly 2000 Have Been Found 9:29
  • Transits 5:44
  • Doppler Shift 3:30
  • Exoplanets Orbit Nearly Every Kind of Star 8:44
  • Billions of Earth-Like Planets 9:33

Crash Course – Astronomy – 26: Stars

This is the twenty-sixth video of the Crash Course – Astronomy series, hosted by Dr. Phil Plait. This video describes the types of stars observed in the universe, and covers the HR diagram and the Main Sequence.

From the video description:

Table of Contents:

  • Stars Can Be Categorized Using Their Spectra 1:32
  • Spectra With Distance Can Identify Luminosity, Size, and Temperature 5:20
  • The HR Diagram Plots Luminosity vs Temperature 6:33
  • Most Stars Fall Along the Main Sequence 7:16

Crash Course – Astronomy – 25: Distances

This is the twenty-fifth video of the Crash Course – Astronomy series, hosted by Dr. Phil Plait. This video examines the different methods that astronomers use to measure distances to everything from the moon to the furthest galaxy.

From the video description:

Table of Contents:

  • Ancient Greeks Finding the Size of the Earth 1:07
  • Earth/Sun Distance Began Our Use of Parallax 5:39
  • Brightness Relation to Distance 9:07

Crash Course – Astronomy – 24: Light

This is the twenty fourth video of the Crash Course – Astronomy series, hosted by Dr. Phil Plait. This video explains how astronomers use light to observe and understand everything in the universe around us.

From the video description:

Table of Contents:

  • Light is a Form of Energy 0:39
  • Wavelength Tells Us Its Energy and Color 0:59
  • Spectroscopy 7:28

Crash Course – Astronomy – 23: Meteors

This is the twenty third video of the Crash Course – Astronomy series, hosted by Dr. Phil Plait. This video surveys the different types of meteors, and describes the differences between meteors, meteorites, and meteoroids.

From the video description:

Table of Contents:

  • What Meteors Are 0:59
  • Meteor Shower 4:22
  • What Meteors Are Made Of 7:10
  • Very Big Meteorites Can Be a Very Big Problem 8:36

Crash Course – Astronomy – 22: Oort Cloud and Outer Solar System

This is the twenty second video of the Crash Course – Astronomy series, hosted by Dr. Phil Plait. This video discusses the far away and still unobserved cloud of comets known as the Oort cloud.

From the video description:

Table of Contents:

  • Icy Bodies That Can Become Comets 0:27
  • The Kuiper Belt is a Donut Shape Aligned With the Plane of the Solar System 2:57
  • The Scattered Disk is More Eccentric and the Source of Short Period Comets 4:26
  • Oort Cloud Surrounds Our Solar System and is the Source of Long-Period Comets 4:04
  • These Bodies Probably Formed Near the Sun and Dispersed Through Gravitational Interactions 5:41