Stars: Crash Course Astronomy #26

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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 them including their luminosity, size, and temperature. The HR diagram plots stars’ luminosity versus temperature, and most stars fall along the main sequence, where they live most of their lives.

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

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Stars [credit: ESA/Hubble & NASA]
Spitzer Spectrum [credit: NASA/JPL-Caltech/Leiden/SRON]
Sun spectrum [credit: N.A.Sharp, NOAO/NSO/Kitt Peak FTS/AURA/NSF]
Annie Jump Cannon [credit: New York World-Telegram and the Sun Newspaper]
Cecilia Payne-Gaposchkin [credit: Smithsonian Institution]
Betelgeuse [credit: ESO/Digitized Sky Survey 2. Acknowledgment: Davide De Martin]
Sirius [credit: NASA, ESA, H. Bond (STScI) and M. Barstow (University of Leicester)]
Solar AM0 spectrum with visible spectrum background [credit: Danmichaelo, Wikimedia Commons]
Blue sky [credit: Skitter Photo]
Hawaii sunset photo [credit: Phil Plait]
Hertzsprung-Russell Diagram [credit: ESO]


Michael Nebiker says:


Anthony Pedraza says:

typically i lay in bed close my eyes and throw on one of these shows.

first thing i hear
twinkle twinkle little star

creepy voice
oooh i know who you are

me 😅

William Schubert says:

can I have that Lego Darth Vader please

hanieh Najafy Moghadam says:

1:05 😂😂😂😂

Matthew Waterman says:

nice legos old man lol i really love ur vids please keep making some

Tessa Haywood says:

i love the stars

Young_BlackOpp says:

When he said for science Lmao

Zadfrack says:

Why Planck fig. 26.2?

Lewis K says:

19 years old and I've finally learned the age old question, "Why is the sky blue?" this is amazing

Rim Shayakhmetov says:

Why do stars have a cross shape through them in the images?

insertname here says:

I love this series!!!!!!!!

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