Galaxies, part 1: Crash Course Astronomy #38

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The Milky Way is our neighborhood in the universe. It’s a galaxy and there are many others out there. Galaxies contain gas, dust, and billions of stars or more. They come in four main shapes: elliptical, spiral, peculiar, and irregular. Galaxies can collide, and grow in size by eating each other.

Crash Course Astronomy Poster:

Table of Contents
Milky Way is a Galaxy (One of Many) 2:04
Galaxies Have Four Main Shapes 3:18
Galaxies Can Collide 6:05

PBS Digital Studios:

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NGC 5363 [credit: T.A. Rector (University of Alaska Anchorage) and H. Schweiker (WIYN and NOAO/AURA/NSF)]
Panorama of Spiral Galaxy, M31 [credit: Local Group Survey Team and T.A. Rector (University of Alaska Anchorage)]
Animation of a variable star [credit: NASA, ESA, M. Kornmesser]
Hubble M31 PHAT Mosaic [credit: NASA, ESA, J. Dalcanton, B.F. Williams, and L.C. Johnson (University of Washington), the PHAT team, and R. Gendler]
Elliptical – Death of giant galaxies spreads from the core [credit: ESA/Hubble & NASA]
Spiral – HUBBLE VIEW OF BARRED SPIRAL GALAXY MESSIER 83 [credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA). Acknowledgement: William Blair (Johns Hopkins University)]
Peculiar – Colliding galaxies make love, not war [credit: NASA, ESA, and the Hubble Heritage Team STScI/AURA)-ESA/Hubble Collaboration]
Irregular – Little Galaxy Explored [credit: NASA/JPL-Caltech/STScI]
Hubble Image of Messier 101 [credit: NASA, ESA, K. Kuntz (JHU), F. Bresolin (University of Hawaii), J. Trauger (Jet Propulsion Lab), J. Mould (NOAO), Y.-H. Chu (University of Illinois, Urbana), and STScI]
A poster-size image of the beautiful barred spiral galaxy NGC 1300 [credit: NASA, ESA, and The Hubble Heritage Team STScI/AURA)]
NGC 3344 [credit: Adam Block/Mount Lemmon SkyCenter/University of Arizona]
Flocculent spiral NGC 2841 [credit: NASA, ESA and the Hubble Heritage Team]
Barred Spiral Galaxy NGC1365 [credit: SSRO/PROMPT and NOAO/AURA/NSF]
Magnificent Details in a Dusty Spiral Galaxy [credit: The Hubble Heritage Team]
Panning across Messier 77 [credit: NASA, ESA, Digitized Sky Survey 2. Acknowledgement: A. van der Hoeven]
Hubble Mosaic of the Sombrero Galaxy [credit: NASA/ESA and The Hubble Heritage Team]
Spiral Galaxy NGC 4565 [credit: ESO]
M87 (with Jet) [credit: Adam Block/Mount Lemmon SkyCenter/University of Arizona]
M59, NGC4621 [credit: NOAO/AURA/NSF]
Fulldome simulation of colliding galaxies [credit: NASA/STScI]
Antennae Galaxies [credit: ESA/Hubble & NASA]
Terzan 5 Artist’s Concept [credit: Amanda Smith, Institute of Astronomy, University of Cambridge]
Interacting Galaxy Pair Arp 87 [credit: NASA, ESA, and the Hubble Heritage Team]
Doing cartwheels to celebrate the end of an era [credit: ESA/Hubble & NASA]
Hoag’s Object [credit: NASA and The Hubble Heritage Team]
Paranal Nights [credit: Y. Beletsky (LCO)/ESO]
Tarantula Nebula [credit: TRAPPIST/E. Jehin/ESO]
Hubble Ultra Deep Field 2014 [credit: NASA, ESA]


ElfianWitch OkeyDokey says:

Can we have a space is weird shirt?

Jordan Riddle says:

this is all hdsnfhdsbkh to me

Lulu, Drinker of Coffee says:

Makes you wonder how people can still think so small.. so narrowly with reality being so infinite.

Giselle Seed says:

One common thought during my studies; the vast distances and lengths of time, the sheer mass of a black hole… all of it so far away and so different from what we are accustomed to, confined to our short life on our tiny planet, all over in the "cosmic blink of an eye", our place so small it is scarcely a single subatomic particle in this grand universe, and every time I think of it I am truly humbled, for I truly cannot conceive of its beauty and depth.

Ohwaitit'snate(and Macie) says:

I think that the ring galaxy is the product of a massive event that pushed away stars into the perfect ring form

randy95023 says:

The Hubble Space Telescope opened us up to distances and accuracy of measurement that the human mind truly cannot comprehend.  Sure, we can parrot distances in the Billions of Light Years but "knowing" is NOT "comprehending".  The human mind cannot even truly comprehend interstellar distances to our "Nearest" neighbors.  That's why our Science Fiction shows and movies use outrageously advanced technology that we can't actually comprehend either.  We will be extinct Millions of years before we reach Star Trek technology.  So cool to think about though!

Klemm Zagala says:

where do newly born star got their hydrogen fuel if the cloud they are came from where exploded stars who were composed of heavier elements?

Abdulrahim Mohamed says:

In my science textbook, it said that the 4 types of galaxies are spiral, elliptical, irregular and lenticular. But in the video, they switched lenticular for peculiar. Which is correct?

Christian Carvajal says:

my favorite thing to do with these videos is to just pause on the faces he makes

Bill Chen says:

Hey what are teh ranges of star ages in a spiral galaxy

Nathaniel Hough says:

i like the animations

schadenfreudebuddha says:

galaxy collisions…this really was a CRASH course!  sorry.

jerry bonenfant says:

i love these crash courses… simplified enough to help explain to my kids too.. thanks

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