Introduction to the Solar System: Crash Course Astronomy #9

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In today’s Crash Course Astronomy, Phil takes a look at the explosive history of our cosmic backyard. We explore how we went from a giant ball of gas to the system of planets and other celestial objects we have today.

This episode is sponsored by Squarespace:

Makeup of a Solar System 2:38
From Gas to a Disc 5:36
Planet Formation Depends on Distance to Sun 7:14
Motion of a System 8:21

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Sun: [credit: NASA/ESA]
Jupiter: [credit: NASA/ESA]
Geocentric celestial spheres; Peter Apian’s Cosmographia (Antwerp, 1539):
Mercury: [credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington]
Understanding Solar System Dynamics: Orbits and Kepler’s Laws (2008):
Saturn: [credit: Photo by NASA/JPL/Space Science Institute/Gordan Ugarkovic]
Neptune: [credit: JHUAPL/SwRI/Dan Durda]
Bennu’s Journey:
Artist’s impression of a protoplanetary disk:
Rocky Ring of Debris Around Vega: [image credit: NASA/JPL-Caltech]
Proplyds in the Orion Nebula:


Sir Redbeard says:

But Australia is not a continent… It is in Oceania

Ashley Fernandez says:

Planets are big enough to be round and most importantly they orbit stars unlike Ganymede that orbits Jupiter which is probably not a star.

Mare Van Hove says:

A good thing to learn more about the first part: the movie Agora.

Stalkerhunter Araya says:

I was wondering if there were experiments done in the ISS about rock formations in zero gravity turning into planets?and if so any1 can give me a link to the experiment that gives of a result the size of basketball already

michael w says:

math and science explain the reason behind the BELIEF of the big bang… it has never made a big bang.

you all think the bible is a make believe system… has anyone seen a big bang?

it makes sense… but there is no proof

michael w says:

People say there is no CREATOR because they DON'T WANT to understand HIM.

When mere men do things the world can't explain, it's most often excused.
It's considered understandable; it's made allowable…

…But GOD, our CREATOR is not allowed to do things too elusive to understand??? .

People think there is no CREATOR because they CAN'T understand HIM.
Narcissism disables wisdom.

pizzacrusher says:

If the Sun is 98% of the mass of the solar system, why is it all hydrogen and helium? I figured it would have 98 % of all the Iron and Nickel and Silicates and Zirconium etc etc etc… too? how did all the hydrogen and helium find its way to the center of the disk? Even we look at the gas giants (the planets) I thought their atmospheres were like ammonia or methane or something, not Hydrogen and Helium. This confuses me!

Lemon Lime Doesn't Rhyme says:

i love this man

J.O.W.S Designs says:

I would think that a planet has to 1. Orbit around a star and not another rocky or gas object 2. Have to be above a certain diameter

luxcythewolf says:

the earth is blue and there is nothing i can do

Killkor says:

Hey! I'm not dense!

I'm highly compacted. 🙂

IceEagleA5 says:

The Enterprise-E AND the Falcon?!

I have not felt this presence in a long time.

Ryougi Shiki says:

Wee baby sagan spotted!

Nikki Reyes says:

this is so good!

Jensen McRae says:

astronomy midterm tomorrow, everyone pls send good vibes D:

Minghui Liu says:

The captions use the word "disk", which should be "disc".

Thomas Lee says:

Pluto is not considered a planet because it does not fit condition 3: a planet must be able to clear other celestial objects out of it’s orbit.

Ram Kumar says:

Hi Phil, i got quite an answer for what is inertia in my dream last night.
"""Inertia is the Resistance offered by "spacetime" fabric around object which is being disturbed."""
by disturbance i mean anything that change the state of object. it qualifies with all phenomena related to inertia, upto my knowledge level..
what would you like to say about this?

Anselma Reich says:

The mongol astronomer kills me. XD

Michael W says:

Jerry Smith anyone?

Adam Ireland says:

Australia isn't a continent. Australasia is.

Riley Berman says:

The Earth is flat. You are listening to government propoganda! Feed the rebellion! JK

Mr.Cake says:

I thought we are the solar system and everything else is a star system. There is only one sun, and that is the sun we have, everything else is a star system. Tell me if I'm wrong but that's what I thought.

Allen Pagano says:

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