8 8 Lecture 3 18 The Grand Tack 16 11

This is a lecture video taken from Mike Brown's online course "Science of the Solar System. If you are interested in this excellent and free course, please check www.coursera.o...
This lecture is about the Grand Tack and the Nice Model, the migration of both Jupiter and Saturn in the early Solar System.

[@jasongill6547]

This is a great video. Thank you. I've been looking for something that was more than a documentary explanation but something less than a graduate lecture. I guess your video is the goldilocks zone of information.

[@rursus8354]

A tack is a turn of a sailing boat from having the wind from port to starboard or from starboard to port when beating. It turns direction like Jupiter turned direction.

[@Tonyv1951]

Thank you for this video. I now feel that I have a handle on how and why Jupiter stirred up the inner solar system. I never had any understanding of that issue before. I came to this place while trying to understand how Earth's water was delivered to it in the Late Heavy Bombardment by asteroid type objects, destabilised by Jupiter's migrations. One looks at the massive Jupiter and shakes one's head at the improbability that such a colossal body could alter its orbit. Your elegant description of differential torques applied by vast gas fields out beyond Jupiter and in the inner solar system, gives the likely answer.

[@laurachaves1825]

Awesome explanation, way better than my astrophysics class lecture

[@davidcanfield883]

This theory very much like "Symbols of an Alien Sky". This video postulates that these orbits were observed by ancient humans and accounts for much of their petroglyph symbology with carryover to modern times. Also, "Thunderbolts of the Gods" discusses the plasma displays and electrical discharges that would have been visible to the ancients with these planetary orbits and such is represented in their myths and sybology. Both on YT.

[@RobertWF42]

Some of the oligarchs were scattered inwards into Russia, then more recently outwards through windows.

[@cikgunirmell6958]

Amazing thank you!

[@twothreebravo]

1 person is still upset about Pluto.

[@karmanline2005]

Thanks. Can the GT also explain the tilt between solar axis and ecliptic?

[@jari2018]

What about Thea - the mars sized planet that collided with early earth , Just how many moon sized or mars sized object have might been ejected and now on 10 000 or longer cometlike orbits - We think they there migth be noone but im shure there are or do a planet 9 throw a spanner in the works

[@Tonyv1951]

I think the changing orbits of Jupiter and Saturn are the likely answer in that their passage inwards and outwards would have scattered smaller rocky bodies causing them to collide with one another (Thea and Proto Earth). I came here seeking an explanation of how Earth got its water from the bombardment of icy asteroid type materials in the Late Heavy Bombardment. This lecture really explains how Jupiter and Saturn migrated large distances inward and out again. I thought it was a very worthwhile use of twenty minutes.

[@wellardbr]

Why is the audio so low? One needs to strain to hear clearly. And does he say "oligarchs"?

[@johndorias]

So conservation of momentum is not a thing. Got it ;)

[@problemsolver3254]

Rust free plastic

[@magiccat4316]

Mars is too small

[@elisespruit5400]

Too small for what?

[@karmanline2005]

Keeping hold of a dense atmosphere?