Terence Tao

And so he had all this data which Kepler could use to confirm his theory.

And so Kepler started working with Tycho, but Tycho was very jealous of the data.

He only gave him little bits of it at a time.

And I think Kepler eventually just stole the data.

He copied it and had to have a fight with Brahe's descendants.

But he did work out, he did get the data, and then he worked out to kind of his disappointment that his beautiful theory didn't quite work.

Like the data was sort of off from his platonic solid theory by about 10% or something.

And he tried all kinds of fudges, moving the circles around and things.

It didn't quite work.

But he worked on this problem for years and years.

And eventually he figured out how to use the data to work out the actual orbits of the planets.

And that was an incredibly clever, genius amount of data analysis.

And then he eventually worked out that the...

They also actually ellipses, not circles, which was shocking for him.

And then he worked out the two laws of planetary motion, ellipses, also equal areas, sweep out equal times.

And then 10 years later, after collecting a lot of data, the furthest planets like Saturn and Jupiter were the hardest for him to work out.

But then he finally worked out this third law also that...

that the orbits, the time it takes for a planet to commit its orbit was proportional to some power of the distance to the sun.

And these are the three famous laws of motion.

And he had no explanation for them.