Name: The New Astronomy: Crash Course History of Science #13
Uploaded: 2022-06-03T01:04:47.000Z
Duration: 12 min 35 s
Description: VoiceTubeの動画で発音を聞きながら英語表現を覚えよう！学べる英語：

Heliocentrism was central to revolution in European astronomy.

We'll follow this idea to its conclusion with Galileo.

But before we get there, there are two critical links between Copernicus and Galileo.

This is the story of Tycho Brahe and Johannes Kepler… and a violent

There are a lot of quirky characters in the

But Tycho Brahe is a true champion of quirk.

Traditionally referred to as “Tycho,” not by his last name, he was a Danish aristocrat,

born in 1546—three years after De rev dropped and Copernicus also dropped.

But maybe a little too serious about knowledge: my dude got his nose cut off in 1566 during

a sword duel with his cousin and fellow rich person Manderup Parsberg.

Their beef was—wait for it—over mathematics.

You have to really love math to lose your proboscis over it.

After the duel, Tycho had prosthetic noses made that he could attach to his face with

But whenever he got angry, he'd heat up and start sweating, and the wax would melt…

In addition to an astronomer, Tycho was an alchemist and astrologer.

He became so well known as a scientist that the Danish king kept trying to give him castles

And Tycho kept turning down castles—until he got his own private research island, Hven

On Hven, Tycho built two structures, Uraniborg, or the Castle

of the Heavens, and Stjerneborg, or the Castle of the Stars.

Together, these castles represented the most state-of-the-art research labs of the day.

He had his own printing press, paper mill, alchemical equipment, and—most importantly—huge,

expensive instruments and an army of staff scientists working for him.

In fact, Tycho worked with his younger sister, Sophie.

Tycho and his staff produced some of the most precise naked-eye observations of the night

These were roughly twice as precise as similar observations by ancient Egyptian, Babylonian,

Tycho's observations were not surpassed by those made with telescopes for a hundred years.

Tycho believed in a geo-heliocentric cosmos.

In this model, the sun orbits the earth, but the other planets revolve around the sun.

So Tycho was moving away from Aristotle and Ptolemy.

And his hybrid model actually solved a bunch of the math problems astronomers were having

But it also placed the sun on a collision course with the planets.

Even if the Tychonic model of the solar system had flaws, his observations paid off in other ways.

Tycho observed and took precise measurements of the same sky all the time, noting that

sometimes “stars” streaked around—these were comets.

In 1572, he saw a nova stella, er, a new star, which we now call a supernova.

He noted that this new star didn't have a tail or show any stellar parallax, meaning

an apparent shift in position against a background of distant objects.

This meant that the new star had to be really, really, incredibly far away—a true star

Moreover, the appearance of a new star meant that the heavens could change!

If you really believed your whole life that the heavens were perfect and unchanging, how

hard would it be to adjust those beliefs just because you saw one new dim little pinpoint

of light at night, a dot that nobody else cared about?

That's just what Tycho did: one year after the supernova, in 1573, he dropped his own

book: De nova stella, or On the New Star.

But after all that hard work, Tycho's life ended sadly.

The old Danish king died, and his nineteen-year-old son took over.

This not-super intellectual new king wanted his nobles to spend their energy on war, not science.

So he roused up opposition to Tycho's science castles, whipping up a mob to drive the patient

Thus Tycho moved to Prague, in the Holy Roman Empire—where he died after only two years

in exile, leaving behind an enormous meticulously detailed catalogue of observable stars and

Johannes Kepler was born in 1571 near Stuttgart, Germany.

His grandfather was rich, but his dad hadn't done so well, dying as a mercenary in the

Little Joey went to school on scholarship at a Latin school, seminary, and then the

Then, in 1600, Kepler so impressed Tycho that the older astronomer shared his secret data

sets with him, and the two become close collaborators.

Then politics happened: Kepler, a devout Lutheran, was told to convert to Catholicism or leave

Kepler—who used to call himself a “mangy dog” because he was so full of self-doubt—chose exile.

When Tycho died in 1601, however, Kepler was immediately ordered to serve as the official

imperial mathematician and continue Tycho's work.

As imperial numbers person, Kepler mostly provided the emperor with advice about astrology.

Remember that astronomy was seen as the less useful, theoretical cousin of the practical

But Kepler, thank goodness, kept making time for astronomy.

In addition to the observing and cataloguing that he'd done with Tycho, Kepler worked

And he observed a new supernova in 1604, in the foot of a constellation that is supposed

to depict a Greek dude fighting a giant snake!

Kepler wrote his own De nova stella around 1605.

But Kepler is famous thanks to the laws governing how planets move.

Kepler published Astronomia nova, or A New Astronomy, in 1609.

This mind-zapper of a tome came from a decade of looking at Mars to figure out mathematical

formulas that could predict its movements.