When the idea of a sun-centered or heliocentric universe first started to arrive on the scene in the late

1500s and early 1600s in Europe, there was a very reasonable objection to the idea.

And this objection came from Tyco Brahe, perhaps the greatest astronomer to ever live,

at least according to Tyco Brahe.

And he said, look, let's say we live in a solar system, cute name, by the way, for this setup.

And the Earth revolves around the sun.

That means over the course of a year, the Earth changes position by over 180 million miles.

During the summer, we're on this side of the solar system, during the winter, we're on the opposite side.

That's a big difference.

That means if I look at a

distant star from these two vantage points, then the position of the star on the sky should

slightly change because I'm looking at it from these vastly different reference points. And so

he went out to perform that measurement and found no shift in position with the stars at all.

And he was the world's greatest astronomer.

So if anyone's going to do it, it's him.

And so he said, look, I understand mathematics and that we have one of two situations,

this lack of observation of the shift of the positions of stars.

This either means that the Earth is the center of the universe, in which case over the seasons,

you will never see a shift because you always have the same perspective. Or, you know, we could

live in a sun-centered universe, a solar system, a heliocentric universe.

But in order for this to be true, the stars have to be so far away that it's impossible for me,

the world's greatest astronomer, to measure a shift in their position.

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