This is CBS I Am The World. I'm John Bachelors with Matthew Schindel. The space historian,

curator at the Smithsonian National Air and Space Museum, a really cool job, and the book

is really cool. For the love of Mars, it's about human history and the Martian planet,

projections, interpretations, and now science. Matt Descartes died 1650. Christian Hoygens,

Giovanni Cassini died 1712. Isaac Newton died 1726. These men, Leonardo Euler of all physics,

these men put together what we understand to be science. Following Galileo's groundbreaking

martyrdom to what he saw through the telescope, all of this is going on simultaneously

with them inheriting the old world. Were they seen as rebellious of the ancients when they

provided these interpretations of observation and mathematics? I think yes and no, right?

Galileo didn't see himself necessarily as being rebellious. He thought he was still

working within that same tradition, but trying to modernize it based on new observations,

new mathematics. I don't want to try to get too deep into what Galileo really thought he was

doing, but at least this is the way that he would describe it in letters that he wrote to his patrons.

Galileo's observations of the moon certainly gave people a reason to think that there

was something different going on in the heavens than what they inherited from Aristotle.

There did seem to be the need for some new ways of thinking about the solar system, but the truth

is that there were multiple models of the universe circulating at that time, each kind of not

seeming perfect, not being the obvious choice for what was happening. You had the old

Aristotelian model, the Tomeic model, with the Earth at the center. You then had

Tycho Brahe's model where you had the Earth at the center, but everything else but the moon

orbiting around the sun. Then finally you had this Copernican model, which was great, mathematically,

but it still didn't really line up perfectly with observation. We have this period

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