Class is in session.

And today's topic is a big one.

And not big as in an exceedingly long episode, but big as in large, very large, the largest of the largest,

the biggest of the bigs, the grandest of the grands, the whole entire universe.

In this Astro 101 series, we've gone from the basics, like pointing and stuff on the sky, to exploring

planets and stars and galaxies, and now we are going extreme. We're going to talk about

cosmology. Now, as you might have guessed from the number of episodes of this podcast devoted to the subject, cosmology, is near and dear to my heart.

Because I consider myself, when I do think about myself and try to categorize myself, as a cosmologist, cosmologist, cosmologist, cosmology, the study of the cosmos, of the heavens,

of the universe. Cosmology is the branch of astrophysics, which is the branch of physics, which is

the branch of science, which is the branch of philosophy, that studies all of it.

On big scales, we're talking about the history of the universe, the origins of the universe,

if that even has meaning, but we'll get to that, the contents of the universe, the evolution

of the earth, the fate of the universe.

It's about the universe in general, and this is the most general of generals, it's a story of cosmology,

and not just any cosmology, which has been done for millennia by all sorts of people for

all sorts of reasons, but physical cosmology.

Physical cosmology is, you've probably guessed, the story of the universe based on

science. But cosmologists are attempting to answer all the same questions that everyone has been

trying to answer since the beginning of being able to ask questions. Why are we here? What's our place in the universe?

Buy my book.

How does it all fit together?

These are questions that people have been asking forever

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