Astronomy, Space, the Universe

What is existence? What is love? What is the universe?

Three interconnected ideas. Which is the most difficult to define? Remember how your mom might have once said something like: love keeps multiplying, or something like that every time she had another child and had less time for you? The universe is a little like that. It’s expanding, slowly, infinitely. That’s what some smart people think. Love, the universe, constantly expanding. Whoa, trippy.

What is existence? Well, we are here, and we are sentient life forms living on the one planet we’re aware of that is able to support life forms and thus provide us the environment for our brains to be intelligent enough to ask that simple question. What is existence?

By the way, sentient means that a being is capable of feeling and thinking.

The philosopher Rene Descartes said: Cogito, ergo sum.

I think, therefore I am.

It is the idea that the simple act of questioning one’s existence proves the reality that we have minds and therefore exist. It’s kind of a circular definition, but it sort of works. We think about existing, therefore we exist. In this universe. This expanding universe that is unfathomably big. And we are unfathomably small.

What is the universe, and how old is it, and why does it exist, and how much longer will it be around, and what’s outside of it, and…

...let’s start with the basics of the little bit we know about our tiny neighborhood called Earth. We’ll start with our solar system.

Oh, and spoiler alert: I don’t have answers for most of the questions I just asked. So let’s figure them out together.

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Astronomy 101

Introduction
Solar system
Earth
Moon
Stars
Galaxies
Origin
Formation
Smart people
Vocabulary
The future
Recommended films
Recommended books
Additional resources