Welcome to Introductory Astronomy! Imagine stepping outside on a clear night and looking up at a sky filled with thousands of glittering points of light. Humans have gazed upward in wonder for countless generations, searching for patterns, stories, and meaning in these distant beacons. Astronomy is our way of understanding those bright dots, how they were formed, and how we fit into the universe surrounding us.

In this introduction, we’ll start by familiarizing ourselves with some of the most essential concepts in astronomy, from identifying constellations to understanding the planets' motions and stars' life cycles. You’ll learn how astronomy isn’t just about staring through a telescope—it’s about asking questions, collecting evidence, and discovering the beauty and complexity hidden in the night sky. By the end of this section, you’ll have taken your first steps on a journey that connects you with observers from ancient civilizations to the scientists working at the cutting edge of modern research today. Let’s begin with a preliminary bit of math.