Module 1: What is Astronomy?

AstronomyUnderstanding humans' place in the universe has been an ongoing quest for scientists. Astronomy is the study of the Earth and all of the material in the universe. Astronomers search out answers about the mysteries of the unknown.

You are already an astronomer in a very simple sense. Each day, you are affected by the movement of the Earth causing day and night. If you have ever asked, “What is the reason for day and night?” you are acting like an astronomer. If you have ever wondered what causes the seasons, you are acting like an astronomer. You may wonder, why there are 365 days in our calendar year. Once again, you are acting like an astronomer.  The night sky is a source of wonder. The companion to the Earth, the Moon, also influences your life, even though you may not realize it yet. Although you may not know the patterns, you have observed the celestial bodies above such as stars, planets, comets, and nebula. That is what astronomers do, and that is what makes you a sort of astronomer, too. 

Getting Started

Astronomy Terms and Concepts Playerself-check iconBefore you begin your own journey through the study of the Universe, check to see if you already know some astronomy terms and concepts by completing this interactivity. Read each definition, and drag and drop the correct term into the blank provided. Then, click SUBMIT to check your response. Click the player to begin.

 

Key Vocabulary

Glossary icon
To view the definitions for these key vocabulary terms, visit the course glossary.

anteumbra galaxy planet summer solstice
aphelion hypothesis precession synchronous rotation
astronomical unit independent variable problem tilt
autumnal equinox light-year procedure umbra
celestial sphere lunar eclipse revolution universe
constants Milky Way Galaxy rotation vernal equinox
control nadir qualitative date waning
data observation quantitative data waxing
dependent variable parsec scientific notation winter solstice
eclipse penumbra solar eclipse zenith
experiment perihelion Solar System  
field of view phase star