Definition: astronomy: The scientific study of matter in outer space, especially the positions, dimensions, distribution, motion, composition, energy, and evolution of celestial bodies and phenomena.
astronomy
From Nick Greene, About.com Guide
Free Email Courses
Explore Space / Astronomy
Must Reads
About.com Special Features
A Smarter Future
Tips that will help finance your education, excel in the classroom, and advance your career. More >
How to Ace the GRE
Being well prepared is the first step; here are more essential suggestions. More >
©2009 About.com, a part of The New York Times Company.
All rights reserved.