Basic Astronomy Terms
Enter the number from the column to the left into the text box next to the appropriate word in the right-hand column.
1. an explosion that scientists believe occurred at the beginning of our universe; it is thought that after this explosion the first celestial bodies formed space
2. the tendency of a body at rest to stay at rest, and of a body in motion to stay in motion, unless acted upon by another force celestial body
3. the relatively empty area between and around stars, planets, and other celestial bodies parsec
4. the force of attraction between all objects light year
5. a star and all of its satellites solar system
6. a natural object surrounded by the vacuum of space gravity
7. the area containing all matter, energy, and space The Big Bang
8. unit of distance equal to 3.26 light years universe
9. the path a satellite travels around a larger object satellite
10. the average distance from the earth to the sun (about 93 million miles; or 149.6 million kilometers) orbit
11. an object (natural or manmade) that is held by gravity and inertia in a circular or elliptical path around a larger object inertia
12. the distance light travels in one year (about 5.88 trillion miles; or 9.45 trillion kilometers) astronomical unit



Note: this website only uses cookies for session identification. However, we do not use crackers on this website. Not that there's anything wrong with crackers, but after one or two session cookies, we really don't need the extra calories.