vocabulary

3. a moon phase that looks like less than half a circle from earth
4. a planet outside our solar system
7. a moon phase that looks like a full circle from earth
10. the relative size of things
11. the nearly circular path a smaller object (like the moon) travels around a larger object (like earth)
12. the amount of time it takes for a planet to complete one orbit around a star or stars
14. the sun, the planets that orbit the sun, and other objects that orbit the sun
15. to shine light on an object and make it visible
16. a moon phase in which the moonis not visible from earth
17. a moon phase that looks like more than half of a circle from earth

1. an object, diagram, or computer program that helps us understand something by making it simpler or easier to see
2. something we observe to be simular over and over again
5. eclipse when the moon is completely dark
6. a moon outside our solar system
8. the shape of the illuminated part of the moon as it appears from earth
9. a moon phase that looks like half-circle from earth
13. the border between light and dark on the moon
14. the star that is the main source of light at the center of our solar system
18. a rocky sphere that travels around a planet