EMS vocab

1. an object, diagram, or computer program that helps us understand something by making it simple or easier to see
3. the relative size of things
4. moon a moon phase that looks like like a full circle from the earth
8. a moon phase that looks like less that half a circle from earth
10. the sun, the planets that orbits the sun, and other objects that orbits the sun
11. the shape of the illuminated part of the moon as it appears from earth
14. a moon phase that looks like more that half a circle from earth
15. something we observe to be similar over and over again
16. the nearly circular path a smaller object(like the moon) travels around a larger object(like earth)
17. a moon phase in which the moon is not visable from earth
19. a planet outside our solar system

2. when the moon is completely dark
5. a rocky sphere that travels around a planet
6. the border between light and dark on the moon
7. to shine light on an object and make it visible
9. a moon outside our solar system
12. the star that is the main source of light at the center of our solar system
13. a moon phase that looks like half circle from earth
18. the amount of time it takes for a planet to complete one orbit around a star of stars