Astronomy

4. light The small portion of electromagnetic radiation that humans can see with the unaided eye.
7. phase Any portion of the illuminated moon visible from earth during a month.
9. year The distance light travels in one year.
10. Way Galaxy The galaxy we live in. Contains our sun and planets.
11. An instrument used to view the different colors of light produced by different sources.
14. spectrum The range of electromagnetic waves placed in order of increasing frequency and decreasing wavelength.
15. To turn on an axis.
16. A collect of millions of stars held together by gravity.
17. tide Strong tides that occur during the full and new moon.

1. The rise and fall of large bodies of water due to the pull of gravity.
2. To orbit a central point.
3. A word used to describe an object that can be seen because it reflects light.
5. The amount of light an object emits or gives off.
6. unit A unit of measurement used in astronomy. Equal to the distance from the earth to the sun.
8. tide Weak tides that occur during the quarter moon phase.
12. Russell Diagram A graph of star’s luminosity and temperature / color.
13. Bang theory Theory that states that the formation and expansion of the universe resulted from an initial explosion.