Unit 1: Space Systems Review

6. A massive ball of gas that emits light due to nuclear fusion.
9. Kepler’s Second Law states that a line connecting a planet to the Sun sweeps out equal what in equal time intervals?
10. Kepler’s First Law states that planets move in this shape around the Sun, with the Sun at one focus.
11. Range of all types of electromagnetic radiation.
13. Kepler’s Third Law states that the farther a planet is from the Sun, the longer its what will be?
16. EM radiation with shorter wavelengths than visible light; causes sunburns.
18. Instrument used to collect and magnify light from distant objects.
20. Shortest wavelength, highest-energy radiation.
23. Theory that planets formed from a spinning disk of gas and dust around the young Sun.
24. Long-wavelength EM waves used by the WMAP and Planck telescopes.
25. Only part of the electromagnetic spectrum humans can see.
27. Number of waves that pass a point in one second.
28. Distance from one crest of a wave to the next.

1. Change in wavelength due to motion toward or away from an observer.
2. All of space, time, matter, and energy.
3. Leftover radiation from the early universe.
4. High-energy waves used in medical imaging.
5. Bright or dark lines found in a spectrum.
7. EM radiation we feel as heat.
8. When wavelengths from a star stretch longer because the star is moving away.
12. Distance light travels in one year.
14. Positively charged particle in the nucleus of an atom.
15. Reaction in stars that produces energy and light.
17. When wavelengths shorten because a star is moving toward us.
19. Tool used to separate light into its wavelengths so we can study it.
21. Scientist who proposed a heliocentric model with the Sun at the center of the solar system.
22. Observation that galaxies farther away from us are moving faster, showing the universe is expanding.
26. Astronomer who observed Jupiter’s moons and phases of Venus, providing evidence for the heliocentric model.