Unit 1: Space Systems Test

3. Used his telescope to prove the heliocentric model of the universe
6. Who discovered that galaxies moving fastest are located farther?
8. The resulting force of gravity when the distance between two objects is doubled would be ___ ___.
9. The one property of a star that determines the rest of its life cycle.
11. Hubble's Law implies the universe is doing this.
12. The change in frequency or wavelength of a wave for an observer who is moving relative to the wave source
14. used his telescope to see the moon craters, the moons of Jupiter, and the sunspots on the sun
16. How our Sun will eventually end its life cycle.
18. The products of hydrogen fusion inside a star are helium and this.
21. The reason Earth's gravity is stronger than the Moon's is because of the Earth's ____.
23. Kepler’s First Law of Planetary Motion states that a planet’s orbit has this shape with the sun at one foci
26. Instrument that separates light into individual colors/wavelengths
27. Oval shape centered on two points instead of one point
28. He developed the Law of Universal Gravitation and the 3 Laws of Motion
29. The two variables determining the strength of gravitational pull are mass and this.
30. The layer of the sun where fusion occurs.
31. The type of relationship between a galaxy's velocity and its distance according to Hubble's Law.

1. a model designed to explain what we see in the sky while having the Earth located in the center of the universe
2. This man developed the 3 laws of planetary motion (ellipses, etc.)
4. Your weight on the Moon would be this compared to your weight on Earth.
5. Motion of a planet moving in the opposite direction of the normal direction of planetary motion as observed from Earth
7. The possible final remnant of a very high mass blue main sequence star after a supernova.
10. All of which element in the universe originated from the Big Bang.
13. A process where the nuclei of two atoms combine to form a larger nucleus.
15. The key difference in conditions during formation that explains why inner and outer planets are different.
17. This form of energy has the longest wavelength and lowest frequency.
19. the point in a planet’s orbit where the planet moves with the greatest speed
20. Unit of measure that is the average distance between the Sun and Earth (150 million km or 93 million miles)
22. Theory supported by cosmic background microwave radiation
24. Used epicycles to explain the retrograde motion of the planets in his geocentric model of the universe
25. proposed a model of our solar system with the Sun in the center instead of the Earth at the center