Across
- 3. This person was presenting arguments for Earth's spherical shape based off of naked-eye observations (page 37).
- 5. Improvements in telescopes led us to find dim, fuzzy patches of light, known as _______, which turned out to be external star systems similar to the Milky Way (page 57).
- 7. This model of the universe places Earth at the center of the universe with all other bodies revolving around it.
- 9. This astronomer was the first to find the heliocentric model of the Sun and the planets.
- 13. The apparent size of an object relative to another object(s) is known as this (2 words).
- 16. This mathematician was the first to say teach others that the Earth is spherical (page 37).
- 17. When Kepler saw moons through a telescope, he called them ______ because he thought of them as attendants or bodyguards. (page 54)
- 19. Galileo found this planet had blobs off the edge, which would later be discovered by another astronomer that these are the rings of this planet.
- 20. The number of laws Kepler coined from his work.
Down
- 1. This model puts the Sun at the center of the planets' motion.
- 2. This person used the size of the Earth's shadow on the Moon during a lunar eclipse to estimate the relative size of the Earth and Moon. (page 39)
- 4. This astronomer discovered that orbit paths are ellipses, not circles.
- 6. This astronomer, in the late 1500s, not only recorded planetary motions but also used an exploding star to show that stars are farther away than where planets move. (page 51)
- 7. This famous astronomer was one of the first to use the new invention of a telescope to study astronomical objects. (page 54)
- 8. This kind of motion is associated with a planet that will move west with respect to the stars. It also means "backward."
- 10. The apparent shift in position of a foreground star relative to the background is known as the star's _________.
- 11. This astronomer, who is arguably the greatest scientist of all time, used his research to pioneer the studies of motion, optics, and most importantly, gravity.
- 12. This person, from Egypt, fashioned a model of planetary motions in which each planet moved on one small circle, which in turn moved on a larger one, known as an epicycle. (page 47)
- 14. The actual shape of an orbit, instead of a circle.
- 15. To describe an ellipse's shape, astronomers usually report this, which indicates how far from the center of an ellipse each focus is located. (page 51)
- 18. Galileo found this planet to go through a cycle of phases jus like the Moon.