University of Phoenix Material

Basics of Astronomy Worksheet

Complete the table based on the readings for this week: Ch. 1–4 of The Essential Cosmic Perspective.

Term or concept
Definition and explanation
The Universe

1. What is Earth’s Sun, and what is its role in the solar system?
2. What is the Milky Way galaxy and the sun’s position in it?
3. What is the Big Bang, and what does it say about the age of the universe?
4. What is meant by the phase “looking out in the universe is looking back in time?”
1. The earth’s sun is a star, it generates heat and light through nuclear fusion.
2. The Milky Way galaxy is the constellation that earth belongs to, the sun is just another star within it.
3. The big bang is the
19. An idealization of scientific thinking.
20. Ancient Greek philosopher, he and others claimed the earth was the center of the universe and that the earth wasn’t moving
21. The way we perceive our place in the universe.
22. He gave an answer to the four reasons that the universe was geocentric.
23. Kepler’s laws.
Seasons of the Earth

24. How does the Earth rotate, and how does that relate to day and night or the seasons?
25. How does the Earth revolve, and how does that relate to day and night or the seasons?
26. What causes the seasons? Is it the tilt of the Earth’s axis or its changing distance from the Sun throughout the year?
24. Counter-clockwise, the earth’s rotation allows the sunlight to hit parts of the earth for a period of time, which is daylight and when it’s not its night.
25. The earth revolves on its axis, which points the planet towards the sun at different angles during different seasons.
26. The tilt on the earth’s axis causes the seasons.
Gravity, Free Fall, and Orbits

27. What is gravity, and how much weaker does it get as you get farther from the center of a body?
28. Are objects in orbit of the Earth still under the influence of gravity?
29. An object in orbit falls around the Earth. What do planets, comets, and asteroids fall around?
27. Gravity is the attraction or force between masses, it gets weaker by two squared or 4.
28. Yes
29. The