The Universe Study Guide printable pdf download

The Universe Study Guide

ANSWER KEY

The Universe

Study Guide

1. Define galaxy

A collection of billions of stars held together by gravity

2. List and

* spiral-galaxy with a central core of stars with arms of stars

describe the 3

spiraling out from the center

types of galaxies.

* elliptical—flattened, egg-shaped groups of stars

* irregular—groups of stars that form no specific shape

3. What is the

Milky Way is our galaxy and is spiral-shaped; our solar

name and shape

system is located in one arm 2/3 the way out from the center

of our galaxy?

4. What is a star?

A celestial body made up of hot gasses that gives off energy

because of nuclear fusion

5. How do we

By temperature, size, brightness (luminosity) and color

classify stars?

6. What is a light-

Distance light travels in one year (9.4 trillion km); to make it

year and why do

easier to measure the vast distances in space

we use it?

Use the diagram

at left to answer

Main Sequence Stars

the next 3

questions.

7. Which named

Spica

star is the hottest?

8. Name the

Betelgeuse

brightest star on

the diagram.

The Universe Study Guide