Chapter 21 - Section 4 - Star Systems and Galaxies

Question 1

What is a star system?

Answer 1

groups of two or more stars

Question 2

What are the major types of galaxies?

Answer 2

spiral

elliptical

irregular

Question 3

How do astronomers describe the scale of the universe?

Answer 3

using scientific notation

Question 4

binary star

Answer 4

A star system with two stars.

Question 5

eclipsing binary

Answer 5

A binary star system in which one star periodically blocks the light from the other.

Question 6

open cluster

Answer 6

A star cluster that has a loose, disorganized appearance and contains no more than a few thousand stars.

Question 7

global cluster

Answer 7

A large, round, densely-packed grouping of older stars.

Question 8

galaxy

Answer 8

A huge group of single stars, star systems, star clusters, dust, and gas bound together by gravity.

Question 9

spiral galaxy

Answer 9

A galaxy with a bulge in the middle and arms that spiral outward in a pinwheel pattern.

Question 10

elliptical galaxy

Answer 10

A galaxy shaped like a round or flattened ball, generally containing only old stars.

Question 11

irregular galaxy

Answer 11

A galaxy that does not have a regular shape.

Question 12

quasar

Answer 12

An enormously bright, distant galaxy with a giant black hole at its center.

Question 13

universe

Answer 13

All of space and everything in it.

Question 14

scientific notation

Answer 14

A mathematical method of writing numbers using powers of ten.

Question 15

What type of galaxy is the Milky Way?

Answer 15

spiral

Question 16

Suppose astronomers discover a galaxy that contains only old stars. What type of galaxy is it likely to be?

Answer 16

elliptical