The Universe Review

Star Life Cycle

100

Which type of star ends its life cycle in the form of a neutron star or a black hole?

High-Mass Star

200

• At the end of its life cycle, a high-mass star sometimes leaves behind an invisible object in which gravity is so strong that radiation cannot escape. What do we call this object?

Black Hole

300

• Which stage in the life cycle of a high-mass star is characterized by the star collapsing and throwing its outer layers into space?

BOO!

Super Nova

400

• What process occurs throughout most of a star’s lifetime?

Nuclear Fusion

500

What kind of star becomes a giant when fusion slows down, the outer atmosphere of the star expands, luminosity increases, and the star begins to fuse helium into carbon?

Low-Mass Star, Main Sequence Average Star

Structure of the Universe

100

• One way to compare the objects in space is by their relative sizes. Which of the following correctly lists the objects in space in order from largest to smallest?
• A. universe, galaxy, star, planet
• B. universe, galaxy, planet, star
• C. galaxy, universe, star, planet
• D. galaxy, universe, planet, star

• A. universe, galaxy, star, planet

200

• What are located between galaxies?

Voids

300

• A galaxy contains stars, gas, and dust. This matter must be held together or the galaxy will break apart. What is responsible for holding the stars, gas, and dust together in a galaxy?

Gravity

400

Which of the following is part of the universe?

A. all existing energy

B. all existing matter

C. all existing space

D. all existing energy, matter, and space

D. all existing energy, matter, and space

500

What do scientists compare the universe to when describing the shape and location of galaxies and voids?

Soap Bubbles

Vocabulary

100

• What is the term for a celestial body made up of gases that can give off light?

Star

200

• What term is used to describe several planets orbiting a star?

BOO!

Solar System

300

A large, cold cloud of gas and dust in interstellar space.

Nebula

400

A large group of stars, gas, and dust bound together by gravity.

Galaxy

500

A measure of the brightness of stars as they appear to an observer on Earth.

Apparent Magnitude

Star Characteristics

100

An astronomer uses a telescope to observe a star. She observes that the color of this star is similar to the color of the sun. Using this information, what can the astronomer guess about the star?

A.The star is hotter than most other stars in our galaxy.

B. The star and the sun have similar size and surface temperatures.

C.The star is becoming a black hole because its core has collapsed.

D.The star is a white dwarf because nuclear fusion in the star has stopped.

B. The star and the sun have similar size and surface temperatures.

200

• What characteristic of stars can be measured using luminosity?

Brightness

300

Which type of magnitude does luminosity describe?

Absolute Magnitude

400

Fill in the blanks:

A white dwarf is                           but                    than the sun.

BOO!

Hotter, Dimmer

Hotter, Smaller

500

How is it possible for a star that is actually dimmer than another star to appear brighter to an observer on Earth?

Because it is closer to Earth so the apparent magnitude is greater. Distance

Hertzsprung-Russell diagram

100

• What features of stars are plotted on the Hertzsprung-Russell diagram?

Luminosity and Temperature

200

• Which of the following statements does not accurately describe the Hertzsprung-Russell diagram?
• A.         Bright stars are located at the top of the diagram.
• B.         Dim stars are located at the bottom of the diagram.
• C.         Hot stars are located on the left side of the diagram.
• D.         Cool stars are located on the left side of the diagram.

• D.         Cool stars are located on the left side of the diagram.

300

What band on the HR-Diagram represents the area where most stars live their life?

A. the upper-left quadrant

B. the lower-left quadrant

C. the upper-right quadrant

D. the diagonal band that runs from the upper-left to the lower-right

D. the diagonal band that runs from the upper-left to the lower-right

400

If a star is located in the top left corner of the HR-Diagram, what is their temperature like?

BOO!

>25,000^oC or 11,000-50,000 K

500

What percent of stars are in the main sequence stage of life and why?

BOO!

90% because stars spend most of their lives in this stage.