H-R Diagram Quiz

By studying the H-R diagram one can conclude that in many stars, as temperature increases, brightness increases. Which of the following additional factors affects luminosity?

• Age

• Color

• Distance

• Size

Ejnar Hertzsprung and Henry Norris Russell were astronomers in 1915. They developed the H-R diagram by making a graph showing the color of the stars compared to their luminosity (brightness). They plotted thousands of stars to make the graph. The graph could answer some questions but not others. The graph below shows an early H-R diagram. What question could NOT be answered by using this H-R diagram?

• What is the luminosity of most red-orange stars?

• Where are most blue stars located on the graph?

• Are most stars in a line from bright blue to less bright red?

• Why were so many places on the graph where there are no stars?

Lauren and Jamal are using a telescope to look at the night sky. They study two stars that appear next to each other and shine with about the same amount of brightness. Lauren tells Jamal that the two stars must have very similar characteristics. Which other statement may explain why the two stars are equally bright?

• One of the stars may be a different color than the other.

• One of the stars may be larger, but closer than the other.

• One of the stars may put out less energy but be closer than the other.

• One of the stars may put out more energy but be closer than the other.

One evening, Leslie is observing the stars in the constellations Ursa major, also known as the Big Dipper. She wonders if all the stars that make up the constellation have the same surface temperature. The next day, she stops in the school library to find a book on stars to help her answer her question. Which of the following characteristics will Leslie use to determine a star’s surface temperature?

• Size

• Color

• Shape

• Apparent brightness

Krista is creating a model to show the sequence of our Sun’s life cycle. She has already included the nebula stage and the main sequence star stage. Which stage should she include next?

• Black Hole

• Red Giant

• Supergiant

• White Dwarf

Tags

NGSS.HS-ESS1-1

A constellation is a group of stars that appear to form a pattern. The photograph below shows seven stars of a constellation called Ursa Major. Based only on the photograph, how do the seven stars in the constellation compare to the other stars?

Which star has the highest temperature?

• Bellatrix

• Vega

• Aldebaran

• Betelgeuse

Canopus is farther from Earth than Arcturus. Why does it appear brighter to a viewer on Earth than Arcturus?

• A. It reflects more visible light.

• B. It has greater absolute brightness.

• C. It emits light that travels at greater speed

• D. It emits more infrared and ultraviolet light.

The brightness of a star depends on how much light is released by the star and how far the star is from Earth. There are two ways to describe a star's brightness. A star's brightness is the brightness seen by humans on Earth. A star's ________ brightness is its actual brightness and does not depend on where the star is viewed from. Which of the following correctly completes the sentence above?

The diagram shows Earth in its yearly orbit around the Sun. During the year, places in the Northern and Southern Hemispheres experience seasons because of the tilt of Earth’s axis.

Tags

NGSS.MS-ESS1-1

NGSS.MS-ESS2-6