HR Diagram

EMS- 5.6 HR Diagram Part II

By: Ms. Bailey*

​Lesson Objective: KWBAT interpret the H-R diagram to classify stars based on their spectral class, luminosity, and temperature.

​

​TEKs:

8.8(A)  describe components of the universe, including stars, nebulae, and galaxies,  and use models such as the Hertzsprung‐Russell diagram for classification​

​Lesson Vocabulary:

1. ​ H-R diagram: used to classify stars by their luminosity, temperature, and spectral class.

​2. main sequence: a series of star types to which most stars belong, represented on the H-R diagram as a continuous band extending from the upper left (hot, bright stars) to the lower right (cool, dim stars).

3. ​ supergiant: a very large star that is even brighter than a giant, but is relatively cool.

4. ​Giant: a star that is larger in size and luminosity than main sequence stars.

5. ​white dwarf: small, dense, and hot whitish star of low luminosity

Multiple Choice

what is the H-R Diagram?

• used to classify stars by their luminosity, temperature, and spectral class.

• used to classify stars by their luminosity.

• used to classify stars by their spectral class.

• used to classify stars by their temperature,

Multiple Choice

What is a main sequence star?

•  a series of star types to which most stars belong, represented on the H-R diagram as a continuous band extending from the upper left (hot, bright stars) to the lower right (cool, dim stars).

•  a series of star types to which most stars belong, represented on the H-R diagram.

•  a series of star types to which most stars belong, represented on the H-R diagram as a continuous band extending from the bottom left (hot, bright stars) to the upper right (cool, dim stars).

Multiple Choice

What is a super giant?

• a very large star that is even brighter than a giant, but is relatively cool.

• a medium star that is even brighter than a giant, but is relatively cool.

• a very small star that is even brighter than a giant, but is relatively cool.

Multiple Choice

What is a giant?

• a star that is larger in size and luminosity than main sequence stars.

• a star that is small in size and luminosity than main sequence stars.

• a star that is medium in size and luminosity than main sequence stars.

Multiple Choice

What is a white dwarf?

• small, dense, and hot whitish star of low luminosity

• medium, dense, and hot whitish star of low luminosity

• large, dense, and hot whitish star of low luminosity

​Exploring a Hertzsprung-Russell Diagram

There are many different types of stars in the universe.  During the late 1800’s and early 1900’s, many scientists were using telescopes to classify stars.  They noticed that there was great variation in the brightness and color of  stars.  Spectroscopes, which split white light into component colors (visible light from the EMS) like the rainbow, were used to further classify stars into spectral classes (patterns of color distribution).  A relationship between spectral classes, surface temperature and star brightness was revealed.  This relationship can be seen on the Hertzsprung-Russell Diagram or H-R Diagram.

You will be creating our own HR Diagram!

​Pull Out Your Handout!

Lets get ready to learn how to read the HR Diagram

Multiple Choice

COMPLETE WITH MRS. BAILEY!!!

The Hertzsprung-Russell diagram shows how the sun is classified among the stars. A star that is several thousand times brighter than the sun with a temperature lower than 4,000 K would be classified as —

• a main-sequence star in spectral class B

• a supergiant in spectral class K

• a main-sequence star in spectral class K or M

• a white dwarf in spectral class B

​FIND A PARTNER!!

Make sure you have the worksheet we just completed

Multiple Choice

what information is found on the x-axis of the HR Diagram?

• temperature; left is hottest and the right is the coolest

• temperature; left is the coolest and the right is the hottest

• luminosity ( brightness)

• size of the star

Multiple Choice

What information is found on the y-axis of the HR diagram?

• temperature; the left is the hottest and the right is the coolest

• size of the star

• color of the star

• luminosity of the star.

Multiple Choice

Which classification of stars form a diagonal line on the Hertzsprung-Russell diagram, with surface temperatures increasing as brightness increases?

• super giants

• giants

• main sequence stars

• white dwarfs

Multiple Choice

The Hertzsprung-Russell diagram shows how the sun is classified among the stars. A star that is several thousand times brighter than the sun with a temperature lower than 4,000 K would be classified as —

• a main-sequence star in spectral class B

• a supergiant in spectral class K

• a main-sequence star in spectral class K or M

• a white dwarf in spectral class B

Multiple Choice

Which color is a very hot main sequence star most likely to have?

• orange

• blue

• yellow

• red

​PROPER POSITIONS PLEASE!!

​EXIT TICKET TIME!!

MAKE SURE YOU HAVE YOUR VOCABULARY CARDS TOO!!!

Multiple Choice

what is the H-R Diagram?

• used to classify stars by their luminosity, temperature, and spectral class.

• used to classify stars by their luminosity.

• used to classify stars by their spectral class.

• used to classify stars by their temperature,

Multiple Choice

WHERE WOULD THE MAIN SEQUENCE STARS BE LOCATED?

• area z

• area p

• area m

• area x

Multiple Choice

what information is found on the x-axis of the HR Diagram?

• temperature; left is hottest and the right is the coolest

• temperature; left is the coolest and the right is the hottest

• luminosity ( brightness)

• size of the star

Multiple Choice

What is a main sequence star?

•  a series of star types to which most stars belong, represented on the H-R diagram as a continuous band extending from the upper left (hot, bright stars) to the lower right (cool, dim stars).

•  a series of star types to which most stars belong, represented on the H-R diagram.

•  a series of star types to which most stars belong, represented on the H-R diagram as a continuous band extending from the bottom left (hot, bright stars) to the upper right (cool, dim stars).

Multiple Choice

Most stars in the universe fit into one of the four areas on this Hertzsprung-Russell diagram. Which area of the diagram represents the white dwarfs?

• area M

• area X

• area P

• area Z

Multiple Choice

What is a super giant?

• a very large star that is even brighter than a giant, but is relatively cool.

• a medium star that is even brighter than a giant, but is relatively cool.

• a very small star that is even brighter than a giant, but is relatively cool.

Multiple Choice

What information is found on the y-axis of the HR diagram?

• temperature; the left is the hottest and the right is the coolest

• size of the star

• color of the star

• luminosity of the star.

Multiple Choice

where would red supergiants be located

• area m

• area x

• area p

• area z

Multiple Choice

What is a white dwarf?

• small, dense, and hot whitish star of low luminosity

• medium, dense, and hot whitish star of low luminosity

• large, dense, and hot whitish star of low luminosity

Multiple Choice

where would red giants be located?

• area z

• area x

• area p

• area m

Multiple Choice

What is a giant?

• a star that is larger in size and luminosity than main sequence stars.

• a star that is small in size and luminosity than main sequence stars.

• a star that is medium in size and luminosity than main sequence stars.

Multiple Choice

Two stars are identified on the Hertzsprung-Russell diagram below. Based on this diagram, how do the characteristics of Star 1 and Star 2 compare?

• Star 1 is cooler and less bright than Star 2.

• Star 1 is hotter and brighter than Star 2.

• Star 1 is cooler and brighter than Star 2.

• Star 1 is hotter and less bright than Star 2.

Multiple Choice

Which classification of stars form a diagonal line on the Hertzsprung-Russell diagram, with surface temperatures increasing as brightness increases?

• super giants

• giants

• main sequence stars

• white dwarfs

Multiple Choice

Which color is a very hot main sequence star most likely to have?

• orange

• blue

• yellow

• red