Experiment 13.2 Plotting the Hertzsprung-Russell Diagram for Well
Known Stars.
AIM: To become familiar with the Hertzsprung-Russell diagram and to classify a
number of stars that we see in our sky.
METHOD ONE: Use the information in the table below to plot the well known stars
in our galaxy onto a Hertzsprung-Russell diagram. Use graph paper but use the axes
shown.
1 000 000
Luminosity compared to Sun
100 000
10 000
1 000
100
10
1
0.1
0.01
0.001
0.0001
0.000 1
40 000
20000
10000
5000
2500
Surface Temperature (K)
Name
Surface Temperature
(K)
The Sun
Proxima Centauri
Alpha Centauri A
Alpha Centauri B
Sirius A
Sirius B
Canopus
Betelgeuse
Rigel
Beta Centauri
Wolf 359
Barnard’s Star
Arcturus
Procyon
Archenar
Aldebaran
5860
3240
5860
5250
9230
9000
7700
3450
11200
24000
2640
3240
4420
6440
15400
15400
Luminosity
Compared to
Sun
1
0.00006
1.6
0.45
23.5
0.003
1400
12600
42000
3500
0.000 02
0.000 45
110
7.2
200
95
RESULTS:
Complete the Hertzsprung-Russell diagram, labelling all axes clearly.
Classify each of the stars as Red Giants, White Dwarfs, Main Sequence etc.
CONCLUSION: Answer the following questions
1 Which star is the most luminous star?
2 Which star has the lowest surface temperature?
3 Which star has the highest surface temperature?
4 Why isn’t this star the most luminous?
METHOD TWO Hertzsprung-Russell diagrams are easily drawn using a spreadsheet
package. Draw an XY scatter graph but remember to do the following
 Set the scale of the X axis as a log scale
 Make sure the X axis range is from 1000 to 100 000
 Reverse the order of the X axis range
 Set the Y axis scale to a log scale.