1of3 LAB Constructing an HR Diagram date ______Last Name ______, First ______per___

Construct an HR diagram using the data table provided by your teacher. An HR diagram is a graph of star temperature vs. star brightness. The column labeled M(V) contains absolute brightness data. Remember absolute brightness is a reverse scale, the lower the number the brighter the star. Absolute brightness is defined as the brightness of a star as if you saw it from a distance of 10 (about 32 light-). Procedure: 1. Lets set up the graph. Absolute brightness will be on the Y axis and temperature(K) will be on the X axis. a. Label both axis on your graph. Leave room for numbering. b. Let each square on the X axis equal 2000ºK. Number the X axis in reverse from 50,000º to 0º. Do not number every line, instead, number every 5 lines. c. Let each square on the Y axis equal 1 magnitude. Number the Y axis from –10 to +15. Zero(0), should be on the 10th line up from the bottom. Do not number every line, instead number every 5 lines. d. Give your graph a title “Temperature Vs. Absolute Brightness” 2. Now your ready to plot the . Start by plotting the stars. Mark a point for each star

Title______

LAB Construct an HR Diagram 2of3 Analysis and Conclusions:

1. Does your graph and the original graph created by Hertzsprung and Russell have similar patterns? Describe the patterns.

2. Name 3 stars from your graph.

3. Name 1 Giant or Super Giant

4. Name 1

5. Name one

6. Which star will have the overall shortest life?

7. Which star will have the overall longest life?

LAB Construct an HR Diagram 3of3

Star M(V Temp Type Star M(V) Temp Type

Sun 4.8 5840 G2 Sirius A 1.4 9620 A1 Canopus -3.1 7400 F0 Arcturus -0.4 4590 K2 Alpha *Alpha Centauri A 4.3 5840 G2 Centauri B 5.8 4900 K1 Capella -0.6 5150 G8 Rigel -7.2 12140 B8 Procyon A 2.6 6580 F5 Betelgeuse -5.7 3200 M2 Achemar -2.4 20500 B3 Hadar -5.3 25500 B1 Altair 2.2 8060 A7 Aldebaran -0.8 4130 K5 Spica -3.4 25500 B1 Antares -5.2 3340 M1 Fomalhaut 2.0 9060 A3 Pollux 1.0 4900 K0 Deneb -7.2 9340 A2 Vega 0.5 9900 A0 -0.8 13260 B7 Acrux -4.0 28000 B0 Adhara -5.2 23000 B2 Shaula -3.4 25500 B1 Bellatrix -4.3 23000 B2 Castor 1.2 9620 A1 Gacrux -0.5 3750 M3 Beta Centauri -5.1 25500 B1 Barnard's 13.2 2800 M4 Al Na'ir -1.1 15550 B5 Miaplacidu -0.6 9300 A0 Elnath -1.6 12400 B7 Alnilam -6.2 26950 B0 Mirfak -4.6 7700 F5 Alnitak -5.9 33600 O9 Dubhe 0.2 4900 K0 Alioth 0.4 9900 A0 Peacock -2.3 20500 B3 Kaus Australis -0.3 11000 B9 Theta Scorpii -5.6 7400 F0 Atria -0.1 4590 K2 Alkaid -1.7 20500 B3 Avior -2.1 4900 K0 Delta Canis -8.0 6100 F8 Alhena 0.0 9900 A0 Majoris Menkalinan 0.6 9340 A2 Polaris -4.6 6100 F8 Altair 2.2 8060 A7 AD Leonis 11.0 2940 M3 *Sirius B 11.2 14800 DA *Sirius A 1.4 9620 A1 G51-I5 17.0 2500 M7 Ross 154 13.1 2800 M4 *Proxima Van Maanen's Centauri 15.5 2670 M5.5 Star 14.2 13000 DB 16.7 2670 M6 *UV Ceti (B) 16.0 2670 M6 Altair 2.2 8060 A7 AD Leonis 11.0 2940 M3 Epsilon 7.0 4130 K3 *61 Cygni A 7.6 4130 K3

LAB Construct an HR Diagram