An HR plot is given with many stars already plotted on page 17. Use the Luminosities and Temperatures given for each of
Posted: Thu Jul 07, 2022 12:03 pm
An HR plot is given with many stars already plotted on page 17. Use the Luminosities and
Temperatures given for each of the following stars to plot and label them on the HR diagram
The Hertzsprung - Russell Diagram Introduction The Hertzsprung-Russell (HR) diagram is a graphical method of displaying properties of a large number of stars. The absolute luminosity of stars is plotted on the vertical scale of the graph with the Sun's luminosity used as a standard of one. All other stars are plotted as multiples or fractions of the Sun's luminosity. It can be seen that stars range in luminosity from 1/10,000 (0001) to 100,000 thousand times the luminosity of the Sun. A star's surface temperature is plotted on the horizontal scale. The HR diagram uses the lower right as the origin of the axes with luminosity increasing up and surface temperature increasing to the left. By plotting thousands of stars astronomers have discovered that they fall into three areas of the HR diagram: main sequence, giants, and white dwarfs. This also reveals more about the nature of each star. Procedure 1. An HR plot is given with many stars already plotted on page 17. Use the Luminosities and Temperatures given for each of the following stars to plot and label them on the HR diagram a. Sirius B Luminosity: 0.005/ Temp:-22,000 K b. Barnard's Star Luminosity: 0.004/ Temp:-3300 K c. Spica A Luminosity: 4000/ Temp:-22,000 K d. Sun Luminositv: 3/ Temp: 5500K e. Antares Luminositv: 12.000/ Temp:-4.000 K 2. Neatly label the following areas on the your HR plot: a. Main sequence b. Giants (including supergiants) c. White dwarfs 3. The following is a list of stars with their surface temperature and luminosity given. Use your HR diagram to identify the type of star (main sequence, giant, or white dwarf). Temperature Luminosity Type 30,000 12,000 12,000 4000 4000 5000 0.001 20 0.01 3000 15
4. Suppose you have identified two main sequence stars, A and B. "A" has a surface temperature of 30,000 Kelvins while 'B' has a surface temperature of 3000 Kelvins. a. Since they are both main sequence stars, why is A so much hotter than B? In other words, what is the difference between main sequence stars near the top of the plot versus those near the bottom? b. Which one will have a longer life as a main sequence star and why? 5. Giant stars have relatively low surface temperatures but very high luminosities. Explain how astronomers use this information to conclude that these stars are, in fact, very large. 6. Using the text, summarize the life cycle of a star like the sun from birth to death using the stages on the HR diagram. 7. Briefly, how does the death of a massive star differ from the death of a sun-like star? 16
Tip: to fill out this lab use text box, and Microsoft word shapes, if you have the most updated vsn there is a draw feature, just save it as a pdf for me to see it. 100,000 10,000 Absolute luminosity (Sun-1) 1000 100 10 0.1 0.01 0.001 0.0001 882 889 80 Surface temperature (in thousands of degrees Kelvin) 6 4 N
Temperatures given for each of the following stars to plot and label them on the HR diagram
The Hertzsprung - Russell Diagram Introduction The Hertzsprung-Russell (HR) diagram is a graphical method of displaying properties of a large number of stars. The absolute luminosity of stars is plotted on the vertical scale of the graph with the Sun's luminosity used as a standard of one. All other stars are plotted as multiples or fractions of the Sun's luminosity. It can be seen that stars range in luminosity from 1/10,000 (0001) to 100,000 thousand times the luminosity of the Sun. A star's surface temperature is plotted on the horizontal scale. The HR diagram uses the lower right as the origin of the axes with luminosity increasing up and surface temperature increasing to the left. By plotting thousands of stars astronomers have discovered that they fall into three areas of the HR diagram: main sequence, giants, and white dwarfs. This also reveals more about the nature of each star. Procedure 1. An HR plot is given with many stars already plotted on page 17. Use the Luminosities and Temperatures given for each of the following stars to plot and label them on the HR diagram a. Sirius B Luminosity: 0.005/ Temp:-22,000 K b. Barnard's Star Luminosity: 0.004/ Temp:-3300 K c. Spica A Luminosity: 4000/ Temp:-22,000 K d. Sun Luminositv: 3/ Temp: 5500K e. Antares Luminositv: 12.000/ Temp:-4.000 K 2. Neatly label the following areas on the your HR plot: a. Main sequence b. Giants (including supergiants) c. White dwarfs 3. The following is a list of stars with their surface temperature and luminosity given. Use your HR diagram to identify the type of star (main sequence, giant, or white dwarf). Temperature Luminosity Type 30,000 12,000 12,000 4000 4000 5000 0.001 20 0.01 3000 15
4. Suppose you have identified two main sequence stars, A and B. "A" has a surface temperature of 30,000 Kelvins while 'B' has a surface temperature of 3000 Kelvins. a. Since they are both main sequence stars, why is A so much hotter than B? In other words, what is the difference between main sequence stars near the top of the plot versus those near the bottom? b. Which one will have a longer life as a main sequence star and why? 5. Giant stars have relatively low surface temperatures but very high luminosities. Explain how astronomers use this information to conclude that these stars are, in fact, very large. 6. Using the text, summarize the life cycle of a star like the sun from birth to death using the stages on the HR diagram. 7. Briefly, how does the death of a massive star differ from the death of a sun-like star? 16
Tip: to fill out this lab use text box, and Microsoft word shapes, if you have the most updated vsn there is a draw feature, just save it as a pdf for me to see it. 100,000 10,000 Absolute luminosity (Sun-1) 1000 100 10 0.1 0.01 0.001 0.0001 882 889 80 Surface temperature (in thousands of degrees Kelvin) 6 4 N